Highly active Ag/C nanoparticles containing ultra-low quantities of sub-surface Pt for the electrooxidation of glycerol in alkaline media

The practical application of Pt-based technologies depends on the lowering in the costs and one way to face this challenge is by reducing the amount of Pt. Herein, we decorate Ag nanoparticles with ultra-small (0.8 %) quantities of Pt and test them for the electrooxidation of glycerol. We showed that the Pt atoms of our catalyst are one order of magnitude more active (in terms of mass activity) than Pt/C commercial catalyst. By performing in situ FTIR measurements, electrolysis experiments and HPLC analysis, we showed that both catalysts form mainly glycerate and lactate, but Pt/C is more prone to poisoning and to form carbonate. We suggest that this different behavior is attributed to the high dispersion of the Pt atoms on Ag nanoparticles. The lower probability of finding neighboring Pt atoms diminishes the formation of multiple bonded intermediates, which are precursors for the formation of carbonate and some poisoning intermediates. PSF thanks Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) (grants: 2016/01365-0, 2017/11986-5, 2018/20952-0). CCL thanks Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001. J.S-G. also acknowledges financial support from VITC (Vicerrectorado de Investigación y Transferencia de Conocimiento) of the University of Alicante (UATALENTO16-02). We also thanks Prof. M.A. Zezzi and Luana F. da Costa for the ICP analysis. The authors also extend gratitude to CNPEM open-facilities (LME, and LNNano) and Synchrotron Light Laboratory, CNPEM/MCTIC under proposals 20180571 and 20171115.