Author: Yuxin Liu (Chongqing University) - In photocatalytic fuel cells, the photoanode serves as a pivotal component, governing the efficiency of light harvesting, charge separation, and the crucial oxidation reactions. However, the practical performance is greatly limited by slow reaction kinetics and poor interfacial mass transfer. Thus, in this work, a photocatalytic fuel cell with a 3D flow-through photoanode was constructed. Distinct from traditional flow-by configurations, this 3D structure features integrated microfluidic channels designed to actively direct the reactant flow through the porous photoanode material itself. This flow-through mode offers a fundamental advantage over the conventional flow-by mode: it dramatically reduces the thickness of diffusion boundary layer. Consequently, the mass transfer within the photoanode is substantially enhanced, resulting in a demonstrable boost in both the power generation and the pollutant degradation efficiency of the PFC (Fig.1). Additionally, the effects of reactant flow rate on cell performance were further investigated. The results show that the performance of the photocatalytic fuel cell was decreased reactant flow rate. Increased reactant flow rate leads to decreased residence time of the reactant on the photoanode surface and reduced contact time between the reactant and carrier.
