Narrow Results

In this work, carbon nitride (C₃N₄) nanoparticles (NPs) were synthesized by pulse laser ablation of graphite in ammonium solution, and deposited on silicon substrates by spray. Fourier transform infrared spectroscopy (FTIR), UV-visible spectrophotometer and transmission electron microscopy (TEM) were used to study bonding, absorption, size and morphology of the produce NPs. The FTIR absorption peaks at 2121.6, 1631.7 and 1384 cm^-1 stretching vibration bond, it is inferred for the C≡N, C=N and C–N, respectively. Bonds suggests the formation, C₃N₄ NPs. UV absorption peaks coincide with the electronic transitions corresponding to the formation, C₃N₄ NPs with 3.98 eV optical bandgap. The TEM show the aggregation of the C₃N₄ NPs with size ranges from 4 to 83 nm, and also the leaf-like structure are shown in the structure of C₃N₄ suspension. High performance rectifying C₃N₄/Si heterojunction with a rectifying ratio exceeding 345 at V = 5V was obtained, with high photoresponsivity of 2.33 A/W at 600 nm.The results show that C₃N₄ NPs on silicon substrates will act as very good candidates for making high efficiency photodiodes.

Electrocatalytic reduction of CO₂ into carbon-containing chemical product is greatly desired for mitigating the air pollution and energy crisis. However, there is great challenge to design highly active and stable electrocatalyst for the CO₂ reduction reaction (CO₂RR). Here, we develop a facile strategy of graphitic carbon nitride nanosheets-immobilized single-atom Zn (ZnSA–CN–G) to control the mitigation of electrocatalytic CO₂RR. The as-synthesized ZnSA–CN–G nanosheets not only possess abundant single-atom Zn as active sites, but also show unique architectures with high surface area and high electrical conductivity. Consequently, the ZnSA–CN–G nanosheets exhibit high electrocatalytic selectivity for CO₂RR, including a high Faradaic efficiency value of 87.1% for the production of CO at $-$0.5V versus RHE. Moreover, such simple approach can be further applied to synthesize a variety of other single-atom catalysts.

Herein, we have designed and synthesized a series of MnO_x/g-C₃N₄ composite photocatalysts via a one-step heat treatment method using a mixture of melamine and manganese acetate precursors. The as-prepared MnO_x/g-C₃N₄ composite photocatalysts show high photocatalytic H₂ production activity, and an optimal loading of 1.8wt.% MnO_x can enhance the H₂ production by approximately 2.7 times than that with pure g-C₃N₄. The high photocatalytic H₂-production activity can be attributed to the hole trapping and absorbing ability of the MnO_x cocatalyst, which can significantly inhibit the recombination rate of the photogenerated electrons and holes. This work not only shows a simple way to enhance the photocatalytic H₂-production activity of g-C₃N₄ but also demonstrates that MnO_x can be used as an efficient and low-cost cocatalyst for the photocatalytic production of H₂.