Surface-state-induced upward band bending in P doped g-C3N4 for the formation of an isotype heterojunction between bulk g-C3N4 and P doped g-C3N4: photocatalytic hydrogen production. Issue 23 (16th October 2020)

• Record Type: Journal Article
• Authors: Thangavel, Nithya; Pandi, Kavitha; Shaheer, A. R. Mahammed; Neppolian, Bernaurdshaw
• Is Part Of: Catalysis science & technology. Volume 10:Issue 23(2020)
• Page Start: 8015
• Page End: 8025
• Publication Date: 2020-10-16
• Subjects: Catalysis -- Periodicals; 541.395
• DOI: 10.1039/d0cy01543a
• Languages: English
• ISSNs: 2044-4753

Abstract

Abstract : The staggered type heterojunction with g-C3 N4 based nanomaterials has received much attention owing to its change in chemical potential between two semiconductors. Abstract : The staggered type heterojunction with g-C3 N4 based nanomaterials has received much attention owing to its change in chemical potential between two semiconductors. As a result, the migration of charge carriers occurs via the interface electric field when the semiconductor band bends upward or downward. Herein, we made an isotype heterojunction between bulk g-C3 N4 and bulk P–g-C3 N4 by forming a surface P–C bond between them. The maximum hydrogen production of 1.6 mmol h −1 g −1 is obtained for the optimized heterojunction catalysts, which is 5.3 and 2.6 times higher than those of bulk g-C3 N4 (0.30 mmol h −1 g −1 ) and bulk P–g-C3 N4 (0.60 mmol h −1 g −1 ). Thus, the formation of surface P–C bonds hinders the charge carrier recombination on various parts of the heterojunction via enhancing the spatial charge separation and prolonged carrier lifetime. Besides, the altered electronic structure, interaction between g-C3 N4 and P–g-C3 N4, relocated work functions of P–g-C3 N4 and distinct band edge positions were formed, which are responsible for the improved photocatalytic activity. Furthermore, the upward band bending of P–g-C3 N4 and its higher delocalization ability led to higher conductivity and largely prevented electron–hole pair recombination.