Mo-doped BiVO4 has emerged as a promising material for photoelectrodes for photoelectrochemical water splitting, however, still shows a limited efficiency for light-driven water oxidation. We present the influence of an oxygen-evolution catalyst composed of Ni, Fe, and Cr oxides on the activity of Mo:BiVO4 photoanodes. The photoanodes are prepared by spray-coating, enabling compositional and thickness gradients of the incorporated catalyst. Two different configurations are evaluated, namely with the catalyst embedded into the Mo:BiVO4 film or deposited on top of it. Both configurations provide a significantly different impact on the photoelectrocatalytic efficiency. Structural characterisation of the materials by means of SEM, TEM and XRD as well as the photoelectrocatalytic activity investigated by means of an optical scanning droplet cell and in situ detection of oxygen using scanning photoelectrochemical microscopy are presented.

中文翻译：

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通过含镍，铁和氧化铬的复合催化剂调节掺钼的BiVO4的光驱动水氧化效率。

掺杂Mo的BiVO4已成为一种有前途的光电化学分解水用电极材料，但光驱动水氧化的效率仍然有限。我们介绍了由Ni，Fe和Cr氧化物组成的放氧催化剂对Mo：BiVO4光阳极活性的影响。光阳极通过喷涂制备，从而使引入的催化剂具有成分和厚度梯度。评价了两种不同的构型，即催化剂嵌入Mo：BiVO4膜中或沉积在其顶部。两种配置都对光电催化效率产生了明显不同的影响。通过SEM对材料进行结构表征，