Zinc metal batteries (ZnBs) are poised as the next-generation energy storage solution, complementing lithium-ion batteries, thanks to their cost-effectiveness and safety advantages. These benefits originate from the abundance of zinc and its compatibility with non-flammable aqueous electrolytes. However, the inherent instability of zinc in aqueous environments, manifested through hydrogen evolution reactions (HER) and dendritic growth, has hindered commercialization due to poor cycling stability. Enter potassium polyacrylate (PAAK)-based water-in-polymer salt electrolyte (WiPSE), a novel variant of water-in-salt electrolytes (WiSE), designed to mitigate side reactions associated with water redox processes, thereby enhancing the cyclic stability of ZnBs. In this study, WiPSE was employed in ZnBs featuring lignin and carbon composites as cathode materials. Our research highlights the crucial function of acrylate groups from WiPSE in stabilizing the ionic flux on the surface of the Zn electrode. This stabilization promotes the parallel deposition of Zn along the (002) plane, resulting in a significant reduction in dendritic growth. Notably, our sustainable Zn-lignin battery showcases remarkable cyclic stability, retaining 80% of its initial capacity after 8000 cycles at a high current rate (1 A g^-1) and maintaining over 75% capacity retention up to 2000 cycles at a low current rate (0.2 A g^-1). This study showcases the practical application of WiPSE for the development of low-cost, dendrite-free, and scalable ZnBs.

Supercapacitors are efficient and versatile energy storage devices, offering remarkable power density, fast charge/discharge rates, and exceptional cycle life. As research continues to push the boundaries of their performance, electrode fabrication techniques are critical aspects influencing the overall capabilities of supercapacitors. Herein, we aim to shed light on the advantages offered by dry electrode processing for advanced supercapacitors. Notably, our study explores the performance of these electrodes in three different types of electrolytes: organic, ionic liquids, and quasi-solid states. By examining the impact of dry electrode processing on various electrode and electrolyte systems, we show valuable insights into the versatility and efficacy of this technique. The supercapacitors employing dry electrodes demonstrated significant improvements compared with conventional wet electrodes, with a lifespan extension of +45% in organic, +192% in ionic liquids, and +84% in quasi-solid electrolytes. Moreover, the increased electrode densities achievable through the dry approach directly translate to improved volumetric outputs, enhancing energy storage capacities within compact form factors. Notably, dry electrode-prepared supercapacitors outperformed their wet electrode counterparts, exhibiting a higher energy density of 6.1 Wh cm^-3 compared with 4.7 Wh cm^-3 at a high power density of 195 W cm^-3, marking a substantial 28% energy improvement in the quasi-solid electrolyte.

Arising from the increasing demand for electric vehicles (EVs), Ni-rich LiNi_xCo_yMn_zO₂ (NCM, x + y + z = 1, x ≥ 0.8) cathode with greatly increased energy density are being researched and commercialized for lithium-ion batteries (LIBs). However, parasitic crack formation during the discharge–charge cycling process remains as a major degradation mechanism. Cracking leads to increase in the specific surface area, loss of electrical contact between the primary particles, and facilitates liquid electrolyte infiltration into the cathode active material, accelerating capacity fading and decrease in lifetime. In contrast, Ni-rich NCM when used as a single crystal exhibits superior cycling performances due to its rigid mechanical property that resists cracking during long charge–discharge process even under harsh conditions. In this paper, we present comparative investigation between single crystal Ni-rich LiNi_0.92Co_0.04Mn_0.04O₂ (SC) and polycrystalline Ni-rich LiNi_0.92Co_0.04Mn_0.04O₂ (PC). The relatively improved cycling performances of SC are attributed to smaller anisotropic volume change, higher reversibility of phase transition, and resistance to crack formation. The superior properties of SC are demonstrated by in situ characterization and battery tests. Consequently, it is inferred from the results obtained that optimization of preparation conditions can be regarded as a key approach to obtain well crystallized and superior electrochemical performances.

Organic electrode materials (OEMs) constitute an attractive class of energy storage materials for potassium-ion batteries, but their application is severely hindered by sluggish kinetics and limited capacities. Herein, inorganic molecules covalent combination strategy is proposed to drive advanced potassium organic batteries. Specifically, molecular selenium, possessing high potential of conductivity and electroactivity, is covalently bonded with organic matrix, that is symmetrical selenophene-annulated dipolyperylene diimide (PDI2-2Se), is designed to verify the feasibility. The inorganic-anchored OEM (PDI2-2Se) can be electrochemically activated to form organic (PDI2 matrix)–inorganic (Se) hybrids during initial cycles. State-of-the-art 3D tomography reveals that a “mutual-accelerating” effect was realized, that is, the 10-nm Se quantum dots, possessing high conductivity, facilitate charge transfer in organics as well store K⁺-ions, and organic PDI2 matrix benefits the encapsulation of Se, thereby suppressing shuttle effect and volume fluctuation during cycling, endowing resulting PDI2/Se hybrids with both high-rate capacities and longevity. The concept of inorganic-configurated OEM through covalent bonds, in principle, can also be extended to design novel functional organic-redox electrodes for other high-performance secondary batteries.

Eco-friendly and antimicrobial globular protein lysozyme is widely produced for several commercial applications. Interestingly, it can also be able to convert mechanical and thermal energy into electricity due to its piezo- and pyroelectric nature. Here, we demonstrate engineering of lysozyme into piezoelectric devices that can exploit the potential of lysozyme as environmentally friendly, biocompatible material for mechanical energy harvesting and sensorics, especially in micropowered electronic applications. Noteworthy that this flexible, shape adaptive devices made of crystalline lysozyme obtained from hen egg white exhibited a longitudinal piezoelectric charge coefficient (d ∼ 2.7 pC N^-1) and piezoelectric voltage coefficient (g ∼ 76.24 mV m N^-1) which are comparable to those of quartz (∼2.3 pC N^-1 and 50 mV m N^-1). Simple finger tapping on bio-organic energy harvester (BEH) made of lysozyme produced up to 350 mV peak-to-peak voltage, and a maximum instantaneous power output of 2.2 nW cm^-2. We also demonstrated that the BEH could be used for self-powered motion sensing for real-time monitoring of different body functions. These results pave the way toward self-powered, autonomous, environmental-friendly bio-organic devices for flexible energy harvesting, storage, and in wearable healthcare monitoring.

Few-layer nanosheets (NSs) of hexagonal boron nitride (h-BN) and molybdenum disulfide (MoS₂) display notable piezoelectric properties. Yet, their integration into polymers typically yields non-piezoelectric composites due to NSs’ random distribution. We introduce a facile method for fabricating intrinsic piezoelectric composites incorporated with NSs without electric poling. Our innovative process aligns NSs within polyvinyl alcohol polymer, leveraging ice-water interfacial tension, water crystallization thrust, and directional cross-linking during freezing. The resulting PE composites exhibit a maximum piezoelectric coefficient of up to 25.5–28.4 pC N^-1, comparable to polyvinylidene difluoride (PVDF), with significant cost-efficiency, safety, and scalability advantages over conventional materials. Using this composite, we develop highly sensitive wearable pressure and strain sensors, and an ultrasound energy harvester. These sensors detect finger bending and differentiate between walking and running, while the harvester generates ∼1.18 V/2.31 µA under 1 W cm^-2 ultrasound input underwater. This universal method offers a novel manufacturing technique for piezoelectric composites, demonstrating remarkable effectiveness in synthesizing intrinsic piezoelectric composites based on 2D materials. Moreover, its potential extends to applications in wearable electronics and energy harvesting, promising significant advancements in these fields.

Sodium-ion-based electrochromic device (SECD) has been identified as an appealing cost-effective alternative of lithium-based counterparts, only if it can address the challenges in association with the inadequate electrochromic performance. In this regard, the quantized strategy is a particularly promising approach owing to the large surface-to-volume ratio and high reaction activity. However, quantum dots inevitably suffer from volume changes and undesired aggregation during electrochemical cycling. Herein, bioinspired from the robust connection of alveoli in lung, we propose a stable electrode, where WO₃ quantum dots (WQDs) are robustly anchored on Ti₃C₂ MXene through the strong chemical bonds of W-O-Ti. Theoretical results reveal the fundamental mechanism of the volume changes within WQDs and the dynamic diffusion process of sodium ions. The WQD@MXene electrodes exhibit a nearly twofold enhancement in cycling performance (1000 vs 500 cycles), coloration speed (3.2 vs 6.0 s), and areal capacity (87.5 vs 43.9 mAh m^-2 at 0.1 mA cm^-2), compared to those of the pristine WQD electrode. As a proof-of-concept demonstration, a smart house system integrated with SECDs demonstrates a “3-in-1” device, enabling a combination of energy-saving, energy storage, and display functionalities. The present work significantly advances the versatile applications of cost-effective electrochromic electronics in interdisciplinary.

Tin perovskites are emerging as promising alternatives to their lead-based counterparts for high-performance and flexible perovskite solar cells. However, their rapid crystallization often leads to inadequate film quality and poor device performance. In this study, the role of GeI₂ as an additive is investigated for controlling the nucleation and crystallization processes of formamidinium tin triiodide (FASnI₃). The findings reveal the preferential formation of a Ge-rich layer at the bottom of the perovskite film upon the introduction of GeI₂. It is proposed that the initial formation of the Ge complex acts as a crystallization regulator, promoting oriented growth of subsequent FASnI₃ crystals and enhancing overall crystallinity. Through the incorporation of an optimal amount of GeI₂, flexible Sn perovskite solar cells with an efficiency of 10.8% were achieved. Furthermore, it was observed that the GeI₂ additive ensures a remarkable shelf-life for the devices, with the rigid cells retaining 91% of their initial performance after more than 13 800 h of storage in an N₂ gas environment. This study elucidates the mechanistic role of GeI₂ in regulating the nucleation and crystallization process of tin perovskites, providing valuable insights into the significance of additive engineering for the development of high-performance flexible tin perovskite solar cells.

The all-vanadium redox flow battery (VRFB) plays an important role in the energy transition toward renewable technologies by providing grid-scale energy storage. Their deployment, however, is limited by the lack of membranes that provide both a high energy efficiency and capacity retention. Typically, the improvement of the battery’s energy efficiency comes at the cost of its capacity retention. Herein, novel N-alkylated and N-benzylated meta-polybenzimidazole (m-PBI) membranes are used to understand the molecular requirements of the polymer electrolyte in a vanadium redox flow battery, providing an important toolbox for future research toward next-generation membrane materials in energy storage devices. The addition of an ethyl side chain to the m-PBI backbone increases its affinity toward the acidic electrolyte, thereby increasing its ionic conductivity and the corresponding energy efficiency of the VRFB cell from 70% to 78% at a current density of 200 mA cm^-2. In addition, cells equipped with ethylated m-PBI showed better capacity retention than their pristine counterpart, respectively 91% versus 87%, over 200 cycles at 200 mA cm^-2. The outstanding VRFB cycling performance, together with the low-cost and fluorine-free chemistry of the N-alkylated m-PBI polymer, makes this material a promising membrane to be used in next-generation VRFB systems.

Nowadays, a stack of heavily doped polysilicon (poly-Si) and tunnel oxide (SiO_x) is widely employed to improve the passivation performance in n-type tunnel oxide passivated contact (TOPCon) silicon solar cells. In this case, it is critical to develop an in-line advanced fabrication process capable of producing high-quality tunnel SiO_x. Herein, an in-line ozone-gas oxidation (OGO) process to prepare the tunnel SiO_x is proposed to be applied in n-type TOPCon solar cell fabrication, which has obtained better performance compared with previously reported in-line plasma-assisted N₂O oxidation (PANO) process. In order to explore the underlying mechanism, the electrical properties of the OGO and PANO tunnel SiO_x are analyzed by deep-level transient spectroscopy technology. Notably, continuous interface states in the band gap are detected for OGO tunnel SiO_x, with the interface state densities (D_it) of 1.2 × 10¹²–3.6 × 10¹² cm^-2 eV^-1 distributed in E_v + (0.15–0.40) eV, which is significantly lower than PANO tunnel SiO_x. Furthermore, X-ray photoelectron spectroscopy analysis indicate that the percentage of SiO₂ (Si⁴⁺) in OGO tunnel SiO_x is higher than which in PANO tunnel SiO_x. Therefore, we ascribe the lower D_it to the good inhibitory effects on the formation of low-valent silicon oxides during the OGO process. In a nutshell, OGO tunnel SiO_x has a great potential to be applied in n-type TOPCon silicon solar cell, which may be available for global photovoltaics industry.

Attempts to remove environmentally harmful materials in mass production industries are always a major issue and draw attention if the substitution guarantees a chance to lower fabrication cost and to improve device performance, as in a wide bandgap Zn_1-xMg_xO (ZMO) to replace the CdS buffer in Cu(In_1-x,Ga_x)Se₂ (CIGSe) thin-film solar cell structure. ZMO is one of the candidates for the buffer material in CIGSe thin-film solar cells with a wide and controllable bandgap depending on the Mg content, which can be helpful in attaining a suitable conduction band offset. Hence, compared to the fixed and limited bandgap of a CdS buffer, a ZMO buffer may provide advantages in V_oc and J_sc based on its controllable and wide bandgap, even with a relatively wider bandgap CIGSe thin-film solar cell. In addition, to solve problems with the defect sites at the ZMO/CIGSe junction interface, a few-nanometer ZnS layer is employed for heterojunction interface passivation, forming a ZMO/ZnS buffer structure by atomic layer deposition (ALD). Finally, a Cd-free all-dry-processed CIGSe solar cell with a wider bandgap (1.25 eV) and ALD-grown buffer structure exhibited the best power conversion efficiency of 19.1%, which exhibited a higher performance than the CdS counterpart.

The development of an analytical method for determining the properties of quantum dots (QDs) is crucial for improving the optical performance of QD-based displays. Therefore, synchrotron-based X-ray photoelectron spectroscopy (XPS) is designed here to accurately characterize the chemical and structural differences between different QDs. This method enables the determination of the reason for the minimal differences between the optical properties of different QDs depending on the synthesis process, which is difficult to determine using conventional methods alone. Combined with model simulations, the XPS spectra obtained at different photon energies reveal the internal structures and chemical-state distributions of the QDs. In particular, the QD synthesized under optimal conditions demonstrates a relatively lower degree of oxidation of the core and more uniformly stacked ZnSe/ZnS shell layers. The internal structures and chemical-state distributions of QDs are closely related to their optical properties. Finally, the synchrotron-based XPS proposed here can be applied to compare nearly equivalent QDs with slightly different optical properties.

Decoupling electrical and thermal properties to enhance the figure of merit of thermoelectric materials underscores an in-depth understanding of the mechanisms that govern the transfer of charge carriers. Typically, a factor that contributes to the optimization of thermal conductivity is often found to be detrimental to the electrical transport properties. Here, we systematically investigated 26 dimeric MX₂-type compounds (where M represents a metal and X represents a nonmetal element) to explore the influence of the electronic configurations of metal cations on lattice thermal transport and thermoelectric performance using first-principles calculations. A principled scheme has been identified that the filled outer orbitals of the cation lead to a significantly lower lattice thermal conductivity compared to that of the partly occupied case for MX₂, due to the much weakened bonds manifested by the shallow potential well, smaller interatomic force constants, and higher atomic displacement parameters. Based on these findings, we propose two ionic compounds, BaAs and BaSe₂, to realize reasonable high electrical conductivities through the structural anisotropy caused by the inserted covalent X₂ dimers while still maintaining the large lattice anharmonicity. The combined superior electrical and thermal properties of BaSe₂ lead to a high n-type thermoelectric ZT value of 2.3 at 500 K. This work clarifies the structural origin of the heat transport properties of dimeric MX₂-type compounds and provides an insightful strategy for developing promising thermoelectric materials.

The exploration of heterostructures composed of two-dimensional (2D) transition metal dichalcogenide (TMDc) materials has garnered significant research attention due to the distinctive properties of each individual component and their phase-dependent unique properties. Using the plasma-enhanced chemical vapor deposition (PECVD) method, we analyze the fabrication of heterostructures consisting of two phases of molybdenum disulfide (MoS₂) in four different cases. The initial hydrogen evolution reaction (HER) polarization curve indicates that the activity of the heterostructure MoS₂ is consistent with that of the underlying MoS₂, rather than the surface activity of the upper MoS₂. This behavior can be attributed to the presence of Schottky barriers, which include contact resistance, which significantly hampers the efficient charge transfer at junctions between the two different phases of MoS₂ layers and is mediated by van der Waals bonds. Remarkably, the energy barrier at the junction dissipates upon reaching a certain electrochemical potential, indicating surface activation from the top phase of MoS₂ in the heterostructure. Notably, the 1T/2H MoS₂ heterostructure demonstrates enhanced electrochemical stability compared to its metastable 1T-MoS₂. This fundamental understanding paves the way for the creation of phase-controllable heterostructures through an experimentally viable PECVD, offering significant promise for a wide range of applications.

The increasing importance of high-purity isopropyl alcohol (IPA) in semiconductor processing technology has led to a higher demand for technologies capable of detecting impurities in IPA. Although accurate and various impurity detection technologies have been developed, most of them have limitations in real-time and repeatable detection of impurities. Herein, for the first time, surface plasmon resonance (SPR) sensor was developed utilizing graphene transferred Au film (Au/graphene) to detect sub-ppm levels of 2,4-dinitrophenol (2,4-DNP) dissolved in IPA and this sensor demonstrates the ability to detect 2,4-DNP in real-time with great reversibility. The adsorption of 2,4-DNP to graphene is found to be stronger than that for Au film because of noncovalent graphene π–π stacking interaction, and the effect of graphene is demonstrated through density function theory (DFT) calculations and enhancement in sensing performance of Au/graphene sensor. Additionally, the presence of noncovalent π–π stacking interaction between 2,4-DNP and graphene has been demonstrated by confirming the p-doping effect of graphene-based solution field-effect transistor measurements and consecutive Raman spectra analysis. This study offers experimental and theoretical insights into the adsorption kinetics of 2,4-DNP dissolved in IPA and provides promising perspectives for real-time sensing technology utilizing label-free graphene to detect impurities in high-purity cleaning agents.

This study introduces a cut-to-fit methodology for customizing bulk aramid aerogels into form factors suitable for wearable energy storage. Owing to strong intercomponent bonds within aramid-based building blocks, it is possible to delaminate layered bulk aerogel into flexible and thinner sheets, enabling efficient mass production. This process allows for precise customization of aerogel dimensions, shape, and elasticity, ensuring high resilience to deformation along with excellent thermal and impact resistance. Incorporation of conductive carbon nanotubes on the surface significantly enhances electrical conductivity and multi-catalytic activity while retaining the inherent advantages of aramids. These advancements facilitate the use of flexible and conductive electrodes as air cathodes in solid-state zinc–air batteries (ZABs), which demonstrate superior cyclic performance and lifecycles exceeding 160 h. Furthermore, aramid-based packaging provides superior protection for pouch-type ZABs, ensuring a consistent power supply even in severe conditions. These batteries are capable of withstanding structural deformations and absorbing physical and thermal shocks, such as impacts and exposure to fire. Moreover, the innovative reassembly of custom-cut single-pouch cells into battery modules allows for enhanced power output, tailored to wearable applications. This highlights the potential of the technology for a wide array of wearable devices requiring dependable energy sources in demanding environments.

Homogeneous films with tailored microporous structures are crucial for several applications; however, fabricating such films presents significant challenges. This is primarily because most microporous materials have crystal sizes in the nano- and micrometer ranges, which inevitably generates intergranular spaces in the films, thereby complicating the fabrication of these thin films. In this study, functionalized metal-organic polyhedra (MOPs) are used as discrete microporous units and assembled into homogenous microporous films. The generation of intergranular spaces is avoided while controlling packing parameters and film thicknesses. Initially, the MOP units, influenced by van der Waals forces between carbon chains of functionalized adipic acids, display an affinity to form spindle-shaped blocks and islands. As the MOP concentration increases, these structures self-assembled into a hexagonally packed structure with an in-plane orientation and a maximum stacking of two layers of MOPs. By contrast, un-functionalized MOPs form a disordered film structure owing to random agglomeration. Evidently, functionalized adipic acid influences the orientation of the MOP network films with uniformly distributed micropores, effectively preventing the formation of intergranular spaces. Additionally, formaldehyde adsorption and desorption experiments revealed that the MOP network films possess superior adsorption and desorption capacities. The proposed approach signifies a breakthrough in the fabrication of homogenous microporous films.

Various novel conjugated polymers (CPs) have been developed for organic photodetectors (OPDs), but their application to practical image sensors such as X-ray, R/G/B, and fingerprint sensors is rare. In this article, we report the entire process from the synthesis and molecular engineering of novel CPs to the development of OPDs and fingerprint image sensors. We synthesized six benzo[1,2-d:4,5-d’]bis(oxazole) (BBO)-based CPs by modifying the alkyl side chains of the CPs. Several relationships between the molecular structure and the OPD performance were revealed, and increasing the number of linear octyl side chains on the conjugated backbone was the best way to improve J_ph and reduce J_d in the OPDs. The optimized CP demonstrated promising OPD performance with a responsivity (R) of 0.22 A/W, specific detectivity (D*) of 1.05 × 10¹³ Jones at a bias of -1 V, rising/falling response time of 2.9/6.9 µs, and cut-off frequency (f_-3dB) of 134 kHz under collimated 530 nm LED irradiation. Finally, a fingerprint image sensor was fabricated by stacking the POTB1-based OPD layer on the organic thin-film transistors (318 ppi). The image contrast caused by the valleys and ridges in the fingerprints was obtained as a digital signal.

The conversion of sound vibration into electrical potential is a critical function performed by cochlear hair cells. Unlike the regenerative capacity found in various other cells throughout the body, cochlear sensory cells lack the ability to regenerate once damaged. Furthermore, a decline in the quantity of these cells results in a deterioration of auditory function. Piezoelectric materials can generate electric charge in response to sound wave vibration, making them theoretically suitable for replacing hair cell function. This study explores an innovative approach using piezoelectric nanocomposite filaments, namely poly(vinylidene fluoride), poly(vinylidene fluoride)/barium titanate, and poly(vinylidene fluoride)/reduced graphene oxide, as self-powered acoustic sensors designed to function in place of cochlear hair cells. These flexible filaments demonstrate a unique ability to generate electricity in response to frequency sounds from 50 up to 1000 Hz at moderate sound pressure levels (60–95 dB), approaching the audible range with an overall acoustoelectric energy conversion efficiency of 3.25%. Serving as self-powered acoustic sensors, these flexible filaments hold promise for potential applications in cochlear implants, with a high sensitivity of 117.5 mV (Pa·cm²)^-1. The cytocompatibility of these filaments was assessed through in vitro viability tests conducted on three cell lines, serving as a model for inner ear cells.

The rapid development of nanotechnology has significantly revolutionized wearable electronics and expanded their functionality. Through introducing innovative solutions for energy harvesting and autonomous sensing, this research presents a cost-effective strategy to enhance the performance of triboelectric nanogenerators (TENGs). The TENG was fabricated from polyvinylidene fluoride (PVDF) and N, N’-poly(methyl methacrylate) (PMMA) blend with a porous structure via a novel optimized quenching method. The developed approach results in a high β-phase content (85.7%) PVDF/3wt.%PMMA porous blend, known for its superior piezoelectric properties. PVDF/3wt.%PMMA modified porous TENG demonstrates remarkable electrical output, with a dielectric constant of 40 and an open-circuit voltage of approximately 600 V. The porous matrix notably increases durability, enduring over 36 000 operational cycles without performance degradation. Moreover, practical applications were explored in this research, including powering LEDs and pacemakers with a maximum power output of 750 mW m^-2. Also, TENG served as a self-powered tactile sensor for robotic applications in various temperature conditions. The work highlights the potential of the PVDF/PMMA porous blend to utilize the next-generation self-powered sensors and power small electronic devices.

This study first demonstrates the potential of organic photoabsorbing blends in overcoming a critical limitation of metal oxide photoanodes in tandem modules: insufficient photogenerated current. Various organic blends, including PTB7-Th:FOIC, PTB7-Th:O6T-4F, PM6:Y6, and PM6:FM, were systematically tested. When coupled with electron transport layer (ETL) contacts, these blends exhibit exceptional charge separation and extraction, with PM6:Y6 achieving saturation photocurrents up to 16.8 mA cm^-2 at 1.23 V_RHE (oxygen evolution thermodynamic potential). For the first time, a tandem structure utilizing organic photoanodes has been computationally designed and fabricated and the implementation of a double PM6:Y6 photoanode/photovoltaic structure resulted in photogenerated currents exceeding 7 mA cm^-2 at 0 V_RHE (hydrogen evolution thermodynamic potential) and anodic current onset potentials as low as -0.5 V_RHE. The herein-presented organic-based approach paves the way for further exploration of different blend combinations to target specific oxidative reactions by selecting precise donor/acceptor candidates among the multiple existing ones.

In recent years, perovskite light-emitting diodes have witnessed a remarkable evolution in both efficiency and luminance levels. Nonetheless, the production of such devices typically relies on protracted synthesis procedures at elevated temperatures and vacuum/inert conditions (e.g. hot-injection synthesis), thus rendering them technically unsuitable for extensive display and/or lighting applications manufacturing. Although alternative synthetic protocols have been proposed, e.g. ligand-assisted reprecipitation, ultrasonic and microwave-based methods, their suitability for the construction of high-performing light-emitting diodes has been reported in only a few studies. In this study, we demonstrate the fabrication of highly efficient lighting devices based on CsPbBr₃ colloidal perovskite nanocrystals synthesized by a fast, energetically efficient, and up-scalable microwave-assisted method. These nanocrystals exhibit an impressive photoluminescence quantum yield of 66.8% after purification, with a very narrow PL spectrum centered at 514 nm with a full width at half-maximum of 20 nm. Similarly, the PeLEDs achieve a maximum external quantum efficiency of 23.4%, a maximum current efficiency of 71.6 Cd A^-1, and a maximum luminance level that exceeds 4.7 × 10⁴ Cd m^-2. Additionally, a significantly lower energy consumption for microwave-mediated synthesis compared with hot injection is demonstrated. These findings suggest that this synthetic procedure emerges as an outstanding and promising method towards a scalable and sustainable fabrication of high-quality perovskite light-emitting diodes.

The search for safer next-generation lithium-ion batteries (LIBs) has driven significant research on non-toxic, non-flammable solid electrolytes. However, their electrochemical performance often falls short. This work presents a simple, one-step photopolymerization process for synthesizing biphasic liquid–solid ionogel electrolytes using acrylic acid monomer and P_111i4FSI ionic liquid. We investigated the impact of lithium salt concentration and temperature on ion diffusion, particularly lithium-ion (Li⁺) mobility, within these ionogels. Pulsed-field gradient nuclear magnetic resonance (PFG-NMR) revealed enhanced Li⁺ diffusion in the acrylic acid (AA)-based ionogels compared to their non-confined ionic liquid counterparts. Remarkably, Li⁺ diffusion remained favorable in the ionogels regardless of salt concentration. These AA-based ionogels demonstrate very good ionic conductivity (>1 mS cm^-1 at room temperature) and a wide electrochemical window (up to 5.3 V vs Li⁺/Li⁰). These findings suggest significant promise for AA-based ionogels as polymer solid electrolytes in future solid-state battery applications.

Triboelectric nanogenerators (TENGs) are emerging as new technologies to harvest electrical power from mechanical energy. With the distinctive working mechanism of triboelectric nanogenerators, they attract particular interest in healthcare monitoring, wearable electronics, and deformable energy harvesting, which raises the requirement for highly conformable devices with substantial energy outputs. Here, a simple, low-cost strategy for fabricating stretchable triboelectric nanogenerators with ultra-high electrical output is developed. The TENG is prepared using PTFE micron particles (PP-TENG), contributing a different electrostatic induction process compared to TENG based on dielectric films, which was associated with the dynamics of particle motions in PP-TENG. The generator achieved an impressive voltage output of 1000 V with a current of 25 µA over a contact area of 40 × 20 mm². Additionally, the TENG exhibits excellent durability with a stretching strain of 500%, and the electrical output performance does not show any significant degradation even after 3000 cycles at a strain of 400%. The unique design of the device provides high conformability and can be used as a self-powered sensor for human motion detection.

In this study, a framework for predicting the gas-sensitive properties of gas-sensitive materials by combining machine learning and density functional theory (DFT) has been proposed. The framework rapidly predicts the gas response of materials by establishing relationships between multisource physical parameters and gas-sensitive properties. In order to prove its effectiveness, the perovskite Cs₃Cu₂I₅ has been selected as the representative material. The physical parameters before and after the adsorption of various gases have been calculated using DFT, and then a machine learning model has been trained based on these parameters. Previous studies have shown that a single physical parameter alone is not enough to accurately predict the gas sensitivity of materials. Therefore, a variety of physical parameters have been selected for machine learning, and the final machine learning model achieved 92% accuracy in predicting gas sensitivity. It is important to note that although there have been no previous reports on the response of Cs₃Cu₂I₅ to hydrogen sulfide, the resulting model predicts the gas response of H₂S; it is subsequently confirmed experimentally. This method not only enhances the understanding of the gas sensing mechanism, but also has a universal nature, making it suitable for the development of various new gas-sensitive materials.

Seawater is the most abundant source of molecular hydrogen. Utilizing the hydrogen reserves present in the seawater may inaugurate innovative strategies aimed at advancing sustainable energy and environmental preservation endeavors in the future. Recently, there has been a surge in study in the field addressing the production of hydrogen through the electrochemical seawater splitting. However, the performance and durability of the electrode have limitations due to the fact that there are a few challenges that need to be addressed in order to make the technology suitable for the industrial purpose. The active site blockage caused by chloride ions that are prevalent in seawater and chloride corrosion is the most significant issue; it has a negative impact on both the activity and the durability of the anode component. Addressing this particular issue is of upmost importance in the seawater splitting area. This review concentrates on the newly developed materials and techniques for inhibiting chloride ions by blocking the active sites, simultaneously preventing the chloride corrosion. It is anticipated that the concept will be advantageous for a large audience and will inspire researchers to study on this particular area of concern.

Thermoelectric materials, capable of converting temperature gradients into electrical power, have been traditionally limited by a trade-off between thermopower and electrical conductivity. This study introduces a novel, broadly applicable approach that enhances both the spin-driven thermopower and the thermoelectric figure-of-merit (zT) without compromising electrical conductivity, using temperature-driven spin crossover. Our approach, supported by both theoretical and experimental evidence, is demonstrated through a case study of chromium doped-manganese telluride, but is not confined to this material and can be extended to other magnetic materials. By introducing dopants to create a high crystal field and exploiting the entropy changes associated with temperature-driven spin crossover, we achieved a significant increase in thermopower, by approximately 136 µV K^-1, representing more than a 200% enhancement at elevated temperatures within the paramagnetic domain. Our exploration of the bipolar semiconducting nature of these materials reveals that suppressing bipolar magnon/paramagnon-drag thermopower is key to understanding and utilizing spin crossover-driven thermopower. These findings, validated by inelastic neutron scattering, X-ray photoemission spectroscopy, thermal transport, and energy conversion measurements, shed light on crucial material design parameters. We provide a comprehensive framework that analyzes the interplay between spin entropy, hopping transport, and magnon/paramagnon lifetimes, paving the way for the development of high-performance spin-driven thermoelectric materials.

The replacement of non-aqueous organic electrolytes with solid-state electrolytes (SSEs) in solid-state lithium metal batteries (SLMBs) is considered a promising strategy to address the constraints of lithium-ion batteries, especially in terms of energy density and reliability. Nevertheless, few SLMBs can deliver the required cycling performance and long-term stability for practical use, primarily due to suboptimal interface properties. Given the diverse solidification pathways leading to different interface characteristics, it is crucial to pinpoint the source of interface deterioration and develop appropriate remedies. This review focuses on Li|SSE interface issues between lithium metal anode and SSE, discussing recent advancements in the understanding of (electro)chemistry, the impact of defects, and interface evolutions that vary among different SSE species. The state-of-the-art strategies concerning modified SEI, artificial interlayer, surface architecture, and composite structure are summarized and delved into the internal relationships between interface characteristics and performance enhancements. The current challenges and opportunities in characterizing and modifying the Li|SSE interface are suggested as potential directions for achieving practical SLMBs.

Point source CO₂ capture (PSCC) is crucial for decarbonizing various industrial sectors, while direct air capture (DAC) holds promise for removing CO₂ directly from the air. Sorbents play a critical role in both technologies, with their performances, efficiency, cost, etc., largely depending on which type is used (physical or chemical). Solid amine sorbents (SAS) employed in the chemical adsorption of CO₂ are suitable for both PSCC and DAC. SAS offer significant advantages over liquid amines such as monoethanolamine (MEA), due to their ability to perform cyclic adsorption–desorption with much lower energy requirement. The environmental concern associated with MEA can be mitigated by SAS. Support materials have a significantly important role in stabilizing amine and enhancing stability and kinetics; varieties of support materials have been screened at a laboratory scale. One promising support material is a silica gel (SG), which is commercially available and attractive for designing cost-effective sorbents for large-scale CO₂ capture. Various impregnation methods such as physical adsorption and covalent functionalization have been employed to functionalize silica surfaces with amines. This review provided a comprehensive critical analysis of SG-based SAS for CO₂ capture. We discussed and evaluated them in terms of their adsorption capacity, adsorption, and desorption conditions, and the kinetics involved in these processes. Finally, we proposed a few recommendations for further development of low-cost, lower carbon footprint SAS for large-scale deployment of CO₂ capture technology.

Piezocomposites with both flexibility and electromechanical conversion characteristics have been widely applied in various fields, including sensors, energy harvesting, catalysis, and biomedical treatment. In the composition of piezocomposites or their preparation process, a category of materials is commonly employed that do not possess piezoelectric properties themselves but play a crucial role in performance enhancement. In this review, the concept of auxiliary phase is first proposed to define these materials, aiming to provide a new perspective for designing high-performance piezocomposites. Three different categories of modulation forms of auxiliary phase in piezocomposites are systematically summarized, including the modification of piezo-matrix, the modification of piezo-fillers, and the construction of special structures. Each category emphasizes the role of the auxiliary phase and systematically discusses the latest advancements and the physical mechanisms of the auxiliary phase enhanced flexible piezocomposites. Finally, a summary and future outlook of piezocomposites based on the auxiliary phase are provided.