Ensuring a stable power output from renewable energy sources, such as wind and solar energy, depends on the development of large-scale and long-duration energy storage devices. Zinc–bromine flow batteries (ZBFBs) have emerged as cost-effective and high-energy-density solutions, replacing expensive all-vanadium flow batteries. However, uneven Zn deposition during charging results in the formation of problematic Zn dendrites, leading to mass transport polarization and self-discharge. Stable Zn plating and stripping are essential for the successful operation of high-areal-capacity ZBFBs. In this study, we successfully synthesized nitrogen and oxygen co-doped functional carbon felt (NOCF4) electrode through the oxidative polymerization of dopamine, followed by calcination under ambient conditions. The NOCF4 electrode effectively facilitates efficient “shuttle deposition” of Zn during charging, significantly enhancing the areal capacity of the electrode. Remarkably, ZBFBs utilizing NOCF4 as the anode material exhibited stable cycling performance for 40 cycles (approximately 240 h) at an areal capacity of 60 mA h/cm². Even at a high areal capacity of 130 mA h/cm², an impressive energy efficiency of 76.98% was achieved. These findings provide a promising pathway for the development of high-areal-capacity ZBFBs for advanced energy storage systems.

Recently, electronic skins and flexible wearable devices have been developed for widespread applications in medical monitoring, artificial intelligence, human–machine interaction, and artificial prosthetics. Flexible proximity sensors can accurately perceive external objects without contact, introducing a new way to achieve an ultrasensitive perception of objects. This article reviews the progress of flexible capacitive proximity sensors, flexible triboelectric proximity sensors, and flexible gate-enhanced proximity sensors, focusing on their applications in the electronic skin field. Herein, their working mechanism, materials, preparation methods, and research progress are discussed in detail. Finally, we summarize the future challenges in developing flexible proximity sensors.

Recently, rechargeable aqueous zinc-based batteries using manganese oxide as the cathode (e.g., MnO₂) have gained attention due to their inherent safety, environmental friendliness, and low cost. Despite their potential, achieving high energy density in Zn||MnO₂ batteries remains challenging, highlighting the need to understand the electrochemical reaction mechanisms underlying these batteries more deeply and optimize battery components, including electrodes and electrolytes. This review comprehensively summarizes the latest advancements for understanding the electrochemistry reaction mechanisms and designing electrodes and electrolytes for Zn||MnO₂ batteries in mildly and strongly acidic environments. Furthermore, we highlight the key challenges hindering the extensive application of Zn||MnO₂ batteries, including high-voltage requirements and areal capacity, and propose innovative solutions to overcome these challenges. We suggest that MnO₂/Mn²⁺ conversion in neutral electrolytes is a crucial aspect that needs to be addressed to achieve high-performance Zn||MnO₂ batteries. These approaches could lead to breakthroughs in the future development of Zn||MnO₂ batteries, offering a more sustainable, cost-effective, and high-performance alternative to traditional batteries.

CO₂ is the most cost-effective and abundant carbon resource, while the reverse water–gas reaction (rWGS) is one of the most effective methods of CO₂ utilization. This work presents a comparative study of rWGS activity for perovskite systems based on AFeO₃ (where A = Ce, La, Y). These systems were synthesized by solution combustion synthesis (SCS) with different ratios of fuel (glycine) and oxidizer (φ), different amounts of NH₄NO₃, and the addition of alumina or silica as supports. Various techniques, including X-ray diffraction analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, energy-dispersive X-ray spectroscopy, N₂-physisorption, H₂ temperature-programmed reduction, temperature-programmed desorption of H₂ and CO₂, Raman spectroscopy, and in situ FTIR, were used to relate the physicochemical properties with the catalytic performance of the obtained composites. Each specific perovskite-containing system (either bulk or supported) has its own optimal φ and NH₄NO₃ amount to achieve the highest yield and dispersion of the perovskite phase. Among all synthesized systems, bulk SCS-derived La–Fe–O systems showed the highest resistance to reducing environments and the easiest hydrogen desorption, outperforming La–Fe–O produced by solgel combustion (SGC). CO₂ conversion into CO at 600 °C for bulk ferrite systems, depending on the A-cation type and preparation method, follows the order La (SGC) < Y < Ce < La (SCS). The differences in properties between La–Fe–O obtained by the SCS and SGC methods can be attributed to different ratios of oxygen and lanthanum vacancy contributions, hydroxyl coverage, morphology, and free iron oxide presence. In situ FTIR data revealed that CO₂ hydrogenation occurs through formates generated under reaction conditions on the bulk system based on La–Fe–O, obtained by the SCS method. γ-Al₂O₃ improves the dispersion of CeFeO₃ and LaFeO₃ phases, the specific surface area, and the quantity of adsorbed H₂ and CO₂. This led to a significant increase in CO₂ conversion for supported CeFeO₃ but not for the La-based system compared to bulk and SiO₂-supported perovskite catalysts. However, adding alumina increased the activity per mass for both Ce- and La-based perovskite systems, reducing the amount of rare-earth components in the catalyst and thereby lowering the cost without substantially compromising stability.

With the rapid development of plastic production and consumption globally, the amount of post-consumer plastic waste has reached levels that have posed environmental threats. Considering the substantial CO₂ emissions throughout the plastic lifecycle from material production to its disposal, photocatalysis is considered a promising strategy for effective plastic recycling and upcycling. It can upgrade plastics into value-added products under mild conditions using solar energy, realizing zero carbon emissions. In this paper, we explain the basics of photocatalytic plastic reformation and underscores plastic feedstock reformation pathways into high-value-added products, including both degradation into CO₂ followed by reformation and direct reformation into high-value-added products. Finally, the current applications of transforming plastic waste into fuels, chemicals, and carbon materials and the outlook on upcycling plastic waste by photocatalysis are presented, facilitating the realization of carbon neutrality and zero plastic waste.

N-doped carbon materials, with their applications as electrocatalysts for the oxygen reduction reaction (ORR), have been extensively studied. However, a negletcted fact is that the operating potential of the ORR is higher than the theoretical oxidation potential of carbon, possibly leading to the oxidation of carbon materials. Consequently, the influence of the structural oxidation evolution on ORR performance and the real active sites are not clear. In this study, we discover a two-step oxidation process of N-doped carbon during the ORR. The first oxidation process is caused by the applied potential and bubbling oxygen during the ORR, leading to the oxidative dissolution of N and the formation of abundant oxygen-containing functional groups. This oxidation process also converts the reaction path from the four-electron (4e) ORR to the two-electron (2e) ORR. Subsequently, the enhanced 2e ORR generates oxidative H₂O₂, which initiates the second stage of oxidation to some newly formed oxygen-containing functional groups, such as quinones to dicarboxyls, further diversifying the oxygen-containing functional groups and making carboxyl groups as the dominant species. We also reveal the synergistic effect of multiple oxygen-containing functional groups by providing additional opportunities to access active sites with optimized adsorption of OOH*, thus leading to high efficiency and durability in electrocatalytic H₂O₂ production.

Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups (e.g., C=C and C=O) is a promising yet challenging endeavor. In our study, we developed a Pd/CeO₂ catalyst by enhancing the oxygen vacancy (O_V) concentration in CeO₂ through high-temperature treatment. This process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl stearate. Specifically, metal Pd⁰ atoms bonded to the O_V in defective CeO₂ formed Pd⁰–O_V–Ce³⁺ interfacial sites, enabling strong electron transfer from CeO₂ to Pd. The interfacial sites exhibit a synergistic adsorption effect on the reaction substrate. Pd⁰ sites promote the adsorption and activation of C=C bonds, while O_V preferably adsorbs C=O bonds, mitigating competition with C=C bonds for Pd⁰ adsorption sites. This synergy ensures rapid C=C bond activation and accelerates the attack of active H* species on the semi-hydrogenated intermediate. As a result, our Pd/CeO₂-500 catalyst, enriched with Pd⁰–O_V–Ce³⁺ interfacial sites, demonstrated excellent hydrogenation activity at just 30 °C. The catalyst achieved a Cis–C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g_metal). This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.

The existence of alkali metals in flue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction (SCR) of nitrogen oxides (NO _x). It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts. Therefore, in this study, a series of CoMn catalysts doped with heteropolyacids (HPAs) were prepared using the coprecipitation method. Among these, CoMnHPMo exhibited superior catalytic performance for SCR and over 95% NO _x conversion at 150–300 ℃. Moreover, it exhibited excellent catalytic activity and stability after alkali poisoning, demonstrating outstanding alkali metal resistance. The characterization indicated that HPMo increased the specific surface area of the catalyst, which provided abundant adsorption sites for NO _x and NH₃. Comparing catalysts before and after poisoning, CoMnHPMo enhanced its alkali metal resistance by sacrificing Brønsted acid sites to protect its Lewis acid sites. In situ DRIFTS was used to study the reaction pathways of the catalysts. The results showed that CoMnHPMo maintained high NH₃ adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered. Consequently, SCR performance was ensured even after alkali metal poisoning. In summary, this research proposed a simple method for the design of an alkali-resistant NH₃-SCR catalyst with high activity at low temperatures.

Although doped hole-transport materials (HTMs) offer an efficiency benefit for perovskite solar cells (PSCs), they inevitably diminish the stability. Here, we describe the use of various chlorinated small molecules, specifically fluorenone-triphenylamine (FO-TPA)-x-Cl [x = para, meta, and ortho (p, m, and o)], with different chlorine-substituent positions, as dopant-free HTMs for PSCs. These chlorinated molecules feature a symmetrical donor–acceptor–donor structure and ideal intramolecular charge transfer properties, allowing for self-doping and the establishment of built-in potentials for improving charge extraction. Highly efficient hole-transfer interfaces are constructed between perovskites and these HTMs by strategically modifying the chlorine substitution. Thus, the chlorinated HTM-derived inverted PSCs exhibited superior efficiencies and air stabilities. Importantly, the dopant-free HTM FO-TPA-o-Cl not only attains a power conversion efficiency of 20.82% but also demonstrates exceptional stability, retaining 93.8% of its initial efficiency even after a 30-day aging test conducted under ambient air conditions in PSCs without encapsulation. These findings underscore the critical role of chlorine-substituent regulation in HTMs in ensuring the formation and maintenance of efficient and stable PSCs.

Herein, a novel method for fluorometric detection of soybean trypsin inhibitor (SBTI) activity based on a water-soluble poly(diphenylacetylene) derivative was reported. Fluorescence quenching of the polymer via p-nitroaniline, produced from the trypsin-catalyzed decomposition of N-benzoyl-DL-arginine-4-nitroanilide hydrochloride (L-BAPA), was well described using the Stern–Volmer equation. SBTI activity was quantitatively assessed based on changes in the fluorescence intensity of the polymer. This strategy has several advantages, such as high sensitivity and ease of operation. Moreover, its applicability to other biochemical analyses is promising.

Electrocatalytic semi-hydrogenation of acetylene (C₂H₂) over copper nanoparticles (Cu NPs) offers a promising non-petroleum alternative for the green production of ethylene (C₂H₄). However, server hydrogen evolution reaction (HER) competition in this process prominently decreases C₂H₄ selectivity, thereby hindering its practical application. Herein, a Cu-based composite catalyst, wherein porous carbon with nanoscale pores was used as a support, is constructed to gather the C₂H₂ feedstocks for suppressing the undesirable HER. As a result, the as-prepared catalyst exhibited C₂H₂ conversion of 27.1% and C₂H₄ selectivity of 88.4% at a C₂H₄ partial current density of 0.25 A/cm² under optimal − 1.0 V versus reversible hydrogen electrode (RHE) under the simulated coal-derived C₂H₂ atmosphere, significantly outperforming the single Cu NPs counterparts. In addition, a series of in situ and ex situ experimental results show that not only the porous nature of the carbon support but also the stabilized Cu⁰–Cu⁺ dual active sites through the strong metal–support interactions enhance the adsorption capacity of C₂H₂, leading to high C₂H₂ partial pressure, restraining the HER and thus improving the C₂H₄ selectivity.

Because of the low reactivity of cyclic nitrides, liquid-phase synthesis of carbon nitride introduces challenges despite its favorable potential for energy-efficient preparation and superior applications. In this study, we demonstrate a strong interaction between citric acid and melamine through experimental observation and theoretical simulation, which effectively activates melamine-condensation activity and produces carbon-rich carbon nitride nanosheets (CCN NSs) during hydrothermal reaction. Under a large specific surface area and increased light absorption, these CCN NSs demonstrate significantly enhanced photocatalytic activity in CO₂ reduction, increasing the CO production rate by approximately tenfold compared with hexagonal melamine (h-Me). Moreover, the product selectivity of CCN NSs reaches up to 93.5% to generate CO from CO₂. Furthermore, the annealed CCN NSs exhibit a CO conversion rate of up to 95.30 μmol/(g h), which indicates an 18-fold increase compared with traditional carbon nitride. During the CCN NS synthesis, nitrogen-doped carbon quantum dots (NDC QDs) are simultaneously produced and remain suspended in the supernatant after centrifugation. These QDs disperse well in water and exhibit excellent luminescent properties (QY = 67.2%), allowing their application in the design of selective and sensitive sensors to detect pollutants such as pesticide 2,4-dichlorophenol with a detection limit of as low as 0.04 µmol/L. Notably, the simultaneous synthesis of CCN NSs and NDC QDs provides a cost-effective and highly efficient process, yielding products with superior capabilities for catalytic conversion of CO₂ and pollutant detection, respectively.

A major challenge is to construct ceramic membranes with tunable structures and functions for water treatment. Herein, a novel corrosion-resistant polymer-derived silicon oxycarbide (SiOC) ceramic membrane with designed architectures was fabricated by a phase separation method and was applied in organic removal via adsorption and oxidation for the first time. The pore structure of the as-prepared SiOC ceramic membranes was well controlled by changing the sintering temperature and polydimethylsiloxane content, leading to a pore size of 0.84–1.62 μm and porosity of 25.0–43.8%. Corrosion resistance test results showed that the SiOC membranes sustained minimal damage during 24 h exposure to high-intensity acid–base conditions, which could be attributed to the chemical inertness of SiOC. With rhodamine 6G (R6G) as the model pollutant, the SiOC membrane demonstrated an initial effective removal rate of 99% via adsorption; however, the removal rate decreased as the system approached adsorption saturation. When peroxymonosulfate was added into the system, efficient and continuous degradation of R6G was observed throughout the entire period, indicating the potential of the as-prepared SiOC membrane in oxidation-related processes. Thus, this work provides new insights into the construction of novel polymer-derived ceramic membranes with well-defined structures and functions.

PPMG-based composite electrolytes were fabricated via the solution method using the polyvinyl alcohol and polyvinylpyrrolidone blend reinforced with various contents of sulfonated inorganic filler. Sulfuric acid was employed as the sulfonating agent to functionalize the external surface of the inorganic filler, i.e., graphene oxide. The proton conductivities of the newly prepared proton exchange membranes (PEMs) were increased by increasing the temperature and content of sulfonated graphene oxide (SGO), i.e., ranging from 0.025 S/cm to 0.060 S/cm. The induction of the optimum level of SGO is determined to be an excellent route to enhance ionic conductivity. The single-cell performance test was conducted by sandwiching the newly prepared PEMs between an anode (0.2 mg/cm² Pt/Ru) and a cathode (0.2 mg/cm² Pt) to prepare membrane electrode assemblies, followed by hot pressing under a pressure of approximately 100 kg/cm² at 60 °C for 5–10 min. The highest power densities achieved with PPMG PEMs were 14.9 and 35.60 mW/cm² at 25 °C and 70 °C, respectively, at ambient pressure with 100% relative humidity. Results showed that the newly prepared PEMs exhibit good electrochemical performance. The results indicated that the prepared composite membrane with 6 wt% filler can be used as an alternative membrane for applications of high-performance proton exchange membrane fuel cell.

All-solid-state lithium-metal batteries (ASSLMBs) are widely considered as the ultimately advanced lithium batteries owing to their improved energy density and enhanced safety features. Among various solid electrolytes, sulfide solid electrolyte (SSE) Li₆PS₅Cl has garnered significant attention. However, its application is limited by its poor cyclability and low critical current density (CCD). In this study, we introduce a novel approach to enhance the performance of Li₆PS₅Cl by doping it with fluorine, using lithium fluoride nanoparticles (LiFs) as the doping precursor. The F-doped electrolyte Li₆PS₅Cl-0.2LiF(nano) shows a doubled CCD, from 0.5 to 1.0 mA/cm² without compromising the ionic conductivity; in fact, conductivity is enhanced from 2.82 to 3.30 mS/cm, contrary to the typical performance decline seen in conventionally doped Li₆PS₅Cl electrolytes. In symmetric Li|SSE|Li cells, the lifetime of Li₆PS₅Cl-0.2LiF(nano) is 4 times longer than that of Li₆PS₅Cl, achieving 1500 h vs. 371 h under a charging/discharging current density of 0.2 mA/cm². In Li|SSE|LiNbO₃@NCM721 full cells, which are tested under a cycling rate of 0.1 C at 30 °C, the lifetime of Li₆PS₅Cl-0.2LiF(nano) is four times that of Li₆PS₅Cl, reaching 100 cycles vs. 26 cycles. Therefore, the doping of nano-LiF offers a promising approach to developing high-performance Li₆PS₅Cl for ASSLMBs.