d‐Electrons of Platinum Alloy Steering CO Pathway for Low‐Charge Potential Li‐CO2 Batteries

• Published in: Angewandte Chemie International Edition 2025-01, Vol.64 (3), p.e202415728-n/a
• Main Authors: Liu, Limin, Shen, Shenyu, Li, Jiatian, Zhao, Ning, Yin, Xiangkai, Zhao, Hongyang, Yu, Wei, Su, Yaqiong, Xia, Bao Yu, Ding, Shujiang
• Format: Article
• Language: English
• Subjects: Batteries; Carbon dioxide; Carbon fibers; Cathodes; Charging; Cobalt base alloys; Cobalt compounds; d-band center; Electrochemical CO2 reduction; Electrons; Energy efficiency; Intermetallic compounds; Li-CO2 batteries; Lithium carbonate; Oxidation; Platinum base alloys; Platinum compounds; Pt-based catalysts; Reaction kinetics; Reaction pathway; Side reactions; Steering
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202415728

Aprotic Li‐CO2 batteries suffer from sluggish solid‐solid co‐oxidation kinetics of C and Li2CO3, requiring extremely high charging potentials and leading to serious side reactions and poor energy efficiency. Herein, we introduce a novel approach to address these challenges by modulating the reaction pathway with tailored Pt d‐electrons and develop an aprotic Li‐CO2 battery with CO and Li2CO3 as the main discharge products. Note that the gas‐solid co‐oxidation reaction between CO and Li2CO3 is both kinetically and thermodynamically more favorable. Consequently, the Li‐CO2 batteries with CoPt alloy‐supported on nitrogen‐doped carbon nanofiber (CoPt@NCNF) cathode exhibit a charging potential of 2.89 V at 50 μA cm−2, which is the lowest charging potential to date. Moreover, the CoPt@NCNF cathode also shows exceptional cycling stability (218 cycles at 50 μA cm−2) and high energy efficiency up to 74.6 %. Comprehensive experiments and theoretical calculations reveal that the lowered d‐band center of CoPt alloy effectively promotes CO desorption and inhibits further CO reduction to C. This work provides promising insights into developing efficient and CO‐selective Li‐CO2 batteries. The solid‐solid co‐oxidation of C and Li2CO3 is characterized by sluggish kinetics and unfavorable thermodynamics. Herein, the reaction pathway is successfully steered to a kinetically and thermodynamically favorable gas‐solid reaction between CO and Li2CO3 by optimizing the Pt d‐electron configuration. This strategy effectively improves the energy efficiency and cycle life of Li‐CO2 batteries.