Visible-Light Induced Self-Powered Sensing Platform Based on a Photofuel Cell.

A self-powered sensing system possesses the capacity of harvesting energy from the environment and has no requirement for external electrical power supply during the chemical sensing of analytes. Herein, we design an enzyme-free self-powered sensing platform based on a photofuel cell (PFC) driven by visible-light, using glucose as a model analyte. The fabricated PFC consists of a Ni(OH)2/CdS/TiO2 photoanode and a hemin-graphene (HG) nanocomposite coated cathode in separated chambers. Under visible-light irradiation, glucose in the anodic chamber is facilely oxidized on Ni(OH)2/CdS/TiO2 while H2O2 in the cathodic chamber is catalytically reduced by HG, which generates a certain cell output sensitive to the variation of glucose concentration. Thus, a PFC based self-powered sensor is realized for glucose detection. Compared to the existing enzymatic self-powered glucose sensors, our proposed PFC based strategy exhibits much lower detection concentration. Moreover, it avoids the limitation of conventional enzyme immobilized electrodes and has the potential to develop high-performance self-powered sensors with broader analyte species.