Iodine‐Manipulated Pt Single Atoms Bridged between Graphitic C <sub>3</sub> N <sub>4</sub> Nanosheets for Boosted Photocatalytic Hydrogen Evolution
Jiachao Shen, Chenghui Luo, Jianbin Liu, Kaixing Fu, Jili Yuan, Haifang Tang, Huiling Liu, Hao Zhang, Chengbin Liu
Abstract
Abstract The platinum (Pt) single‐atom site represents the limit of atomic utilization in Pt catalysis. In alkaline hydrogen evolution reaction (HER), slow water dissociation (Volmer step) and subsequent strong interactions between Pt and H atoms reduce the efficiency of H 2 desorption, resulting in an overall inefficient hydrogen evolution reaction. Addressing how to adjust the electronic structure of the Pt single‐atom site to further enhance the catalytic efficiency remains a significant scientific challenge. Herein, a Pt single‐atom photocatalysts with the Pt atoms confined within the interlayer of iodine (I)‐doped graphitic carbon nitride (g‐C 3 N 4 ) has been fabricated by a ball‐milling combined with a calcination strategy. Experiments and theoretical calculations demonstrate that interlayer single‐atom Pt enables photoinduced electrons to shuttle through layers, resulting in fast interlayer charge transfer, the I‐atom doping can enhance the light absorption capacity and electrical conductivity of the materials. Furthermore, the introduction of the I atoms increases the oxidation state of the Pt singe atoms between the g‐C 3 N 4 layers, promoting the dissociation of water, and the electronic state of the interaction between the I atom and the Pt atom is also conducive to H 2 desorption. Therefore, the proposed photocatalyst system provides exceptional photocatalytic alkaline HER performance. The hydrogen production rate at the stationary point is as high as 18.71 mmol g −1 h −1 , and the apparent quantum yield at 420 nm is 36.93%. Notably, the hydrogen production rate in seawater remains high at 10.66 mmol g −1 h −1 .