A Cu(2+)-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(2+)-doped two-dimensional material-based heterojunction photoelectrode, a novel anodic photoelectrochemical (PEC) sensing platform was constructed for highly sensitive detection of endogenous H(2)S. Briefly, with g-C(3)N(4) and TiO(2) as representative materials, the sensor was fabricated by modifying g-C(3)N(4)/TiO(2) nanorod arrays (NAs) onto the surface of fluorine-doped tin oxide (FTO) and then doping Cu(2+) as a Cu(x)S (x = 1, 2) precursor. After the binding of S(2−) with surface-attached Cu(2+), the signal was quenched owing to the in situ generation of Cu(x)S which offers trapping sites to hinder generation of photocurrent signals. Since the photocurrent inhibition was intimately associated with the concentration of S(2−), a highly sensitive PEC biosensor was fabricated for H(2)S detection. More importantly, the proposed sensing platform showed the enormous potential of g-C(3)N(4)/TiO(2) 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.