Zhang Tingfeng, Liu Ping, Wang Lili, Wang Shuai, Shi Jinsheng, Lan Xuefang
Department of Chemistry and Pharmacy, Qingdao Agricultural University, Qingdao 266000, China.
Chengyang Branch of Qingdao Ecological Environment Bureau, Qingdao 266000, China.
Materials (Basel). 2021 May 28;14(11):2894. doi: 10.3390/ma14112894.
A magnetically recyclable Ni/NiO/g-CN photocatalyst with significantly enhanced H2 evolution efficiency was successfully synthesized by a simple ethanol-solvothermal treatment. The presence of electronegative g-CN is found to be the key factor for Ni formation in ternary Ni/NiO/g-CN, which provides anchoring sites for Ni absorption and assembling sites for Ni nanoparticle formation. The metallic Ni, on one side, could act as an electron acceptor enhancing carrier separation and transfer efficiency, and on the other side, it could act as active sites for H evolution. The NiO forms a p-n heterojunction with g-CN, which also promotes carrier separation and transfer efficiency. The strong magnetic property of Ni/NiO/g-CN allows a good recyclability of catalyst from aqueous solution. The optimal Ni/NiO/g-CN showed a full-spectrum efficiency of 2310 μmol·h·g for hydrogen evolution, which is 210 times higher than that of pure g-CN. This ethanol solvothermal strategy provides a facile and low-cost synthesis of metal/metal oxide/g-CN for large-scale application.
通过简单的乙醇溶剂热法成功合成了一种具有显著提高的析氢效率且可磁回收的Ni/NiO/g-CN光催化剂。发现电负性的g-CN的存在是三元Ni/NiO/g-CN中Ni形成的关键因素，它为Ni的吸附提供了锚定位点，并为Ni纳米颗粒的形成提供了组装位点。一方面，金属Ni可以作为电子受体提高载流子分离和转移效率，另一方面，它可以作为析氢的活性位点。NiO与g-CN形成p-n异质结，这也促进了载流子分离和转移效率。Ni/NiO/g-CN的强磁性使得催化剂在水溶液中具有良好的可回收性。最佳的Ni/NiO/g-CN析氢全光谱效率为2310 μmol·h·g，比纯g-CN高210倍。这种乙醇溶剂热策略为大规模应用提供了一种简便且低成本的金属/金属氧化物/g-CN合成方法。
