Solar-light-active silver phosphate/titanium dioxide/silica heterostructures for photocatalytic removal of organic dye

By Nadeem Raza, Waseem Raza, Hajera Gul, M. Azam, Jechan Lee, Kumar Vikrant, Ki‐Hyun Kim. 2020

139 citations recorded by the source corpus.

Abstract A synergistic combination of surface adsorption capabilities and photocatalytic efficiency is crucial for the removal of pollutants from water. Here, the efficacy of such a process is explored through the assembly of a heterostructured photocatalyst (Ag3PO4/TiO2/SiO2) by loading silver phosphate (Ag3PO4) onto titanium dioxide (TiO2: P25)-coated silica (SiO2) felt. This heterostructure demonstrated an enhanced tendency to absorb light due to its significantly low band-gap energy of 2.5 eV. As such, it exhibited enhanced photocatalytic performance to efficiently degrade an organic dye (methylene blue) under solar-light irradiation (e.g., 30% and 10% relative to pristine P25 and P25-coated SiO2 felt, respectively). The maximum degradation efficiency for methylene blue was 99% with a first-order kinetic model (k = 0.39 min−1). The calculated quantum yield of Ag3PO4/TiO2/SiO2 (3.26 × 10−3 molecules/photon) was significantly higher than that of other photocatalytic systems (e.g., ∼3260 times other reported hetrostructures, e.g., rGO/TiO2, Ni-doped/TiO2, and Cds/CoFe2O4) with good reusability in terms of the degradation efficiency (e.g., 99% for the first cycle and 81% for the fourth). Ag3PO4/TiO2/SiO2 is therefore recommended for the efficient treatment of organic pollutants in wastewater systems.

Subfields: Materials Chemistry, Renewable Energy, Sustainability and the Environment

View Paper: https://www.semanticscholar.org/paper/45e85f7e81c68a97272dbb5f7b5f23c93c00b63c