(162853)Facile fabrication of nano silver phosphate on B-doped g-C_3N_4: An excellent p-n heterojunction photocatalyst towards water oxidation and Cr (VI) reduction
(162853)Facile fabrication of nano silver phosphate on B-doped g-C_3N_4: An excellent p-n heterojunction photocatalyst towards water oxidation and Cr (VI) reduction
1. Centre for Nanoscience and Nanotechnology (CNSNT), Siksha '0' Anusandhan, Bhubaneswar 751030, India
2. Physical Chemistry Division, CSIR-NCL Pune, Dr. Homi Bhaba Road, Pane 411008, India
折叠
Abstract
A photostable Ag_3PO_4/BCN type-II p-n heterojunction has been demonstrated by loading nano Ag_3PO_4 on B-doped g-C_3N_4 nanosheet (BCN). The photocatalysts were successfully characterized by various physico-chemical techniques and their photocatalytic activities were tested towards the water oxidation reaction to produce oxygen and Cr (VI) reduction under visible light. The HRTEM confirms Ag_3PO_4 with a particle size of 15 nm has been deposited on BCN to construct a p-n heterojunction. The BCNS-50 absorbs more visible light in the solar spectrum as compared to other catalyst, demonstrating the ability to generate 587 umol h~(-1)g~(-1) O_2 and reduces 98% of 20 ppm Cr (VI) solution in 1 h. The lower PL intensity as well as lower arc value in case of BCNS-50 suggests the maximum e-h separation and lower charge transfer resistance across the semiconductor/electrolyte interface. The BCN sheet provides a compact heterojunction where the oxidation peak of Ag_3PO_4 decreases gradually and disappear in case of BCNS-50 suggesting the enhance stability of Ag_3PO_4 in the heterojunction. BCNS-50 could able to produce -139 and 3087.5 uA photocurrent both in cathodic and anodic direction which is approximately 7 and 2.4 folds higher as compared to nano Ag_3PO_4. The generation of photocurrent in both cathodic and anodic direction confirms the formation of p-n heterojunction which further supported by Mott-Schottky analysis. Furthermore the construction of the p-n heterojunction is verified via Mott-Schottky study. DFT calculation explains the contribution of various atomic orbital of Ag_3PO_4 and BCN towards the formation of hybrid orbital in the heterojunction and the path for charge derealization between them. This work may provide a limelight and alternative pathway for enhanced photocatalytic performance on construction of the p-n heterojunction in a simple way.
Key words
Water oxidation/Cr (VI) reduction/P-n heterojunction/Photocatalyst/Interfacial zone/Density Functional Theory
NSTL
Elsevier