Low-coordinated surface sites make truncated Pd tetrahedrons as robust ORR electrocatalysts outperforming Pt for DMFC devices  

作　　者：Xiaoling Wang Jingwei Li Xiaotong Yang Fengling Zhao Yongfei Li Daliang Zhang Li-Yong Gan Ke Xin Yao Qiang Yuan 

机构地区：[1]State-Local Joint Laboratory for Comprehensive Utilization of Biomass,Center for R&D of Fine Chemicals,College of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China [2]State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China [3]Key Lab of Organic Optoelectronics&Molecular Engineering,Tsinghua University,Beijing 100084,China [4]Multi-scale Porous Materials Center,Institute of Advanced Interdisciplinary Studies&School of Chemistry and Chemical Engineering,Chongqing University,Chongqing 400044,China [5]College of Physics and Center of Quantum Materials and Devices,Chongqing University,Chongqing 401331,China

出　　处：《Nano Research》2022年第9期7951-7958,共8页纳米研究（英文版）

基　　金：the National Natural Science Foundation of China(No.21571038);Education Department of Guizhou Province(No.2021312);Foundation of Guizhou Province(No.2019-5666);Science Foundation for Aftergraduated Students of Guizhou Province(No.YJSCXJH2020045);State Key Laboratory of Coal Mine Disaster Dynamics and Control(Chongqing University,No.2011DA105287-ZR202101);State Key Laboratory of Physical Chemistry of Solid Surfaces(Xiamen University,No.202009);the Open Fund of the Key Lab of Organic Optoelectronics&Molecular Engineering(Tsinghua University)。

摘　　要：Developing highly stable and active non-Pt oxygen reduction reaction(ORR)electrocatalysts for power generation device raises great concerns and remains a challenge.Here,we report novel truncated Pd tetrahedrons(T-Pd-Ths)enclosed by{111}facets with excellent uniformity,which have both low-coordinated surface sites and distinct lattice distortions that would induce“local strain”.In alkaline electrolyte,the T-Pd-Ths/C achieves remarkable ORR specific/mass activity(SA/MA)of 2.46 mA·cm^(−2)/1.69 A·mgPd^(−1),which is 12.3/16.9 and 10.7/14.1 times higher than commercial Pd/C and Pt/C,respectively.The T-Pd-Ths/C also exhibits high in-situ carbon monoxide(CO)tolerance and 50,000 cycles durability with an activity loss of 7.69%and morphological stability.The rotating ring-disk electrode(RRDE)measurements show that a 4-electron process occurs on T-PdThs/C.Theoretical calculations demonstrate that the low-coordinated surface sites contribute largely to the enhancement of ORR activity.In actual direct methanol fuel cell(DMFC)device,the T-Pd-Ths/C delivers superior open-circuit voltage(OCV)and peak power density(PPD)to commercial Pt/C from 25 to 80℃,and the maximum PPD can reach up to 163.7 mW·cm−2.This study demonstrates that the T-Pd-Ths/C holds promise as alternatives to Pt for ORR in DMFC device.

关 键 词：Pd tetrahedrons low-coordinated sites lattice distortion oxygen reduction reaction direct methanol fuel cells 

分 类 号：O643.36[理学—物理化学]