A β-cyclodextrin Modified Graphitic Carbon Nitride with Au Co-Catalyst for Efficient Photocatalytic Hydrogen Peroxide Production.

Yuqian Zhang,Guifu Zuo,Shanshan Liu,Liwei Feng,Lijuan Li,Ning Zhang,Gopalan Saianand,Zhaoliang Guo,Qiannan Zhao,Xianguang Meng,Vellaisamy A. L. Roy,Wangze Li

doi:10.3390/nano10101969

Abstract

Photocatalytic hydrogen peroxide (H2O2) production has attracted considerable attention as a renewable and environment-friendly method to replace other traditional production techniques. The performance of H2O2 production remains limited by the inertness of graphitic carbon nitride (CN) towards the adsorption and activation of O2. In this work, a photocatalyst comprising of β-cyclodextrin (β-CD)-modified CN with supporting Au co-catalyst (Au/β-CD-CN) has been utilized for effective H2O2 production under visible light irradiation. The static contact angle measurement suggested that β-CD modification increased the hydrophobicity of the CN photocatalyst as well as its affinity to oxygen gas, leading to an increase in H2O2 production. The rate of H2O2 production reached more than 0.1 mM/h under visible-light irradiation. The electron spin resonance spectra indicated that H2O2 was directly formed via a 2-electron oxygen reduction reaction (ORR) over the Au/β-CD-CN photocatalyst.

Highlights

Hydrogen peroxide (H2O2), is an oxidant and an important product and/or a by-product in chemical and environmental protection [1,2,3,4,5]
We found a new method to further improve the performance of Au/carbon nitride (CN) for photocatalytic H2O2 synthesis by the modification of β-cyclodextrin (β-CD) on CN (β-CD-CN)
The Au/β-Cyclodextrin–Carbon Nitride (β-CD-CN) hybrid was very inert to catalyze the decomposition of H2O2, which was beneficial to the production of concentrated H2O2

Summary

Introduction

Hydrogen peroxide (H2O2), is an oxidant and an important product and/or a by-product in chemical and environmental protection [1,2,3,4,5]. Compared with the anthraquinone method, the photocatalytic H2O2 production over semiconductors, such as TiO2 [7,8], ZnO [9,10], BiVO4 [11,12], and carbon nitride (CN) [13,14,15,16,17] is an ideal pathway that only uses solar light as driving force. An important strategy is loading proper co-catalyst on the surface of a photocatalyst to promote the charge separation and the activation of O2 [19,20]. In the liquid reaction system, the H2O2 production is limited by the adsorption of oxygen gas on photocatalyst because of the low solubility of oxygen gas in water and the inert surface nature of CN. The Au/β-CD-CN hybrid was very inert to catalyze the decomposition of H2O2, which was beneficial to the production of concentrated H2O2

Methods

Results

Conclusion