The achievement of a carbon-neutral energy economy is nowadays mandatory to face global warming and the current energy crisis. To mitigate the present and future environmental issues, replacing fossil feedstocks with renewable sources is of primary importance, aiming to meet future generations’ demands for energy and commodities. In light of this, the revamp of the ammonia synthesis, which today consumes almost 2% of the energy globally produced, gained increasing interest. The ammonia generation by reacting air and water and using sunlight as an inexhaustible source of energy is the closest approach to the ideal situation for zero-carbon energy and chemical production. To promote solar-to-ammonia production, the photocatalyst plays a crucial role. However, for large-scale implementation and long-term utilization, the selection of noncritical raw materials in catalyst preparation is central aiming at resource security. In this context, herein are reviewed different strategies developed to improve the photocatalytic performances of carbon-based materials. The introduction of vacancies and surface doping are discussed as valuable approaches to enhance the photocatalytic activity in the nitrogen fixation reactions, as well as the construction of heterojunctions to finely tune the electronic properties of carbon-based materials.

Reducing our carbon footprint is one of the most pressing issues facing humanity today. The technology of Li-rechargeable batteries is permeating every corner of our lives as a result of our efforts to reduce the use of carbon energy. Batteries can be seen metaphorically as “living cells”, and approaching the future of that technology requires observing and understanding the real-time phenomena that occur inside battery systems during (electro)chemical reactions. In this regard, in situ analysis techniques have made significant progress toward understanding the basic science of battery systems and finding better performance-improving factors. There are various analysis methods utilizing electromagnetic waves, electrons, and neutrons to perform multifaceted analyses of battery systems from the atomic to the macroscopic scale. Now is the opportune moment to construct a comprehensive guide that facilitates the design of advanced Li-rechargeable battery systems, adopting a highly discerning and all-encompassing approach toward these cutting-edge technologies. In this review article, we discuss and organize the key components such as capabilities, limitations, and practical tips with a comprehensive perspective on various in situ techniques. Moreover, this article covers a wide range of information from the nano to the micrometer scale, such as electronic, atomic, crystal, and morphological structures, from stereoscopic perspectives considering the probing depth.

Semicoke, a coal pyrolysis product, is a cost-effective and high-yield precursor for hard carbon used as anode in sodium-ion batteries (SIBs). However, as a thermoplastic precursor, semicoke inevitably graphitizes during high-temperature carbonization, so it is not easy to form the hard carbon structure. Herein, we propose an oxidation-crosslinking strategy to realize fusion-to-solid-state pyrolysis of semicoke. The semicoke is first preoxidized using a modified alkali-oxygen oxidation method to enrich its surface with carboxyl groups, which are localization points and the cross-linking reactions occur with citric acid to build the semicoke precursor with homogeneous and abundant -C-(O)–O- groups (up to 21 at% oxygen content). The -C-(O)–O- groups effectively prevent the rearrangement of carbon microcrystals in semicoke during carbonization, resulting in the formation of an abundant pseudographite structure with larger carbon interlayer spacing and micropores. The optimized semicoke-based hard carbon shows both a high initial Coulombic efficiency of 81% and a specific capacity of 307 mAh g^–1, with low-voltage plateau capacity increased to 2.5 times, compared to that of the unmodified semicoke carbon. By the combination of detailed discharge curves and in situ X-ray diffraction analysis, the plateau capacity of semicoke-based hard carbon is mainly derived from interlayer intercalation of Na⁺ ion. The proposed oxidation-crosslinking strategy can contribute to the usage of low-cost and high-performance hard carbons in advanced SIBs.

Due to the advantages of cost-effectiveness and tunable band gap, hole transport layer (HTL)-free CsPbI_XBr_3–X carbon-based inorganic perovskite solar cells (C-IPSCs) are emerging candidates for both single junction and tandem solar cells. Because of the direct contact between the carbon electrode and the perovskite surface, energy barriers and defects at the interface limit the enhancement of power conversion efficiency (PCE). In this work, we first reported a preparation method of CsPbI_2.75Br_0.25 HTL-free C-IPSCs and developed an effective surface sulfidation regulation (SSR) strategy to promote hole extraction and inhibit non-radiative recombination of inorganic perovskite by 2-(thiocyanomethylthio)benzothiazole (TCMTB) surface modification. The introduced S^2– anions form strong binding with uncoordinated Pb ions, inhibit the perovskite degradation reaction, and effectively passivate the surface defects. In addition, PbS formed by the SSR strategy constructed a gradient heterojunction, which promoted the arrangement energy levels and enhanced hole extraction. An additional back-surface field is induced at the interface of perovskite by energy band bending, which increases the open-circuit voltage (V_OC). As a result, the SSR-based CsPbI_2.75Br_0.25 HTL-free C-IPSCs showed a PCE of 17.88% with a fill factor of 81.56% and V_OC of 1.19 V, which was among the highest reported values of CsPbI_2.75Br_0.25 HTL-free C-IPSCs.

Lithium–oxygen (Li–O₂) batteries are an emerging energy storage alternative with the potential to meet the recent increase in demand for high-energy-density batteries. From a practical viewpoint, lithium–air (Li–Air) batteries using ambient air instead of pure oxygen could be the final goal. However, the slow oxygen reduction and evolution reactions interfere with reversible cell operation during cycling. Therefore, research continues to explore various catalyst materials. The present study attempts to improve the performance of Li–Air batteries by using porphyrin-based materials known to have catalytic effects in Li–O₂ batteries. The results confirm that the iron phthalocyanine (FePc) catalyst not only exhibits a catalytic effect in an air atmosphere with a low oxygen fraction but also suppresses electrolyte decomposition by stabilizing superoxide radical ions (O₂^–) at a high voltage range. Density functional theory calculations are used to gain insight into the exact FePc-mediated catalytic mechanism in Li–Air batteries, and various ex situ and in situ analyses reveal the reversible reactions and structural changes in FePc during electrochemical reaction. This study provides a practical solution to ultimately realize an air-breathing battery using nature-friendly catalyst materials.

Electrochemical CO₂ reduction reaction (CO₂RR) offers a promising strategy for CO₂ conversion into value-added C₂₊ products and facilitates the storage of renewable resources under comparatively mild conditions, but still remains a challenge. Herein, we propose the strategy of surface reconstruction and interface integration engineering to construct tuneable Cu⁰–Cu⁺–Cu²⁺ sites and oxygen vacancy oxide derived from CeO₂/CuO nanosheets (OD-CeO₂/CuO NSs) heterojunction catalysts and promote the activity and selectivity of CO₂RR. The optimized OD-CeO₂/CuO electrocatalyst shows the maximum Faradic efficiencies for C₂₊ products in the H-type cell, which reaches 69.8% at –1.25 V versus a reversible hydrogen electrode (RHE). Advanced characterization analysis and density functional theory (DFT) calculations further confirm the fact that the existence of oxygen vacancies and Cu⁰–Cu⁺–Cu²⁺ sites modified with CeO₂ is conducive to CO₂ adsorption and activation, enhances the hydrogenation of *CO to *CHO, and further promotes the dimerization of *CHO, thus promoting the selectivity of C₂₊ generation. This facile interface integration and surface reconstruction strategy provides an ideal strategy to guide the design of CO₂RR electrocatalysts.

Sodium (Na) metal stands out as a highly promising anode material for high-energy-density Na batteries owing to its abundant resources and exceptional theoretical capacity at low redox potential. Nevertheless, the uncontrolled growth of Na dendrites and the accompanying volumetric changes during the plating/stripping process lead to safety concerns and poor electrochemical performances. This study introduces nitrogen and oxygen co-doped carbon nanofiber networks wrapped carbon felt (NO-CNCF), serving as Na deposition skeletons to facilitate a highly reversible Na metal anode. The NO-CNCF framework with uniformly distributed “sodiophilic” functional groups, nanonetwork protuberances, and cross-linked network scaffold structure can avoid charge accumulation and facilitate the dendrite-free Na deposition. Benefiting from these features, the NO-CNCF@Na symmetrical cells demonstrate notable enhancements in cycling stability, achieving 4000 h cycles at 1 mA cm^–2 for 1 mAh cm^–2 and 2400 h cycles at 2 mA cm^–2 for 2 mAh cm^–2 with voltage overpotential of approximately 6 and 10 mV, respectively. Furthermore, the NVP//NO-CNCF@Na full cells achieve stable cycling performance and favorable rate capability. This investigation offers novel insights into fabricating a “sodiophilic” matrix with a multistage structure toward high-performance Na metal batteries.

The current collector is a crucial component in lithium-ion batteries and supercapacitor setups, responsible for gathering electrons from electrode materials and directing them into the external circuit. However, as battery systems evolve and the demand for higher energy density increases, the limitations of traditional current collectors, such as high contact resistance and low corrosion resistance, have become increasingly evident. This review investigates the functions and challenges associated with current collectors in modern battery and supercapacitor systems, with a particular focus on using carbon coating methods to enhance their performance. Surface coating, known for its simplicity and wide applicability, emerges as a promising solution to address these challenges. The review provides a comprehensive overview of carbon-coated current collectors across various types of metal and nonmetal substrates in lithium-ion batteries and supercapacitors, including a comparative analysis of coating materials and techniques. It also discusses methods for manufacturing carbon-coated current collectors and their practical implications for the industry. Furthermore, the review explores prospects and opportunities, highlighting the development of next-generation high-performance coatings and emphasizing the importance of advanced current collectors in optimizing energy device performance.

Despite considerable efforts to develop electrolyzers for energy conversion, progress has been hindered during the implementation stage by different catalyst development requirements in academic and industrial research. Herein, a coherent workflow for the efficient transition of electrocatalysts from basic research to application readiness for the alkaline oxygen evolution reaction is proposed. To demonstrate this research approach, La_0.8Sr_0.2CoO₃ is selected as a catalyst, and its electrocatalytic performance is compared with that of the benchmark material NiFe₂O₄. The La_0.8Sr_0.2CoO₃ catalyst with the desired dispersity is successfully synthesized by scalable spray-flame synthesis. Subsequently, inks are formulated using different binders (Nafion^®, Naf; Sustainion^®, Sus), and nickel substrates are spray coated, ensuring a homogeneous catalyst distribution. Extensive electrochemical evaluations, including several scale-bridging techniques, highlight the efficiency of the La_0.8Sr_0.2CoO₃ catalyst. Experiments using the scanning droplet cell (SDC) indicate good lateral homogeneity for La_0.8Sr_0.2CoO₃ electrodes and NiFe₂O₄-Sus, while the NiFe₂O₄-Naf film suffers from delamination. Among the various half-cell techniques, SDC proves to be a valuable tool to quickly check whether a catalyst layer is suitable for full-cell-level testing and will be used for the fast-tracking of catalysts in the future. Complementary compression and flow cell experiments provide valuable information on the electrodes’ behavior upon exposure to chemical and mechanical stress. Finally, parameters and conditions simulating industrial settings are applied using a zero-gap cell. Findings from various research fields across different scales obtained based on the developed coherent workflow contribute to a better understanding of the electrocatalytic system at the early stages of development and provide important insights for the evaluation of novel materials that are to be used in large-scale industrial applications.

Carbonitride MXenes, such as Ti₃CNT_x, Ti₂C_0.5N_0.5T_x, and Ti₄(C_0.2N_0.8)₃T_x, have attracted much interest in the large family of two-dimensional (2D) nanomaterials. Like their carbide MXene counterparts, the nanolayered structure and functional groups endow carbonitride MXenes with an attractive combination of physical and chemical properties. More interestingly, the replacement of C by N changes the lattice parameters and electron distribution of carbonitride MXenes due to the greater electronegativity of N as compared to C, thus resulting in significantly enhanced functional properties. This paper reviews the development of carbonitride MXenes, the preparation of 2D carbonitride MXenes, and the current understanding of the microstructure, electronic structure, and functional properties of carbonitride MXenes. In addition, applications, especially in energy storage, sensors, catalysts, electromagnetic wave shielding and absorption, fillers, and environmental and biomedical fields, are summarized. Finally, their current limitations and future opportunities are presented.

Anode-free all-solid-state batteries (AF-ASSBs) have received significant attention as a next-generation battery system due to their high energy density and safety. However, this system still faces challenges, such as poor Coulombic efficiency and short-circuiting caused by Li dendrite growth. In this study, the AF-ASSBs are demonstrated with reliable and robust electrochemical properties by employing Cu–Sn nanotube (NT) thin layer (∼1 µm) on the Cu current collector for regulating Li electrodeposition. Li_xSn phases with high Li-ion diffusivity in the lithiated Cu–Sn NT layer enable facile Li diffusion along with its one-dimensional hollow geometry. The unique structure, in which Li electrodeposition takes place between the Cu–Sn NT layer and the current collector by the Coble creep mechanism, improves cell durability by preventing solid electrolyte (SE) decomposition and Li dendrite growth. Furthermore, the large surface area of the Cu–Sn NT layer ensures close contact with the SE layer, leading to a reduced lithiation overpotential compared to that of a flat Cu–Sn layer. The Cu–Sn NT layer also maintains its structural integrity owing to its high mechanical properties and porous nature, which could further alleviate the mechanical stress. The LiNi_0.8Co_0.1Mn_0.1O₂ (NCM)|SE|Cu–Sn NT@Cu cell with a practical capacity of 2.9 mAh cm^–2 exhibits 83.8% cycle retention after 150 cycles and an average Coulombic efficiency of 99.85% at room temperature. It also demonstrates a critical current density 4.5 times higher compared to the NCM|SE|Cu cell.

Two-dimensional porous carbon nanosheets (PCNSs) are considered promising anodes for lithium-ion batteries due to their synergetic features arising from both graphene and porous structures. Herein, using naturally abundant and biocompatible sodium humate (SH) as the precursor, PCNSs are prepared from the laboratory scale up to the kilogram scale by a method of a facile ice-templating-induced puzzle coupled with a carbonization strategy. Such obtained SH-derived PCNSs (SH-PCNSs) possess a hierarchical porous structure dominated by mesopores having a specific surface area (∼127.19 ² g^–1), pore volume (∼0.134 cm³ g^–1), sheet-like morphology (∼2.18 nm in thickness), and nitrogen/oxygen-containing functional groups. Owing to these merits, the SH-PCNSs present impressive Li-ion storage characteristics, including high reversible capacity (1011 mAh g^–1 at 0.1 A g^–1), excellent rate capability (465 mAh g^–1 at 5 A g^–1), and superior cycle stability (76.8% capacitance retention after 1000 cycles at 5 A g^–1). It is noted that the SH-PCNSs prepared from the kilogram-scale production procedure possess comparable electrochemical properties. Furthermore, coupling with a LiNi_1/3Co_1/3Mn_1/3O₂ cathode, the full cells deliver a high capacity of 167 mAh g^–1 at 0.2 A g^–1 and exhibit an outstanding energy density of 128.8 Wh kg^–1, highlighting the practicability of this porous carbon nanosheets and the potential commercial opportunity of the scalable processing approach.

Investigating the activation of the persulfate process through heterogeneous carbonaceous catalysts to expedite the reduction of uranyl ions (U(VI)) is imperative. The primary hurdle involves understanding the transfer and distribution of photogenerated carriers during the reduction process in this intricate system and deciphering the role of activated groups in promoting reduction efficiency. In this study, we strategically regulate the structure of polymeric carbon nitride to promote the N-doped state, thereby facilitating delocalization electron enrichment. The resulting active sites effectively activate peroxyl disulfate (PDS), generating radicals that expedite the selective reduction of U(VI). This strategic approach mitigates the inherent disadvantage of the short half-life of free radicals in persulfate-based advanced oxidation processes. As a consequence of our endeavors and with the simultaneous presence of PDS and hydrogen peroxide, we achieve an exceptional photoreduction efficiency of 100% within a remarkably short period of 20 min. This breakthrough presents a high-efficiency application with significant potential for addressing the pollution associated with uranyl-containing wastewater. Our findings not only contribute to the fundamental understanding of AOPs but also offer a practical solution with implications for environmental remediation.

One-dimensional (1D) metals are well known for their exceptional conductivity and their ease of formation of interconnected networks that facilitate electron migration, making them promising candidates for electromagnetic (EM) attenuation. However, the impedance mismatch from high conductivity and their singular mode of energy loss hinder effective EM wave dissipation. Construction of cable structures not only optimizes impedance matching but also introduces a multitude of heterojunctions, increasing attenuation modes and potentially enhancing EM wave absorption (EMA) performance. Herein, we showcase the scalable synthesis of tin (Sn) whiskers from a Ti₂SnC MAX phase precursor, followed by creation of a 1D tin@carbon (Sn@C) cable structure through polymerization of PDA on their surface and annealing in argon. The EMA capabilities of Sn@C significantly surpass those of uncoated Sn whiskers, with an effective absorption bandwidth reaching 7.4 GHz. Remarkably, its maximum radar cross section reduction value of 27.85 dB m² indicates its exceptional stealth capabilities. The enhanced EMA performance is first attributed to optimized impedance matching, and furthermore, the Sn@C cable structures have rich SnO₂/C and Sn/SnO₂ heterointerfaces and the associated defects, which increase interfacial and defect-induced polarization losses, as visually demonstrated by off-axis electron holography. The development of the Sn@C cable structure represents a notable advancement in broadening the scope of materials with potential applications in stealth technology, and this study also contributes to the understanding of how heterojunctions can improve EMA performance.

Strain engineering on metal-based catalysts has been utilized as an efficacious strategy to regulate the mechanism and pathways in various electrocatalytic reactions. However, controlling strain and establishing the strain-activity relationship still remain significant challenges. Herein, three different and continuous tensile strains (CuPd-1.90%, CuAu-3.37%, and CuAg-4.33%) are successfully induced by introducing heteroatoms with different atomic radius. The catalytic performances of CuPd-1.90%, CuAu-3.37%, and CuAg-4.33% display a positive correlation against tensile strains in electrochemical CO₂ reduction reaction (CO₂RR). Specifically, CuAg-4.33% exhibits superior catalytic performance with a 77.9% Faradaic efficiency of multi-carbon products at –300 mA cm^–2 current density, significantly higher than those of pristine Cu (Cu-0%). Theoretical calculations and in situ spectroscopies verify that tensile strain can affect the d-band center of Cu, thereby altering the binding energy of *CO intermediates and Gibbs free energies of the C–C coupling procedure. This work might highlight a new method for precisely regulating the lattice strain of metallic catalysts in different electrocatalytic reactions.