TY - JOUR

T1 - Surface modification of TiO2 with Pd nanoparticles for enhanced photocatalytic oxidation of benzene micropollutants

AU - Selishchev, Dmitry

AU - Svintsitskiy, Dmitry

AU - Kovtunova, Larisa

AU - Gerasimov, Evgeny

AU - Gladky, Alexey

AU - Kozlov, Denis

N1 - Funding Information: This study was funded by the Russian Science Foundation [grant number 17-73-10342 ], by the Council on grants of the President of the Russian Federation [grant number 075-15-2019-1086 ( MК-3483.2019.3 )], and by the Russian Foundation for Basic Research [grant number 18-29-17055 ]. The study was conducted using the equipment of the Center of Collective Use “National Center of Catalyst Research”. Publisher Copyright: © 2020 Elsevier B.V. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2021/3/5

Y1 - 2021/3/5

N2 - This paper describes a simple method for the modification of TiO2 surface with palladium to prepare a highly active photocatalyst for oxidation of benzene micropollutants in air. The method consists of the impregnation of anatase TiO2 with a solution of palladium (II) acetate (Pd(OAc)2) in acetone followed by photodecomposition of Pd(OAc)2 under UV irradiation. No additional electron donor is required for Pd photodeposition because acetate ligands play this role. Photodecomposition of Pd(OAc)2 can be efficiently performed either before the target photocatalytic reaction or in situ during the reaction. Pd-loaded photocatalysts were characterized using UV–vis DRS, XPS, TEM, EDX, and CO chemisorption techniques. The formation of metallic (Pd0) and oxidized (PdOx) palladium on the TiO2 surface was shown. An increased amount of metallic Pd was observed during photodecomposition of Pd(OAc)2 compared to its thermal decomposition at low temperature. The modification of TiO2 with Pd nanoparticles substantially increased its photocatalytic activity in the oxidation of benzene vapor under UV light. A Pd content of 1 wt.% was found to be optimum, which provided a three-fold increase in activity compared to pristine TiO2. In addition to increasing the oxidation rate, Pd nanoparticles suppressed the formation of CO as a byproduct during the process that increased the efficiency of air purification by the photocatalytic oxidation method. The proposed preparation techniques can be employed for easy modification of powdered photocatalysts or fabric filters used in photocatalytic air purifiers.

AB - This paper describes a simple method for the modification of TiO2 surface with palladium to prepare a highly active photocatalyst for oxidation of benzene micropollutants in air. The method consists of the impregnation of anatase TiO2 with a solution of palladium (II) acetate (Pd(OAc)2) in acetone followed by photodecomposition of Pd(OAc)2 under UV irradiation. No additional electron donor is required for Pd photodeposition because acetate ligands play this role. Photodecomposition of Pd(OAc)2 can be efficiently performed either before the target photocatalytic reaction or in situ during the reaction. Pd-loaded photocatalysts were characterized using UV–vis DRS, XPS, TEM, EDX, and CO chemisorption techniques. The formation of metallic (Pd0) and oxidized (PdOx) palladium on the TiO2 surface was shown. An increased amount of metallic Pd was observed during photodecomposition of Pd(OAc)2 compared to its thermal decomposition at low temperature. The modification of TiO2 with Pd nanoparticles substantially increased its photocatalytic activity in the oxidation of benzene vapor under UV light. A Pd content of 1 wt.% was found to be optimum, which provided a three-fold increase in activity compared to pristine TiO2. In addition to increasing the oxidation rate, Pd nanoparticles suppressed the formation of CO as a byproduct during the process that increased the efficiency of air purification by the photocatalytic oxidation method. The proposed preparation techniques can be employed for easy modification of powdered photocatalysts or fabric filters used in photocatalytic air purifiers.

KW - Benzene degradation

KW - Complete oxidation

KW - Pd nanoparticles

KW - Photodeposition

KW - TiO photocatalyst

KW - UV LED

UR - http://www.scopus.com/inward/record.url?scp=85098093265&partnerID=8YFLogxK

U2 - 10.1016/j.colsurfa.2020.125959

DO - 10.1016/j.colsurfa.2020.125959

M3 - Article

AN - SCOPUS:85098093265

VL - 612

JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects

JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects

SN - 0927-7757

M1 - 125959

ER -