北京科技大学孙再成团队合成了一种可高效制氢的多合一光催化剂：Ga掺杂的聚合氮化碳。 相关研究成果于2021年1月20日发表在国际知名学术期刊《德国应用化学》。

光催化系统通常由催化剂和助催化剂构成，以实现光吸收、电子空穴分离和表面反应。开发一种功能齐全的单一光催化剂以降低效率损失是一个巨大的挑战。

该文中，研究人员将活性GaN₄位点整合到聚合碳氮化物（CN）光催化剂（GCN）中，无助催化剂的GCN的光催化产氢速率为9904 µmol h^-1 g^-1，分别是纯CN（61 µmol h^-1 g^-1）和含1.0 wt%Pt的CN（2981 µmol h^-1g^-1）的162倍和3.3倍。在光照下，电子被注入并储存在LUMO所在的GaN₄位点。HOMO分布在芳香环上导致空间电荷分离。瞬态光电压揭示了GCN的电子储存能力。负的GaN₄促进了质子在激发态的吸附。正的吸附能在电子传递到质子后驱动氢气从GaN4解吸。

研究工作为合理设计和探索新型制氢催化剂提供了途径。

附：英文原文

Title: All‐in‐one photocatalyst for high performance H2 production: Ga doped polymeric carbon nitride

Author: Wenshuai Jiang, Yajie Zhao, Xupeng Zong, Haodong Nie, Lijuan Niu, Li An, Dan Qu, Xiayan Wang, Zhenhui Kang, Zaicheng Sun

Issue&Volume: 20 January 2021

Abstract: A photocatalyst system is generally constructed by catalyst and cocatalyst to achieve light absorption, electron‐hole separation, and surface reaction. It is a great challenge to develop a sole photocatalyst with all functions to lower the efficiency loss. Here, we integrate the active GaN4   site into polymeric carbon nitride (CN)   photocatalyst (GCN), which displays an excellent H2   production rate of 9904  μmol h‐1  g‐1. It is 162 and 3.3 times higher than that of  CN  with the absence  ( 61  μmolh‐1  g‐1)  and presence ( 2981  μmolh‐1  g‐1) of 1.0 wt% Pt, respectively. Under light irradiation, the electron is injected and stored at the GaN4   site, where the LUMO locates. The HOMO distributes on the aromatic ring resulting in the spatial charge separation.  T ransient photovoltage discloses the electron storage capability of GCN. The negative GaN4   promotes the proton adsorption in the excited state. The positive adsorption energy drives the H2   desorption from GaN4   after passing the electron to the proton. Our work opens up opportunities for rational design and explores the novel catalyst for H2   production.

DOI: 10.1002/anie.202015779

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202015779