title: Silver phosphate/graphitic carbon nitride as an efficient photocatalytic tandem system for oxygen evolution.
abstract: Herein, we show the facile synthesis of an efficient silver phosphate/graphitic carbon nitride (Ag3 PO4 /g-C3 N4 ) photocatalyst for oxygen production and pollutant degradation by using electrostatically driven assembly and ion-exchange processes. The composite materials demonstrate a sheet-like C3 N4 structure, decorated with different Ag3 PO4 particles sizes. Detailed analysis of the reactions mechanism by electron-spin resonance and radical-capture agents strongly imply the formation of an in situ Z-scheme by the evolution of small silver nanoparticles in the interface of the materials under illumination. The Ag nanoparticles improve charge separation within the composite material by acting as a storage and recombination center for electrons and holes from Ag3 PO4 and C3 N4 , respectively. In addition, the photostability of Ag3 PO4 is enhanced relative to that of the bulk materials, which results in a stabilized heterojunction. We believe that this work provides new insight into the operation mechanism of composite photocatalysts for water splitting and opens the possibility for advanced photocatalysis based on the higher oxidation power of Ag3 PO4 .
authors.affiliation: Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam (Germany); School of Materials Science and Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (P.R. China).
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Yang
authors.forename: Hua
authors.initials: H
authors.lastname: Tang
authors.forename: Jingsan
authors.initials: J
authors.lastname: Xu
authors.forename: Markus
authors.initials: M
authors.lastname: Antonietti
authors.forename: Menny
authors.initials: M
authors.lastname: Shalom
mesh_terms: D002384:Catalysis; D006108:Graphite / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D009570:Nitriles / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D055668:Photochemical Processes; D018030:Silver Compounds / Q000737:chemistry*
chemical_list: D009570:Nitriles; D010710:Phosphates; D018030:Silver Compounds; C011206:cyanogen; D006108:Graphite; D010100:Oxygen; C039072:silver phosphate
keywords: nanostructures; nitrides; oxygen evolution; photocatalysis; silver phosphate