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Matching the thickness of the graphitic carbon nitride (CN) nanolayer with the charge diffusion length is expected to compensate for the poor intrinsic conductivity and charge recombination in CN for photoelectrochemical cells (PEC). Herein, the compact CN nanolayer with tunable thickness is in situ coated on carbon fibers. The compact packing along with good contact with the substrate improves the electron transport and alleviates the charge recombination. The PEC investigation shows CN nanolayer of 93 nm-thick yields an optimum photocurrent of 116 µA cm -2 at 1.23 V versus RHE, comparable to most micrometer-thick CN layers, with a low onset potential of 0.2 V in 1 m KOH under 1 sun illumination. This optimum performance suggests the electron diffusion length matches with the thickness of the CN nanolayer. Further deposition of NiFe-layered double hydroxide enhanced the surface water oxidation kinetics, delivering an improved photocurrent of 210 µA cm -2 with IPCE of 12.8% at 400 nm. The CN nanolayer also shows extended potential in PEC organic synthesis. This work experimentally reveals the PEC behavior of the nanometer-thick CN layer, providing new insights into CN in the application of energy and environment-related fields., (© 2024 Wiley‐VCH GmbH.)

The rapid charge recombination, low selectivity for two-electron oxygen reduction reaction (ORR), and limited O 2 diffusion rate hinder the practical applications of photocatalytic H 2 O 2 generation. Herein, a triphase photocatalytic system in which the H 2 O 2 generation occurs at the air-liquid-solid joint interfaces is developed, using polymeric carbon nitride (PCN). The introduction of pyrrole units and cyano group into PCN can promote the activation of oxygen molecules and facilitate the spatial separation of HOMO and LUMO orbits, hence improving the charge carrier separation efficiency and enhancing the formation of H 2 O 2 . Importantly, the gas-liquid-solid triphase interface system allows for the rapid transport of oxygen from the air to the reaction interface, overcoming the low solubility and slow diffusion of oxygen in the water in conventional liquid reaction systems. The triphase system shows a benchmark H 2 O 2 generation rate over PCN-based materials in pure water (2063.21 µmol g -1 h -1 ), which is an approximate tenfold enhancement as compared to powder photocatalyst (215.44 µmol g -1 h -1 ). Simulation and electrochemical tests reveal that the rapid oxygen diffusion rate of triphase interface can promote charge separation and provide more O 2 to generate H 2 O 2 . This work provides a promising strategy for constructing an efficient and sustainable H 2 O 2 production system., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

The construction of multi-heteroatom-doped metal-free carbon with a reversibly oxygen-involving electrocatalytic performance is highly desirable for rechargeable metal-air batteries. However, the conventional approach for doping heteroatoms into the carbon matrix remains a huge challenge owing to multistep postdoping procedures. Here, a self-templated carbonization strategy to prepare a nitrogen, phosphorus, and fluorine tri-doped carbon nanosphere (NPF-CNS) is developed, during which a heteroatom-enriched covalent triazine polymer serves as a "self-doping" precursor with C, N, P, and F elements simultaneously, avoiding the tedious and inefficient postdoping procedures. Introducing F enhances the electronic structure and surface wettability of the as-obtained catalyst, beneficial to improve the electrocatalytic performance. The optimized NPF-CNS catalyst exhibits a superb electrocatalytic oxygen reduction reaction (ORR) activity, long-term durability in pH-universal conditions as well as outstanding oxygen evolution reaction (OER) performance in an alkaline electrolyte. These superior ORR/OER bifunctional electrocatalytic activities are attributed to the predesigned heteroatom catalytic active sites and high specific surface areas of NPF-CNS. As a demonstration, a zinc-air battery using the NPF-CNS cathode displays a high peak power density of 144 mW cm -2 and great stability during 385 discharging/charging cycles, surpassing that of the commercial Pt/C catalyst., (© 2020 Wiley-VCH GmbH.)

Major challenges in developing 2D transition-metal disulfides (TMDs) as anode materials for lithium/sodium ion batteries (LIBs/SIBs) lie in rational design and targeted synthesis of TMD-based nanocomposite structures with precisely controlled ion and electron transport. Herein, a general and scalable solvent-exchange strategy is presented for uniform dispersion of few-layer MoS 2 (f-MoS 2 ) from high-boiling-point solvents (N-methyl-2-pyrrolidone (NMP), N,N-dimethyl formaldehyde (DMF), etc.) into low-boiling-point solvents (water, ethanol, etc.). The solvent-exchange strategy dramatically simplifies high-yield production of dispersible MoS 2 nanosheets as well as facilitates subsequent decoration of MoS 2 for various applications. As a demonstration, MoS 2 -decorated nitrogen-rich carbon spheres (MoS 2 -NCS) are prepared via in situ growth of polypyrrole and subsequent pyrolysis. Benefiting from its ultrathin feature, largely exposed active surface, highly conductive framework and excellent structural integrity, the 2D core-shell architecture of MoS 2 -NCS exhibits an outstanding reversible capacity and excellent cycling performance, achieving high initial discharge capacity of 1087.5 and 508.6 mA h g -1 at 0.1 A g -1 , capacity retentions of 95.6% and 94.2% after 500 and 250 charge/discharge cycles at 1 A g -1 , for lithium/sodium ion storages, respectively., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Direct hydrogenation of C=C double bonds is a basic transformation in organic chemistry which is vanishing from simple practice because of the need for pressurized hydrogen. Ammonia borane (AB) has emerged as a hydrogen source through its safety and high hydrogen content. However, in conventional systems the hydrogen liberated from the high-cost AB cannot be fully utilized. Herein, we develop a novel Pd/g-C 3 N 4 stabilized Pickering emulsion microreactor, in which alkenes are hydrogenated in the oil phase with hydrogen originating from AB in the water phase, catalysed by the Pd nanoparticles at the interfaces. This approach is advantageous for more economical hydrogen utilization over conventional systems. The emulsion microreactor can be applied to a range of alkene substrates, with the conversion rates achieving >95 % by a simple modification., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new and simple synthetic route is introduced to covalently functionalize the carbon nitride (CN) framework by the implementation of halogenated phenyl groups (Cl, Br and I), which serve as a chemically reactive center, within the CN framework. The covalent modification is demonstrated here by substituting phenyl and tert-butyl propionate onto the modified-CN framework through Suzuki and reductive-Heck cross-coupling reactions, respectively. The effective functionalization leads to a facile exfoliation of the CN framework into thinner layers and greatly enhances the dispersibility in many solvents as well as the photocatalytic activity compared to the unmodified CN. The general covalent modification opens the possibility for tailor-made design of dispersible CN materials, including their photophysical and chemical properties, toward their exploitation in many fields, such as photocatalysis, bio-imaging, sensing, and heterogeneous catalysis., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Graphitic carbon nitride (CN) has been widely regarded as a promising photocatalyst since the discovery of its capability for photocatalytic hydrogen evolution. Herein, we developed a functional CN film on a conductive fluorine-doped tin oxide (FTO) electrode by using a microprinting-based direct growth method. Furthermore, the photoelectrochemical performance of the derived CN@FTO film was demonstrated to be enhanced by incorporating molecular cobalt species. The reduced charge transport resistance in the cobalt-modified CN@FTO films is suggested to accelerate the charge-carrier transfer rate and thus to improve the performance in photoelectrochemical application. The approach is versatile and can be further optimized by selecting a proper "ink" solution and modifier on various conductive substrates., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

g-C 3 N 4 has been found to be highly functional in many fields, such as photocatalysis, electrocatalysis, and chemical analysis. Pickering emulsion polymerization is a fascinating strategy to fabricate a range of nanomaterials, in which the emulsion is stabilized by solid particles, rather than molecular surfactants. Herein, we demonstrate that g-C 3 N 4 can act as a remarkable stabilizer for Pickering emulsion polymerization. Contrary to normal Pickering systems, monodisperse polystyrene microspheres with tunable size, surface charge, and morphology were achieved using this approach. Importantly, the g-C 3 N 4 hybridized latex is highly processable and has exhibited multiple functions: manufacture of photonic crystals via self-organization, stabilizing Pickering emulsion owing to proper wettability, and acting as bioimaging agents with enriched fluorescent colors. Considering the easy synthesis and low cost of g-C 3 N 4 , our approach has a high potential for scale-up synthesis and practical translation., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Shape and nanostructure control has great potential to enable graphitic carbon nitride (C 3 N 4 ) structures with new properties and functionalities. In this work, a new type of hierarchically structured nanoporous C 3 N 4 is introduced. The C 3 N 4 exhibits unique, edelweiss-like morphology, with components ranging from millimeter-sized bunches to subnanometer-thick layers. A one-step vapor-solid deposition approach using supramolecular aggregates as the precursor is carried out to accomplish the growth. Supramolecular pre-association plays a crucial role in achieving this nanostructure by directing the vaporization and deposition processes. Furthermore, very small C 3 N 4 quantum dots can be readily acquired by bath sonication of the thin layers in water. The supramolecular preorganization growth strategy developed herein may provide a general methodology in the design of advanced photoelectric materials with broad applications in energy conversion and storage., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Carbon nitride (g-CN) has attracted significant interest in the last years as a robust, low-cost alternative to metal-based materials in different fields due to its low price, environmentally benign character, simple synthesis and tunable properties. In particular, g-CN demonstrates promising activity in energy-related applications such as photo and heterogeneous catalysis, batteries and electrolysis. However, while g-CN is already well-established as a photocatalyst, its utilization in (opto)electronic devices is still at an early stage. This Focus Review concentrates on the utilization of g-CN in solar and photoelectrochemical cells, electrolyzers and light emitting diode alongside the recap of new synthetic approaches. This review is expected to provide useful insights into the design and fabrication of g-CN based photoelectronic devices as well as g-CN working principles, including the main challenges toward its integration in optoelectronic devices., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An unusual small molecule, dithiooxamide is used to produce nanostructured carbon via direct pyrolysis. The carbon shows a unique 2D-layer assembled structure and is in situ dual-heteroatom (N and S)-doped, meanwhile having relatively high surface area. These carbon materials can be further decorated with inorganic parts via a precomplexing approach. The functionalized carbon and the hybrid nanomaterials demonstrate remarkable performance for lithium-ion storage., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel type of quantum dot (Ph-CN) is manufactured from graphitic carbon nitride by "lining" the carbon nitride structure with phenyl groups through supramolecular preorganization. This approach requires no chemical etching or hydrothermal treatments like other competing nanoparticle syntheses and is easy and safe to use. The Ph-CN nanoparticles exhibit bright, tunable fluorescence, with a high quantum yield of 48.4 % in aqueous colloidal suspensions. Interestingly, the observed Stokes shift of approximately 200 nm is higher than the maximum values reported for carbon nitride based fluorophores. The high quantum yield and the large Stokes shift are related to the structural surface organization of the phenyl groups, which affects the π-electron delocalization in the conjugated carbon nitride networks and induces colloidal stability. The remarkable performance of the Ph-CN nanoparticles in imaging is demonstrated by a simple incubation study with HeLa cells., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Herein, we show the facile synthesis of an efficient silver phosphate/graphitic carbon nitride (Ag3 PO4 /g-C3 N4 ) photocatalyst for oxygen production and pollutant degradation by using electrostatically driven assembly and ion-exchange processes. The composite materials demonstrate a sheet-like C3 N4 structure, decorated with different Ag3 PO4 particles sizes. Detailed analysis of the reactions mechanism by electron-spin resonance and radical-capture agents strongly imply the formation of an in situ Z-scheme by the evolution of small silver nanoparticles in the interface of the materials under illumination. The Ag nanoparticles improve charge separation within the composite material by acting as a storage and recombination center for electrons and holes from Ag3 PO4 and C3 N4 , respectively. In addition, the photostability of Ag3 PO4 is enhanced relative to that of the bulk materials, which results in a stabilized heterojunction. We believe that this work provides new insight into the operation mechanism of composite photocatalysts for water splitting and opens the possibility for advanced photocatalysis based on the higher oxidation power of Ag3 PO4 ., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)