Unique PCoN Surface Bonding States Constructed on g‐C₃N₄ Nanosheets for Drastically Enhanced Photocatalytic Activity of H₂ Evolution

Abstract

Developing high‐efficiency and low‐cost photocatalysts by avoiding expensive noble metals, yet remarkably improving H2 evolution performance, is a great challenge. Noble‐metal‐free catalysts containing Co(Fe)NC moieties have been widely reported in recent years for electrochemical oxygen reduction reaction and have also gained noticeable interest for organic transformation. However, to date, no prior studies are available in the literature about the activity of N‐coordinated metal centers for photocatalytic H2 evolution. Herein, a new photocatalyst containing g‐C3N4 decorated with CoP nanodots constructed from low‐cost precursors is reported. It is for the first time revealed that the unique P(δ−)Co(δ+)N(δ−) surface bonding states lead to much superior H2 evolution activity (96.2 µmol h−1) compared to noble metal (Pt)‐decorated g‐C3N4 photocatalyst (32.3 µmol h−1). The quantum efficiency of 12.4% at 420 nm is also much higher than the record values (≈2%) of other transition metal cocatalysts‐loaded g‐C3N4. It is believed that this work marks an important step toward developing high‐performance and low‐cost photocatalytic materials for H2 evolution.

Phosphorus‐doped Isotype g‐C3N4/g‐C3N4: An Efficient Charge Transfer System for Photoelectrochemical Water Oxidation

“…In general, the PL emission of the semiconductors originates from the radiative recombination of free charge carriers . Hence, the observed PL quenching in P‐g‐C 3 N 4 is indicative of restrained recombination of photogenerated electrons and holes due to faster transfer of photoelectrons in n‐type carbon nitride . The suppressed carrier recombination of P‐g‐C 3 N 4 is then supported by shortened fluorescence lifetime calculated through simulating time‐resolved PL decay, shown in Figure b.…”

Hierarchical ZnIn2S4/MoSe2 Nanoarchitectures for Efficient Noble‐Metal‐Free Photocatalytic Hydrogen Evolution under Visible Light

“…As plotted in Figure 6a, pristine MoSe 2 evolves an egligible amount of H 2 .P ure ZnIn 2 S 4 features an extraordinary photocatalytic activity, giving aH 2 evolution rate of 1023 mmol g À1 h À1 ,w hich surpasses most of the previously reported pristineZ nIn 2 S 4 materials. [43][44][45] To evaluatet he photocatalytic stability of the nanocomposites, recycling experiments werep erformedo n the H 2 evolution activity of the ZnIn 2 S 4 /2 %MoSe 2 sample. The2 Du ltrathin ZnIn 2 S 4 nanosheets profoundly lower the charge-transfer resistance and shorten the diffusion pathway of charge carriers, thus facilitating fast and efficient separation of photo-induced charge carriers.…”

Photoassisted Construction of Holey Defective g‐C3N4 Photocatalysts for Efficient Visible‐Light‐Driven H2O2 Production

“…Bulk g‐C 3 N 4 (BCN) has limited visible‐light absorption ability and also suffers from a low separation efficiency of photoexcited charge carriers, resulting in low photocatalytic activity . Aiming at improving the photocatalytic performance of g‐C 3 N 4 , various strategies have been developed, such as heteroatoms doping, nanostructure design, dye sensitization, and coupling with other semiconductors or conductors . Particularly, the introduction of nitrogen defects into the g‐C 3 N 4 framework was recently developed as an effective strategy to significantly enhance the photocatalytic activity of g‐C 3 N 4 under visible light .…”