Electrocatalytic hydrogen peroxide (H₂O₂) production via the two-electron oxygen reduction reaction is a promising alternative to the energy-intensive and high-pollution anthraquinone oxidation process. However, developing advanced electrocatalysts with high H₂O₂ yield, selectivity, and durability is still challenging, because of the limited quantity and easy passivation of active sites on typical metal-containing catalysts, especially for the state-of-the-art single-atom ones. To address this, we report a graphene/mesoporous carbon composite for high-rate and high-efficiency 2e⁻ oxygen reduction catalysis. The coordination of pyrrolic-N sites -modulates the adsorption configuration of the *OOH species to provide a kinetically favorable pathway for H₂O₂ production. Consequently, the H₂O₂ yield approaches 30 mol g⁻¹ h⁻¹ with a Faradaic efficiency of 80% and excellent durability, yielding a high H₂O₂ concentration of 7.2 g L⁻¹. This strategy of manipulating the adsorption configuration of reactants with multiple non-metal active sites provides a strategy to design efficient and durable metal-free electrocatalyst for 2e⁻ oxygen reduction.

Photoelectrochemical (PEC) water splitting is recognized as a sustainable strategy for hydrogen generation due to its abundant hydrogen source, utilization of inexhaustible solar energy, high‐purity product, and environment‐friendly process. To actualize a practical PEC water splitting, it is paramount to develop efficient, stable, safe, and low‐cost photoelectrode materials. Recently, graphitic carbon nitride (g‐C₃N₄) has aroused a great interest in the new generation photoelectrode materials because of its unique features, such as suitable band structure for water splitting, a certain range of visible light absorption, nontoxicity, and good stability. Some inherent defects of g‐C₃N₄, however, seriously impair further improvement on PEC performance, including low electronic conductivity, high recombination rate of photogenerated charges, and limited visible light absorption at long wavelength range. Construction of g‐C₃N₄‐based nanosized heteroarrays as photoelectrodes has been regarded as a promising strategy to circumvent these inherent limitations and achieve the high‐performance PEC water splitting due to the accelerated exciton separation and the reduced combination of photogenerated electrons/holes. Herein, we summarize in detail the latest progress of g‐C₃N₄‐based nanosized heteroarrays in PEC water‐splitting photoelectrodes. Firstly, the unique advantages of this type of photoelectrodes, including the highly ordered nanoarray architectures and the heterojunctions, are highlighted. Then, different g‐C₃N₄‐based nanosized heteroarrays are comprehensively discussed, in terms of their fabrication methods, PEC capacities, and mechanisms, etc. To conclude, the key challenges and possible solutions for future development on g‐C₃N₄‐based nanosized heteroarray photoelectrodes are discussed.

As a clean and renewable energy source, solar energy is a competitive alternative to replace conventional fossil fuels. Nevertheless, its serious fluctuating nature usually leads to a poor alignment with the actual energy demand. To solve this problem, the direct solar‐to‐electrochemical energy conversion and storage have been regarded as a feasible strategy. In this context, the development of high‐performance integrated devices based on solar energy conversion parts (i.e., solar cells or photoelectrodes) and electrochemical energy storage units (i.e., rechargeable batteries or supercapacitors [SCs]) has become increasingly necessary and urgent, in which carbon and carbon‐based functional materials play a fundamental role in determining their energy conversion/storage performances. Herein, we summarize the latest progress on these integrated devices for solar electricity energy conversion and storage, with special emphasis on the critical role of carbon‐based functional materials. First, principles of integrated devices are introduced, especially roles of carbon‐based materials in these hybrid energy devices. Then, two major types of important integrated devices, including photovoltaic and photoelectrochemical‐rechargeable batteries or SCs, are discussed in detail. Finally, key challenges and opportunities in the future development are also discussed. By this review, we hope to pave an avenue toward the development of stable and efficient devices for solar energy conversion and storage.

Due to the limitations of the raw materials and processes involved, polyolefin separators used in commercial lithium‐ion batteries (LIBs) have gradually failed to meet the increasing requirements of high‐end batteries in terms of energy density, power density, and safety. Hence, it is very important to develop next‐generation separators for advanced lithium (Li)‐based rechargeable batteries including LIBs and Li–S batteries. Nonwoven nanofiber membranes fabricated via electrospinning technology are highly attractive candidates for high‐end separators due to their simple processes, low‐cost equipment, controllable microporous structure, wide material applicability, and availability of multiple functions. In this review, the electrospinning technologies for separators are reviewed in terms of devices, process and environment, and polymer solution systems. Furthermore, strategies toward the improvement of electrospun separators in advanced LIBs and Li–S batteries are presented in terms of the compositions and the structure of nanofibers and separators. Finally, the challenges and prospects of electrospun separators in both academia and industry are proposed. We anticipate that these systematic discussions can provide information in terms of commercial applications of electrospun separators and offer new perspectives for the design of functional electrospun separators for advanced Li‐based batteries.

Self-assembling Au mesoflower arrays are prepared using a polymethylmethacrylate (PMMA) template on an iron substrate via a combined top-down/bottom-up nanofabrication strategy. The PMMA template with the holes around 300-500 nm in diameter is first fabricated by using polymer blend lithography on iron substrates, and the highly homogeneous Au mesoflower arrays with less than 10 nm intraparticle gaps are subsequently obtained by an in situ galvanic reaction between HAuCl4 solution and the iron substrate under optimal stirring of the solution as well as reaction time. Owing to the unique mesostructures and uniformity, Raman measurements show that the gold mesoflower arrays obtained demonstrated a strong and reproducible surface enhanced Raman scattering (SERS) enhancement on the order of ∼10(7)-10(8). The development of a SERS substrate based on the Au mesoflowers with high spatial density of hot spots, relatively low cost and facial synthesis provides a novel strategy for applications in chemical and biomolecular sensing.

Carbon nitride, an emerging polymeric semiconductor, has attracted attention in research ranging from photocatalysis to photodetection due to its favorable visible light response and high physicochemical stability. For its practical device application, the fabrication of high‐quality carbon nitride films on substrates is essential. However, conventional methodologies to achieve high polymerization of carbon nitride are often accompanied by its decomposition, significantly compromising the film quality. Herein, we report an ultrafast fabrication of carbon nitride film by laser direct writing (LDW). The instantaneous high temperature and pressure during LDW can efficiently boost the polymerization of carbon nitride and suppress its decomposition, resulting in high‐quality carbon nitride film with excellent mechanical stability with the substrate. Due to the efficient photon‐to‐electron conversion, it exhibits an outstanding photoelectrochemical water splitting and optoelectronic detection capability, even under strong acid/alkaline conditions. This study thus offers a facile and efficient LDW strategy for the rapid fabrication of carbon nitride film photoelectrodes, demonstrating its great feasibility in multifunctional photoelectrical applications, including but not limited to photoelectrochemical water splitting and optoelectronic detection.