Photocatalytic H2O2 Generation Using Au-Ag Bimetallic Alloy Nanoparticles loaded on ZnO

Abstract

Hydrogen peroxide (H2O2) is an important chemical as it is an environmentally friendly oxidant for organic synthesis and environmental remediation as well as a promising candidate for the liquid fuel. Photocatalytic generation of H2O2 is sustainable, and many efforts have been put into the development of new catalysts to gain high H2O2 yields. In this investigation, Au/ZnO, Ag/ZnO and Au-Ag/ZnO catalysts were prepared by the simultaneous impregnation of HAuCl4 and AgNO3 and they were used to generate H2O2 from a methanol/O2 system. It was demonstrated that Au/ZnO had the best performance at generating H2O2. The presence of Au on ZnO accelerated the generation of H2O2 on ZnO and facilitated H2O2 adsorption onto the catalyst surface, which resulted in the reaction kinetics changing from zero-order to first-order. Ag atoms on Ag/ZnO were unstable and would strip from the surface of ZnO during irradiation, decreasing the yield of H2O2. The stabilization of Ag on Au-Ag/ZnO depended on the ratio of Au and Ag. Au0.1Ag0.2/ZnO was a stable catalyst and it showed that the presence of Ag promoted the formation and decomposition of peroxide, simultaneously.

Improved the Light Adsorption and Separation of Charge Carriers to Boost Photocatalytic Conversion of CO2 by Using Silver Doped ZnO Photocatalyst

“…ZnO had a uniform nanorod shape, while the surface of Ag-ZnO contained some small nanoparticles loading onto the nanorods of ZnO. The result from SEM analysis confirmed that the silver nanoparticles were loaded over ZnO [13,21,25].…”

“…Silver is one of the cheapest, most stable, and non-toxic of the noble metals; with surface plasmon resonance it also can support enhancing light adsorption as well. The doped Ag onto ZnO was determined to improve the photocatalytic decomposition of methylene blue [13,15,25].…”

Hydrogen Peroxide Production by Inorganic Photocatalysts Consisting of Gold Nanoparticle and Metal Oxide toward Oxygen Cycle Chemistry

“…The development of the catalyst with higher activity and selectivity for 2e – -ORR in addition to lower activity for H 2 O 2 decomposition than Au NP is the central subject. An effective means to improve the catalytic performance is alloying Au with other metals such as Ag , and Pd . Also, antimony-doped tin oxide is a very promising nonprecious MO due to the high activity for 2e – -ORR, low affinity for H 2 O 2 , extreme robustness, and the applicability to the electrochemical production of H 2 O 2 …”

Fenton reaction by H2O2 produced on a magnetically recyclable Ag/CuWO4/NiFe2O4 photocatalyst

“…18 In addition, Ag NPs show interesting 2e − O 2 reduction behavior and oxygen adsorption properties. 26–29…”

“…18 In addition, Ag NPs show interesting 2e − O 2 reduction behavior and oxygen adsorption properties. [26][27][28][29] There is no previous report on the photocatalytic H 2 O 2 formation properties of the magnetically recyclable Ag/ CuWO 4 /NiFe 2 O 4 composite. Furthermore, the H 2 O 2 produced is used for in situ Fenton-like degradation of tetracycline.…”