Abstract
Development of efficient and robust electrocatalysts is critical for practical fuel cells. We report one-dimensional bunched platinum-nickel (Pt-Ni) alloy nanocages with a Pt-skin structure for the oxygen reduction reaction that display high mass activity (3.52 amperes per milligram platinum) and specific activity (5.16 milliamperes per square centimeter platinum), or nearly 17 and 14 times higher as compared with a commercial platinum on carbon (Pt/C) catalyst. The catalyst exhibits high stability with negligible activity decay after 50,000 cycles. Both the experimental results and theoretical calculations reveal the existence of fewer strongly bonded platinum-oxygen (Pt-O) sites induced by the strain and ligand effects. Moreover, the fuel cell assembled by this catalyst delivers a current density of 1.5 amperes per square centimeter at 0.6 volts and can operate steadily for at least 180 hours.
| Original language | English |
|---|---|
| Pages (from-to) | 850-856 |
| Number of pages | 7 |
| Journal | Science |
| Volume | 366 |
| Issue number | 6467 |
| DOIs | |
| Publication status | Published - 15 Nov 2019 |
Funding
We thank S. Liao from South China University of Technology for support with the fuel cell test. We thank X. Guo from Huazhong University of Science and Technology for valuable discussions. We thank Y. Iwasawa for support with XAFS measurements and the New Energy and Industrial Technology Development Organization (NEDO), Ministry of Economy, Trade, and Industry (METI), Japan; XAFS measurements were performed with SPring-8 subject numbers 2018B7800 and 2019A7800. Supercomputing facilities were provided by Netherlands Organisation for Scientific Research (NWO). The authors also acknowledge the support of the Analytical and Testing Center of Huazhong University of Science and Technology for XRD, XPS, ICP-OES, SEM, and TEM measurements. This work is funded by the National Natural Science Foundation of China (21805104 and 21802048), the National 1000 Young Talents Program of China and the Fundamental Research Funds for the Central Universities (2018KFYXKJC044, 2018KFYYXJJ121, and 2017KFXKJC002), and the Start-up Research Foundation of Hainan University [KYQD(ZR)1908]. X.W.L. acknowledges funding support from the National Research Foundation (NRF) of Singapore via the NRF Investigatorship (NRF-NRFI2016-04).