A Cu-doped two-dimensional material-based heterojunction photoelectrode: application for highly sensitive photoelectrochemical detection of hydrogen sulfide.

In this work, on the basis of a Cu-doped two-dimensional material-based heterojunction photoelectrode, a novel anodic photoelectrochemical (PEC) sensing platform was constructed for highly sensitive detection of endogenous HS. Briefly, with g-CN and TiO as representative materials, the sensor was fabricated by modifying g-CN/TiO nanorod arrays (NAs) onto the surface of fluorine-doped tin oxide (FTO) and then doping Cu as a Cu S ( = 1, 2) precursor. After the binding of S with surface-attached Cu, the signal was quenched owing to the generation of Cu S which offers trapping sites to hinder generation of photocurrent signals. Since the photocurrent inhibition was intimately associated with the concentration of S, a highly sensitive PEC biosensor was fabricated for HS detection. More importantly, the proposed sensing platform showed the enormous potential of g-CN/TiO NAs for further development of PEC bioanalysis, which may serve as a common basis for other semiconductor applications and stimulates the exploration of numerous high-performance nanocomposites.