Wang Junfeng, Zhao Chunran, Yuan Shude, Li Xiaojing, Zhang Jiayu, Hu Xin, Lin Hongjun, Wu Ying, He Yiming
Department of Materials Science and Engineering, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China.
Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China.
J Colloid Interface Sci. 2023 May 15;638:427-438. doi: 10.1016/j.jcis.2023.02.005. Epub 2023 Feb 4.
This study enhances the photocatalytic N immobilization performance of BiMoO through Cu doping. Cu-doped BiMoO was synthesized via a simple solvothermal method. Various characterizations were implemented to examine the influence of Cu doping on the properties of BiMoO. Results indicated that the doped Cu element had a valence state of + 2 and substituted the position of Bi. Cu doping exerted minimal effect on the morphology of BiMoO but largely influenced the energy band structure. The band gap was slightly narrowed, and the conduction band was raised, such that Cu-doped BiMoO could generate more electrons with stronger reducibility. Moreover, importantly, Cu doping reduced work function and improved charge separation efficiency, which was considered the major cause of enhanced photoactivity. In addition, the Cu-BiMoO catalyst exhibited higher capability in the adsorption and activation of N. Under the combined effects of the aforementioned changes, Cu-BiMoO demonstrated considerably higher photocatalytic efficiency than BiMoO. The optimized NH generation rate reached 302 μmol/L gh and 157 μmol/L gh under simulated solar light and visible light, respectively, both achieving about 2.2 times higher than that of BiMoO. This work provides a successful example of improving photocatalytic N fixation, and it may show some light on the design and preparation of heteroatom-doped semiconductor photocatalysts for N-to-NH conversion.
本研究通过铜掺杂提高了钼酸铋的光催化固氮性能。采用简单的溶剂热法合成了铜掺杂的钼酸铋。通过各种表征手段研究了铜掺杂对钼酸铋性能的影响。结果表明，掺杂的铜元素价态为 +2，取代了铋的位置。铜掺杂对钼酸铋的形貌影响极小，但对其能带结构有很大影响。带隙略有变窄，导带升高，使得铜掺杂的钼酸铋能够产生更多具有更强还原性的电子。此外，重要的是，铜掺杂降低了功函数，提高了电荷分离效率，这被认为是光活性增强的主要原因。另外，铜 - 钼酸铋催化剂在氮的吸附和活化方面表现出更高的能力。在上述变化的综合作用下，铜 - 钼酸铋的光催化效率比钼酸铋高得多。在模拟太阳光和可见光下，优化后的氨生成速率分别达到 302 μmol/L·g·h 和 157 μmol/L·g·h，均比钼酸铋高出约 2.2 倍。这项工作为提高光催化固氮提供了一个成功的例子，可能为氮转化为氨的杂原子掺杂半导体光催化剂的设计和制备提供一些启示。
