Molten salt synthesis of KCl-preintercalated C3N4 nanosheets with abundant pyridinic-N as a superior anode with 10 K cycles in lithium ion battery

Highly Crystalline Poly(heptazine imide)-Based Carbonaceous Anodes for Ultralong Lifespan and Low-Temperature Sodium-Ion Batteries

Carbon nitrides with layered structures and scalable syntheses have emerged as potential anode choices for the commercialization of sodium-ion batteries. However, the low crystallinity of materials synthesized through traditional thermal condensation leads to insufficient conductivity and poor cycling stability, which significantly hamper their practical applications. Herein, a facile salt-covering method was proposed for the synthesis of highly ordered crystalline C3N4-based all-carbon nanocomposites. The sealing environment created by this strategy leads to the formation of poly(heptazine imide) (PHI), the crystalline phase of C3N4, with extended π-conjugation and a fully condensed nanosheet structure. Meanwhile, theoretical calculations reveal the high crystallinity of C3N4 significantly reduces the energy barrier for electron transition and enables the generation of efficient charge transfer channels at the heterogeneous interface between carbon and C3N4. Accordingly, such nanocomposites present ultrastable cycling performances over 5000 cycles, with a high reversible capacity of 245.1 mAh g-1 at 2 A g-1 delivered. More importantly, they also exhibit an outstanding low-temperature capacity of 196.6 mAh g-1 at -20 °C. This work offers opportunities for the energy storage use of C3N4 and provides some clues for developing long-life and high-capacity anodes operated under extreme conditions.

Mesoporous polyvalent Ni-Mn-Co-O composite nanowire arrays towards integrated anodes boosting high-properties lithium storage

Ternary transition metal oxides (TMOs) are potentially promising anode materials for lithium storage with high power and energy density. Designing appropriate electrode structures is an effective strategy to sufficiently exhibit the advantages of TMOs for lithium storage. Here, we present the synthetic process and electrochemical properties of carbon-coated mesoporous Ni-Mn-Co-O (NMCO) nanowire arrays (NWAs) grown on Ni foam as an integrated electrode for lithium-ion batteries (LIBs). The electrochemical measurements show that the carbon-coated NMCO integrated electrode exhibits high capacity and cycling properties. In addition, we have also developed an all one-dimensional (1D) structural full cell using an LiMn₂O₄ nanorod cathode and an NMCO/Ni NWAs@C-550 anode, which exhibits relatively outstanding cycling properties.

A Comprehensive Review on Graphitic Carbon Nitride for Carbon Dioxide Photoreduction

Inspired by natural photosynthesis, harnessing the wide range of natural solar energy and utilizing appropriate semiconductor-based catalysts to convert carbon dioxide into beneficial energy species, for example, CO, CH₄ , HCOOH, and CH₃ COH have been shown to be a sustainable and more environmentally friendly approach. Graphitic carbon nitride (g-C₃ N₄ ) has been regarded as a highly effective photocatalyst for the CO₂ reduction reaction, owing to its cost-effectiveness, high thermal and chemical stability, visible light absorption capability, and low toxicity. However, weaker electrical conductivity, fast recombination rate, smaller visible light absorption window, and reduced surface area make this catalytic material unsuitable for commercial photocatalytic applications. Therefore, certain procedures, including elemental doping, structural modulation, functional group adjustment of g-C₃ N₄ , the addition of metal complex motif, and others, may be used to improve its photocatalytic activity towards effective CO₂ reduction. This review has investigated the scientific community's perspectives on synthetic pathways and material optimization approaches used to increase the selectivity and efficiency of the g-C₃ N₄ -based hybrid structures, as well as their benefits and drawbacks on photocatalytic CO₂ reduction. Finally, the review concludes a comparative discussion and presents a promising picture of the future scope of the improvements.