Rational design and fabrication of multifunctional catalyzer Co2SnO4-SnO2/GC for catalysis applications: Photocatalytic degradation/catalytic reduction of organic pollutants

Abstract

Hollow porous Co2SnO4-SnO2/graphite carbon (Co2SnO4-SnO2/GC) nanocube heterojunction was designed and constructed as advanced catalytic material by calcining CoSn(OH)6 precursors followed an immersion carbon coating (using the recyclable napkin as graphite carbon source) and calcinations treatment. The design methods focus on forming intimate interfacial contacts among Co2SnO4, SnO2 and GC (in situ hybridization of the composite). The obtained Co2SnO4-SnO2/GC exhibits remarkable dual catalytic behavior including the high catalytic efficiency for photocatalytic (under visible light) degradation of chlorotetracycline (CTC)/tetracycline (TC) and catalytic reduction of p-nitrophenol (p-NP). Co2SnO4-SnO2/GC could be recycled more than four times, preserving its activity and stability based on graphite carbon protective layer on the surface of catalysts. Owing to multiple heterojunctions structure features and the synergistic effects of different junctions, greatly enhance the charge carrier generation and suppress the charge recombination of electron-hole pairs, which would be beneficial to improve its catalytic activity. The possible mechanisms for the dual-functional catalytic reactions for organic contaminants over Co2SnO4-SnO2/GC were made a thorough inquiry. This study not only shows a possibility for the utilization of low cost the recyclable napkin as a substitute for graphene but also provides a new insight into the design and construction of new heterojunction catalysts for enhancing catalytic activity.