Hao Yuchen, Dong Xiaoli, Zhai Shangru, Ma Hongchao, Wang Xiuying, Zhang Xiufang
School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian, 116034, P. R. China.
Chemistry. 2016 Dec 23;22(52):18722-18728. doi: 10.1002/chem.201604510. Epub 2016 Nov 16.
Sunlight-driven dinitrogen fixation can lead to a novel concept for the production of ammonia under mild conditions. However, the efficient artificial photosynthesis of ammonia from ordinary air (instead of high pure N ) has never been implemented. Here, we report for the first time the intrinsic catalytic activity of Bi MoO catalyst for direct ammonia synthesis under light irradiation. The edge-exposed coordinatively unsaturated Mo atoms in an Mo-O coordination polyhedron can act as activation centers to achieve the chemisorption, activation, and photoreduction of dinitrogen efficiently. Using that insight as a starting point, through rational structure and defect engineering, the optimized Bi MoO sunlight-driven nitrogen fixation system, which simultaneously possesses robust nitrogen activation ability, excellent light-harvesting performance, and efficient charge transmission was successfully constructed. As a surprising achievement, this photocatalytic system demonstrated for the first time ultra-efficient (1.3 mmol g h ) and stable sunlight-driven nitrogen fixation from air in the absence of any organic scavengers.
阳光驱动的固氮作用可为温和条件下氨的生产带来一个全新概念。然而，利用普通空气（而非高纯氮气）进行高效的氨人工光合作用尚未实现。在此，我们首次报道了Bi₂MoO₆催化剂在光照下直接合成氨的本征催化活性。Mo-O配位多面体中边缘暴露的配位不饱和Mo原子可作为活化中心，从而高效实现二氮的化学吸附、活化及光还原。基于这一认识，通过合理的结构与缺陷工程，成功构建了优化的Bi₂MoO₆阳光驱动固氮体系，该体系同时具备强大的氮活化能力、优异的光捕获性能及高效的电荷传输能力。一项令人惊喜的成果是，该光催化体系首次在无任何有机清除剂的情况下，展示了超高效（1.3 mmol g⁻¹ h⁻¹）且稳定的空气中阳光驱动固氮作用。
