Enhancement of photoelectrochemical activity of Fe2O3 nanowires decorated with carbon quantum dots

Owing to its up-conversion photoluminescence, photo-induced electron transfer property, and excellent conductivity, carbon quantum dots (CQDs) have been established as effective sensitizers in combination with Fe₂O₃ nanowires for enhancing the catalytic activity of photoelectrochemical water oxidation. In comparison to pristine Fe₂O₃ nanowires, Fe₂O₃ nanowires decorated with CQDs demonstrate 27 orders of magnitude increase in photocurrent density at 0.23 V vs. Ag/AgCl. The mechanism of enhanced photoelectrochemical activity of CQDs/Fe₂O₃ composite was also investigated. Thereby, it is confirmed that the enhanced optical absorption, accelerated interfacial charge carrier transfer and effective separation of photogenerated electron-hole pairs induced by CQDs decoration account for the enhancement of CQDs/Fe₂O₃ nanowire arrays in photoelectrochemical application.