• 文献标题:   Effect of graphene oxide on the energy level alignment and photocatalytic performance of Engelhard Titanosilicate-10
  • 文献类型:   Article
  • 作  者:   NGUANG SY, LIEW ASY, CHIN WC, TAHIR N, ARSHAD SE, CHEE FP, MOH PY
  • 作者关键词:   homolumo gap, electron affinity, work function, advanced oxidation processe, visiblelightdriven photocatalysi
  • 出版物名称:   MATERIALS CHEMISTRY PHYSICS
  • ISSN:   0254-0584 EI 1879-3312
  • 通讯作者地址:  
  • 被引频次:   1
  • DOI:   10.1016/j.matchemphys.2021.125198 EA SEP 2021
  • 出版年:   2022

▎ 摘  要

A smaller band gap with lower electron-hole recombination is required to ensure good photocatalytic performance of a photocatalyst. This study reveals that the incorporation of graphene oxide (GO) into Engelhard Titanosilicate-10 (ETS-10) forms GO/ETS-10 material with reduced optical band gap of about 2.9 eV, thereby making the GO/ETS-10 material a functional photocatalyst under regions of visible and ultraviolet radiations. Moreover, the results of ultraviolet photoelectron and low-energy inverse photoelectron spectroscopy (UPSLEIPS) show that GO is a good platform for ETS-10, which significantly lowers the electronic band gap (Eg = 4.005 eV) between the highest occupied (HOMO) and lowest unoccupied molecular orbitals (LUMO) to ease electron transport, significantly reduces the work function (WF = 4.357 eV) to facilitate excitation of electron, and significantly increases the electron affinity (EA = 4.179 eV) to slow down the electron-hole recombination. The results are in good agreement with the empirical photocatalytic degradation of aqueous methylene blue (MB) by the GO/ETS-10 material. Under ultraviolet light irradiation, photocatalytic degradation of MB by the GO/ETS-10 material (as GO/ETS-10/UV-A) shows a similar degradation rate (k1 = 1.6 x 10-3 min-1) in comparison to that under visible light irradiation (as GO/ETS-10/Vis) (k1 = 1.6 x 10-3 min-1), and double the degradation rate in comparison to that in the ETS-10/UV-A system (k1 = 0.7 x 10-3 min-1). Furthermore, the addition of 10 mM of hydrogen peroxide (H2O2) into the photocatalytic system significantly increases the rate of MB degradation with k1 = 4.8 x 10-3 min-1 for the GO/ETS-10/H2O2/UV-A system and k1 = 2.9 x 10-3 min-1 for the GO/ETS-10/H2O2/Vis system. This study illustrates that UPS-LEIPS can be a good technique to predict the performance of a solid photocatalyst, and the GO/ETS-10 material is a good photocatalyst for the degradation of organic pollutants in water.