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Rare Earth Evoked Subsurface Oxygen Species in Platinum Alloy Catalysts Enable Durable Fuel Cells |
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| Authors: | Liting Yang Jingsen Bai Nanshu Zhang Prof Zheng Jiang Dr Ying Wang Prof Meiling Xiao Prof Changpeng Liu Dr Siyuan Zhu Prof Zhichuan J Xu Prof Junjie Ge Prof Wei Xing |
| Institution: | 1. State Key Laboratory of Electroanalytical Chemistry, Laboratory of Advanced Power Sources, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022 Changchun, China
School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026 Hefei, China;2. School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026 Hefei, China Shanghai Synchrotron Radiation Facility, Zhangjiang National Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201204 Shanghai, China;3. State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022 Changchun, China;4. State Key Laboratory of Electroanalytical Chemistry, Laboratory of Advanced Power Sources, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022 Changchun, China;5. School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore;6. School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026 Hefei, China |
| Abstract: | Alleviating the degradation issue of Pt based alloy catalysts, thereby simultaneously achieving high mass activity and high durability in proton exchange membrane fuel cells (PEMFCs), is highly challenging. Herein, we provide a new paradigm to address this issue via delaying the place exchange between adsorbed oxygen species and surface Pt atoms, thereby inhibiting Pt dissolution, through introducing rare earth bonded subsurface oxygen atoms. We have succeeded in introducing Gd?O dipoles into Pt3Ni via a high temperature entropy-driven process, with direct spectral evidence attained from both soft and hard X-ray absorption spectroscopies. The higher rated power of 0.93 W cm?2 and superior current density of 562.2 mA cm?2 at 0.8 V than DOE target for heavy-duty vehicles in H2-air mode suggest the great potential of Gd?O?Pt3Ni towards practical application in heavy-duty transportation. Moreover, the mass activity retention (1.04 A mgPt?1) after 40 k cycles accelerated durability tests is even 2.4 times of the initial mass activity goal for DOE 2025 (0.44 A mgPt?1), due to the weakened Pt?Oads bond interaction and the delayed place exchange process, via repulsive forces between surface O atoms and those in the sublayer. This work addresses the critical roadblocks to the widespread adoption of PEMFCs. |
| Keywords: | Fuel Cells Oxygen Reduction Reaction Place Exchange Process Pt Durability |