通过光催化或光电化学(PEC)和氮还原反应(NRR)合成氨已成为该领域近期的研究热点之一。其中催化的材料和策略对NRR至关重要。在这里,制备了Ni掺杂的MoS2/Si纳米线(Ni-MoS2/SiNWs)光电阴极,其中通过金属辅助化学蚀刻方法在Si切片的表面上形成SiNWs,然后将水热合成的Ni-MoS2纳米片浇铸涂覆在SiNWs电极上。通过用亲水性牛血清白蛋白处理疏水性多孔配位聚合物用于随后的水分散来制备具有高N2溶解度的多孔水。相关电极和材料的特征在于电化学,紫外-可见分光光度法,扫描电子显微镜/能量色散光谱,透射电子显微镜,X射线衍射,X射线光电子能谱,Brunauer-Emmett-Teller方法,和zeta电位法。在最佳条件下,Ni-MoS2/SiNWs光电阴极和对PEC-NRR具有高氮溶解度的多孔水的使用可使NH3的产率为12.0mmolh-1m-2(例如,在0.25V对RHE时),并从光电极固有的无光电流光催化作用和PEC中三种电子的建议分类中讨论了高于100%的表观法拉第效率,这对理解和改进其他基于PEC的过程具有一定的参考价值。
The synthesis of ammonia through photocatalysis or photoelectrochemistry (PEC) and nitrogen reduction reaction (NRR) has become one of the recent research hotspots in the field, where the catalyzed materials and strategies are critical for the NRR. Herein, a Ni-doped MoS2/Si nanowires (Ni-MoS2/Si NWs) photocathode is prepared, where the Si NWs are formed on the surface of a Si slice by the metal-assisted chemical etching method, and the hydrothermally synthesized Ni-MoS2 nanosheets are then cast-coated on the Si NWs electrode. Porous water with high solubility of N2 is prepared by treating a hydrophobic porous coordination polymer with hydrophilic bovine serum albumin for subsequent aqueous dispersing. The relevant electrodes and materials are characterized by electrochemistry, UV-vis spectrophotometry, scanning electron microscopy/energy dispersive spectroscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller method, and zeta potential method. The uses of the Ni-MoS2/Si NWs photocathode and the porous water with high nitrogen solubility for PEC-NRR give a yield of NH3 of 12.0 mmol h-1 m-2 under optimal conditions (e.g., at 0.25 V vs RHE), and the obtained apparent Faradaic efficiency higher than 100% is discussed from the inherent photocurrent-free photocatalysis effect of the photoelectrodes and the suggested classification of three kinds of electrons in PEC, which may have some reference value in understanding and improving other PEC-based processes.