Singlet oxygen (1O2) is an excellent active species for the selective degradation of organic pollutions. However, it is difficult to achieve high efficiency and selectivity for the generation of 1O2. In this work, we develop a graphitic carbon nitride supported Fe single‐atoms catalyst (Fe1/CN) containing highly uniform Fe‐N4 active sites with a high Fe loading of 11.2 wt %. The Fe1/CN achieves generation of 100 % 1O2 by activating peroxymonosulfate (PMS), which shows an ultrahigh p‐chlorophenol degradation efficiency. Density functional theory calculations results demonstrate that in contrast to Co and Ni single‐atom sites, the Fe‐N4 sites in Fe1/CN adsorb the terminal O of PMS, which can facilitate the oxidization of PMS to form SO5.−, and thereafter efficiently generate 1O2 with 100 % selectivity. In addition, the Fe1/CN exhibits strong resistance to inorganic ions, natural organic matter, and pH value during the degradation of organic pollutants in the presence of PMS. This work develops a novel catalyst for the 100 % selective production of 1O2 for highly selective and efficient degradation of pollutants.

Single atom catalysts (SACs) with the maximized metal atom efficiency have sparked great attention. However, it is challenging to obtain SACs with high metal loading, high catalytic activity, and good stability. Herein, we demonstrate a new strategy to develop a highly active and stable Ag single atom in carbon nitride (Ag‐N2C2/CN) catalyst with a unique coordination. The Ag atomic dispersion and Ag‐N2C2 configuration have been identified by aberration‐correction high‐angle‐annular‐dark‐field scanning transmission electron microscopy (AC‐HAADF‐STEM) and extended X‐ray absorption. Experiments and DFT calculations further verify that Ag‐N2C2 can reduce the H2 evolution barrier, expand the light absorption range, and improve the charge transfer of CN. As a result, the Ag‐N2C2/CN catalyst exhibits much better H2 evolution activity than the N‐coordinated Ag single atom in CN (Ag‐N4/CN), and is even superior to the Pt nanoparticle‐loaded CN (PtNP/CN). This work provides a new idea for the design and synthesis of SACs with novel configurations and excellent catalytic activity and durability.

Au nanorods (NRs) decorated carbon nitride nanotubes (Au NRs/CNNTs) photocatalysts have been designed and prepared by impregnation-annealing approach. Localized surface plasmon resonance (LSPR) peaks of Au NRs can be adjusted by changing the aspect ratios, and the light absorption range of Au NRs/CNNTs is extended to longer wavelength even near-infrared light. Optimal composition of Pt@Au NR 769 /CNNT 650 has been achieved by adjusting the LSPR peaks of Au NRs and further depositing Pt nanoparticles (NPs), and the photocatalytic H 2 evolution rate is 207.0 µmol h −1 (20 mg catalyst). Preliminary LSPR enhancement photocatalytic mechanism is suggested. On one hand, LSPR of Au NRs is beneficial for visible-light utilization. On the other hand, Pt NPs and Au NRs have a synergetic enhancement effect on photocatalytic H 2 evolution of CNNTs, in which the local electromagnetic field can improve the photogenerated carrier separation and direct electron transfer increases the hot electron concentration while Au NRs as the electron channel can well restrain charge recombination, finally Pt as co-catalyst can boost H + reduction rate. This work provides a new way to develop efficient photocatalysts for splitting water, which can simultaneously extend light absorption range and facilitate carrier generation, transportation and reduce carrier recombination.