Enhanced optoelectronic functionality of N + H codoped monoclinic WO3: A hybrid functional study

Abstract

N + H co-doping in monoclinic WO 3 has been systematically investigated using the Heyd-Scuseria-Enrzerhof hybrid functional. Results show that N and H tend to stay nearest to each other to form a N H cluster, inducing a dispersive and occupied intermediate band within the band gap of WO 3 . The presence of this intermediate band makes the band gap narrowed by 24%, leading to a remarkable redshift of the optical absorption edge. Simultaneously, the high carrier mobility is beneficial for the electron excitation, also contributable to the enhancement in the photoabsorption of WO 3 . Especially, the N H bond length is very close to that in NH 3 , suggesting that it is likely to utilize NH 3 to dope WO 3 for improved optoelectronic performance. The thermodynamic and kinetic stabilities of the N H cluster in WO 3 have been addressed in details. This work has implications in optimizing the optoelectronic functionality of WO 3 -based materials for environmentally friendly applications.