A tri-functionalised PtSnOx-based electrocatalyst for hydrogen generation via ammonia decomposition under native pH conditions

Mingzhu Wu; Jun Du; Changyuan Tao; Zuohua Liu; Ying Li

doi:10.1016/j.jcis.2019.01.085

A tri-functionalised PtSnO_x-based electrocatalyst for hydrogen generation via ammonia decomposition under native pH conditions

J Colloid Interface Sci. 2019 Apr 15:542:451-459. doi: 10.1016/j.jcis.2019.01.085. Epub 2019 Jan 22.

Authors

Mingzhu Wu¹, Jun Du², Changyuan Tao³, Zuohua Liu⁴, Ying Li⁵

Affiliations

¹ Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, PR China; Applied Technology Promotion Center of Chongqing Education Committee For Chemical Pollution Prevention and Control, Chongqing Industry Polytechnic College, Chongqing 401120, PR China.
² Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, PR China. Electronic address: dujune@cqu.edu.cn.
³ Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, PR China. Electronic address: taocy@cqu.edu.cn.
⁴ Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, PR China.
⁵ Applied Technology Promotion Center of Chongqing Education Committee For Chemical Pollution Prevention and Control, Chongqing Industry Polytechnic College, Chongqing 401120, PR China.

PMID: 30771639
DOI: 10.1016/j.jcis.2019.01.085

Abstract

Hydrogen is one of the most clean energy carriers because water is only the product of its combustion. The electrolysis of ammonia is expected to offer an attractive alternative to water electrolysis for the production of hydrogen because of the lower thermodynamic energy. However, the synthesis and utilization of high-performance Pt electrocatalysts have encountered challenges related to instability and hydroxyl ion sensitivity. To address these issues, we developed PtSnO_x-based nanoparticles that maintained high electrocatalytic activity and stability for the decomposition of aqueous ammonia to generate hydrogen under native pH conditions which means the acidity/alkalinity is not adjusted. FT-IR, XRD, and XPS evidence showed PtSnO_x was a tri-functionalised electrocatalyst. That is to say, the spherical SnO_x nanoparticles assisted ammonia adsorption and activation, which were accompanied by a hydrogen adsorption on PtSnO_x and hydrogen transfer along the SnOH bond over the electrocatalyst. According to these data of FT-IR, XRD, and XPS before and after reaction, a possible mechanism for the decomposition of aqueous ammonia to produce hydrogen was proposed. This study could pave the way to prospective routes for the selective oxidation of the NH bond to generate hydrogen under mild conditions.

Keywords: Ammonia; Decomposition; Generation; Hydrogen; PtSnO(x).