Polydopamine inspired dual-functional templates to prepare photoanode with enhanced photoelectrochemical activity

Abstract In this work, we propose polydopamine inspired dual-functional template in the form of microspheres to prepare the TiO2 photoanode for a photocatalytic fuel cell. This new type template can not only ensure easy control of porous structure, which enhances mass transport and light scattering, but also enable nitrogen doping into TiO2 for visible-light response, which increases solar utilization. Because of these merits, the photoanode prepared by using this polydopamine inspired dual-functional template yields better photoelectrochemical activity. The newly-developed photoanode is also evaluated by incorporating it into a photocatalytic fuel cell in terms of electricity generation. Experimental results further confirm that the photocatalytic fuel cell with the photoanode prepared by using the polydopamine microspheres shows superior performance than does the one with conventional TiO2 photoanode. Effects of the size of polydopamine microspheres and its ratio to TiO2 are also studied. It is shown that the photoanode prepared by using 220-nm polydopamine microspheres at a ratio of 1:5 exhibits optimal performance. This study provides a new route to prepare high-performance photoanode.