posted on 2021-11-16, 12:37authored byKaili Wang, Danyang Huang, Yichi Guan, Feng Liu, Jia He, Yi Ding
Designing
highly efficient and durable electrocatalysts for methanol
oxidation reaction (MOR) plays a decisive role in the commercialization
of direct methanol fuel cells (DMFCs). Compared with commercial Pt/C
catalysts, fine-tuning the electronic structure of electrocatalysts
to reduce the adsorption energy of CO while at the same time increasing
the adsorption energy of OH is beneficial to improving the activity
of MOR. Herein, ultrastable self-supported PtCu nanowires (NWs) with
abundant Cu-vacancies have been developed, wherein the CO adsorption
energy is weakened by doping of Cu elements and the OH adsorption
energy is strengthened by the vacancy defect through dealloying. The
well-designed PtCu NWs exhibit an outstanding performance for the
MOR, with a specific activity 7.5 times higher than that for the commercial
Pt/C catalyst, which transcends most electrocatalysts’ performance
currently. Moreover, the stability of PtCu electrocatalysts is greatly
improved over 1 h owing to a “non-CO” pathway for MOR.
Further DMFC tests present a 2 times higher power density than that
of commercial Pt/C, and the PtCu integrated DMFC also presents a higher
stability for 24 h, transcending most Pt-based anode catalysts of
DMFCs.