A Dual Catalyst with SERS Activity for Probing Stepwise Reduction and Oxidation Reactions

Jumei Li, Yiren Wu, Xiaojun Sun, Jingyue Liu, Sarah A. Winget, Dong Qin

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Aromatic azo compounds are high-value chemicals extensively used as pigments, drugs, and food additives, but their production typically requires stoichiometric amounts of environmentally unfriendly metals or nitrites. There is an urgent need to develop a dual catalytic system capable of reducing nitroaromatics to aromatic amines, followed by their oxidation to azo compounds. Here we report such a dual catalyst based on Ag@Pd-Ag core-frame nanocubes for the stepwise conversion of 4-nitrothiophenol to trans-4,4′-dimercaptoazobenzene under ambient conditions. Our in situ surface-enhanced Raman spectroscopy study reveals three sequential processes that include the Pd-catalyzed reduction of 4-nitrothiophenol to 4-aminothiophenol by hydrogen, a period during which the 4-aminothiophenol remain unchanged until all hydrogen has depleted, and the Ag-catalyzed oxidation of 4-aminothiophenol to trans-4,4′-dimercaptoazobenzene by the O2 from air. This work will lead to an environmentally friendly and sustainable approach to the production of aromatic azo compounds.

Original languageEnglish (US)
Pages (from-to)786-790
Number of pages5
JournalChemNanoMat
Volume2
Issue number8
DOIs
StatePublished - Jan 1 2016

Fingerprint

Azo Compounds
Thermodynamic properties
Food additives
Oxidation
Hydrogen
Catalysts
Pigments
Raman spectroscopy
Amines
Nitrites
Air
Metals
Pharmaceutical Preparations
4-aminothiophenol

Keywords

  • Ag-catalyzed oxidation
  • bimetallic nanocrystals
  • catalysis
  • Pd-catalyzed reduction

ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Renewable Energy, Sustainability and the Environment
  • Biomaterials
  • Materials Chemistry

Cite this

A Dual Catalyst with SERS Activity for Probing Stepwise Reduction and Oxidation Reactions. / Li, Jumei; Wu, Yiren; Sun, Xiaojun; Liu, Jingyue; Winget, Sarah A.; Qin, Dong.

In: ChemNanoMat, Vol. 2, No. 8, 01.01.2016, p. 786-790.

Research output: Contribution to journalArticle

Li, Jumei ; Wu, Yiren ; Sun, Xiaojun ; Liu, Jingyue ; Winget, Sarah A. ; Qin, Dong. / A Dual Catalyst with SERS Activity for Probing Stepwise Reduction and Oxidation Reactions. In: ChemNanoMat. 2016 ; Vol. 2, No. 8. pp. 786-790.
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