A readily synthesis of oxygen vacancy-induced In(OH)3/carbon nitride 0D/2D heterojunction for enhanced visible-light-driven nitrogen fixation

A promising and practicable catalyst is the key challenge for industrial perspective to promote photocatalytic nitrogen fixation. In this study, a new 0D /2D heterojunction, oxygen vacancy-induced In(OH) 3 /carbon nitride (OV-In(OH) 3 /CN), was synthesized by generating In(OH) 3 nanoparticles on g-C 3 N 4 nanosheets in the presence of glyoxal through a facile and readily precipitation growth method at 60℃and under atmospheric pressure. The existence of oxygen vacancies, structure, morphology and optical-electronic properties of the composite were characterized by HRTEM, XPS and EPR analysis and other measurements. The OV-In(OH) 3 /CN heterojunction exhibited excellent photocatalytic activity for nitrogen fixation with a good chemical stability. The OV-In/CN-3 sample reached the maximum NH 3 generation rate to be 3.81 mM*h −1 *g −1 , which was about 10 times as that of pure g-C 3 N 4 and was also higher than that of other catalysts reported. Though the In(OH) 3 in heterojunction was demonstrated incapable of producing photogenerated electrons under vis-light irradiation, its oxygen vacancy was found to “receive” and “trap” some excited electrons from g-C 3 N 4 , promoting electron-hole pairs separation efficiency and prolonging the lifetime of carriers. And it also can introduce many chemisorption sites for N 2 . Those are the two key reasons for its high photocatalytic activity.