Lutetium-Induced Ultrafine PtRu Nanoclusters with a High Electrochemical Surface Area for Direct Methanol Fuel Cells at Alleviated Temperatures

Yi Cheng; Huiping Wang; Tian-Wen Jiang; Xinyao Guo; Felix Kwofie; Huaneng Su; Lindiwe Khotseng; Weifeng Zeng; Ying Zhang; Yujing Liu; Wen-Bin Cai; Shuangyin Wang

doi:10.1021/acsami.3c17927

Lutetium-Induced Ultrafine PtRu Nanoclusters with a High Electrochemical Surface Area for Direct Methanol Fuel Cells at Alleviated Temperatures

ACS Appl Mater Interfaces. 2024 Apr 12. doi: 10.1021/acsami.3c17927. Online ahead of print.

Authors

Yi Cheng^{1

2}, Huiping Wang^{1

2}, Tian-Wen Jiang³, Xinyao Guo⁴, Felix Kwofie^{1

2}, Huaneng Su⁵, Lindiwe Khotseng⁶, Weifeng Zeng^{1

2}, Ying Zhang⁷, Yujing Liu⁸, Wen-Bin Cai³, Shuangyin Wang⁹

Affiliations

¹ Hunan Provincial Key Laboratory of Nonferrous Value-added Metallurgy, Central South University, Changsha 410083, China.
² Engineering Research Center of the Ministry of Education for Advanced Battery Materials, Central South University, Changsha 410083, China.
³ Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, Fudan University, Shanghai 200438, China.
⁴ School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia.
⁵ Institute for Energy Research, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, PR China.
⁶ Department of Chemistry, University of the Western Cape, Robert Sobukwe Road, Cape Town 7535, South Africa.
⁷ National Engineering Research Centre of Green Recycling for Strategic Metal Resources, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
⁸ Institute of Metals, College of Material Science and Engineering, Changsha University of Science & Technology, 960, Second Section, Wanjiali RD (S), Changsha, Hunan 410004, China.
⁹ State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Provincial Hunan Key Laboratory for Graphene Materials and Devices, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.

PMID: 38606549
DOI: 10.1021/acsami.3c17927

Abstract

PtRu alloys have been recognized as the state-of-the-art catalysts for the methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs). However, their applications in DMFCs are still less efficient in terms of both catalytic activity and durability. Rare earth (RE) metals have been recognized as attractive elements to tune the catalytic activity, while it is still a world-class challenge to synthesize well-dispersed Pt-RE alloys. Herein, we developed a novel hydrogen-assisted magnesiothermic reduction strategy to prepare a highly dispersed carbon-supported lutetium-doped PtRu catalyst with ultrafine nanoclusters and atomically dispersed Ru sites. The PtRuLu catalyst shows an outstanding high electrochemical surface area (ECSA) of 239.0 m² g_Pt^-1 and delivers an optimized MOR mass activity and specific activity of 632.5 mA mg_Pt^-1 and 26 A cm_Pt^-2 at 0.4 V vs saturated calomel electrode (SCE), which are 3.6 and 3.5 times of commercial PtRu-JM and an order higher than PtLu, respectively. These novel catalysts have been demonstrated in a high-temperature direct methanol fuel cell running in a temperature range of 180-240 °C, achieving a maximum power density of 314.3 mW cm^-2. The AC-STEM imaging, in situ ATR-IR spectroscopy, and DFT calculations disclose that the high performance is resulted from the highly dispersed PtRuLu nanoclusters and the synergistic effect of the atomically dispersed Ru sites with PtRuLu nanoclusters, which significantly reduces the CO* intermediates coverage due to the promoted water activation to form the OH* to facilitate the CO* removal.

Keywords: PtRuLu; high-temperature direct methanol fuel cell; lutetium; methanol oxidation mechanism; methanol oxidation reaction.