Clean synthesis of RGO/Mn3O4 nanocomposite with well-dispersed Pd nanoparticles as a high-performance catalyst for hydroquinone oxidation

Yao Ma; Conghui Si; Xing Yang; Jianan Li; Zhezhao Wang; Xuezhao Shi; Weichun Ye; Panpan Zhou; Wojciech M Budzianowski

doi:10.1016/j.jcis.2019.05.009

Clean synthesis of RGO/Mn₃O₄ nanocomposite with well-dispersed Pd nanoparticles as a high-performance catalyst for hydroquinone oxidation

J Colloid Interface Sci. 2019 Sep 15:552:72-83. doi: 10.1016/j.jcis.2019.05.009. Epub 2019 May 3.

Authors

Yao Ma¹, Conghui Si², Xing Yang¹, Jianan Li¹, Zhezhao Wang¹, Xuezhao Shi¹, Weichun Ye³, Panpan Zhou⁴, Wojciech M Budzianowski⁵

Affiliations

¹ Department of Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Lanzhou University, Lanzhou 730000, China.
² Key Laboratory of Processing and Testing Technology of Glass and Functional Ceramics of Shandong Province, School of Material Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
³ Department of Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Lanzhou University, Lanzhou 730000, China. Electronic address: yewch@lzu.edu.cn.
⁴ Department of Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Lanzhou University, Lanzhou 730000, China. Electronic address: zhoupp@lzu.edu.cn.
⁵ Wojciech Budzianowski Consulting Serv, Poleska 11-37, PL-51354 Wroclaw, Poland. Electronic address: wojciech@budzianowski.eu.

PMID: 31103892
DOI: 10.1016/j.jcis.2019.05.009

Abstract

In this study, a well-dispersed Pd nanoparticle (NP)-supported RGO/Mn₃O₄ (G/M/Pd) composite was synthesized by a clean synthetic route, where galvanic replacement reaction simply occurred between Mn₃O₄ and a palladium salt, thereby avoiding the use of harsh reducing and capping agents. The G/M/Pd composite served as a robust catalyst for the catalytic oxidation of hydroquinone (HQ) to benzoquinone (BQ) with H₂O₂ in an aqueous solution. Oxidation was completed in only 4 min, with a turnover frequency (TOF) of 3613 h^-1; this TOF is one hundred times those of previously reported Pd- and Ag-based catalysts. The superior performance was related to the electronic inductive effect between Mn₃O₄ and Pd NPs, which was verified by density functional theory calculations. Trapping experiments revealed that the oxidation of HQ was considerably related to the ·OH radicals generated from the decomposition of H₂O₂. In addition, the influencing factors were further investigated, including catalyst and HQ concentrations, solution pH, solvents, and various inorganic and organic interferences. Moreover, the G/M/Pd catalyst exhibits diverse applications for the catalytic oxidation of HQ derivatives with high TOFs.

Keywords: Density functional theory (DFT) calculation; Galvanic replacement; Hydroxyl radicals; Mn(3)O(4); Oxidation of hydroquinone.