TY - JOUR

T1 - Modeling and Optimization of the Photocatalytic Reduction of Molecular Oxygen to Hydrogen Peroxide over Titanium Dioxide

AU - Burek, Bastien O.

AU - Bahnemann, Detlef

AU - Bloh, Jonathan Z.

N1 - Funding information: The authors gratefully thank German Research Foundation (DFG) for funding in the grant no. BL 1425/1-1. Furthermore, we thank Dr. Dirk Holtmann, DECHEMA-Forschungsinstitut, for helpful discussions and advice and Heinrich Kopietz, Jano Bender, and Yvonne Hohmann, DECHEMA-Forschungsin-stitut machine work shop, for help with technical drawings and building of the setups.

PY - 2019/1/4

Y1 - 2019/1/4

N2 - This study focuses on understanding the mechanisms for optimization of the photocatalytic hydrogen peroxide production over TiO 2 (Aeroxide P25). Via precise control of the reaction parameters (pH, temperature, catalyst amount, oxygen content, sacrificial electron donor, and light intensity), it is possible to tune either the apparent quantum yield or the production rate. As a result of the optimization, apparent quantum yields of up to 19.8% and production rates of up to 83 μM min -1 were obtained. We also observed a light-dependent change of the reaction order and an interdependency of the light intensity and catalyst amount, and we developed a well-fitting kinetic model for it, which might also be applied to other reactions. Furthermore, a previously unreported inactivation of the photocatalyst in the case of water oxidation is described.

AB - This study focuses on understanding the mechanisms for optimization of the photocatalytic hydrogen peroxide production over TiO 2 (Aeroxide P25). Via precise control of the reaction parameters (pH, temperature, catalyst amount, oxygen content, sacrificial electron donor, and light intensity), it is possible to tune either the apparent quantum yield or the production rate. As a result of the optimization, apparent quantum yields of up to 19.8% and production rates of up to 83 μM min -1 were obtained. We also observed a light-dependent change of the reaction order and an interdependency of the light intensity and catalyst amount, and we developed a well-fitting kinetic model for it, which might also be applied to other reactions. Furthermore, a previously unreported inactivation of the photocatalyst in the case of water oxidation is described.

KW - catalyst inactivation

KW - hydrogen peroxide (H O )

KW - light intensity

KW - oxygen reduction

KW - photocatalysis

KW - titanium dioxide (TiO )

UR - http://www.scopus.com/inward/record.url?scp=85059234180&partnerID=8YFLogxK

U2 - 10.1021/acscatal.8b03638

DO - 10.1021/acscatal.8b03638

M3 - Article

VL - 9

SP - 25

EP - 37

JO - ACS catalysis

JF - ACS catalysis

SN - 2155-5435

IS - 1

ER -