Rapid fabrication of oxygen defective α-Fe<sub>2</sub>O<sub>3</sub>(110) for enhanced photoelectrochemical activities
Mohamad Firdaus Mohamad Noh, Habib Ullah, Nurul Affiqah Arzaee, Azhar Ab Halim, Muhammad Amir Faizal Abdul Rahim, Nurul Aida Mohamed, Javad Safaei, Siti Nur Farhana Mohd Nasir, Guoxiu Wang, Mohd Asri Mat Teridi
Abstract
with the dominant (110) crystal plane is developed in a very short timescale of 10 minutes by employing aerosol-assisted chemical vapor deposition and pure nitrogen as a gas carrier. The oxygen-defective film exhibits almost 8 times higher photocurrent density compared to a hematite photoanode with a low concentration of oxygen vacancies which is prepared in purified air. The existence of oxygen vacancies improves light absorption ability, accelerates charge transport in the bulk of films, and promotes charge separation at the electrolyte/semiconductor interface. DFT simulations verify that oxygen-defective hematite has a narrow bandgap, electron-hole trapped centre, and strong adsorption energy of water molecules compared to pristine hematite. This strategy might bring PEC technology another step further towards large-scale fabrication for future commercialization.