摘要
为金属空气电池等热点能源器件中的阴极氧还原反应(ORR)设计低成本和高效率的无贵金属催化剂仍然是一项巨大的挑战。过渡金属磷化物(TMPs)因其可调的电子结构及优异的催化性能,有望替代贵金属催化剂。本文采用磷化策略(350℃下二次热解),构建了一种在分层多孔炭框架上负载由掺氮炭壳包裹的CoP纳米颗粒催化剂(CoP@NC)。在二次热解过程中,Co纳米颗粒在NaH_(2)PO_(2)生成的PH_(3)气体下原位转化为CoP纳米颗粒,而载体的十二面体结构没有发生改变。在碱性条件下,CoP@NC电催化剂表现出优异的ORR活性,半波电位高达0.92 V,这归因于分散良好的CoP纳米颗粒与炭壳之间的协同耦合以及载体多孔结构实现的高效质量传输。此外,使用CoP@NC组装的锌-空气电池展现出1.51 V的高开路电压和210.1 mW cm^(-2)的功率密度。这项研究将有助于开发低成本和高效率的ORR电催化剂。
Exploring cost-efficient and highly-efficient noble metal-free catalysts for the oxygen reduction reactions(ORRs)in-volved in sustainable energy devices remains a great challenge.Transition-metal phosphides supported on heteroatom-doped carbons have shown potential as alternative candidates for precious metals because of their tunable electronic structures and higher catalytic performance.Phosphating was used to construct CoP nanoparticles(NPs)anchored on a nitrogen-doped porous carbon framework(CoP@NC)from Co NPs loaded on NC,using PH_(3)gas released from NaH_(2)PO_(2)during heat treatment.The dodecahedral structure of Co NPs was retained in their transformation to CoP NPs.The CoP@NC electrocatalyst shows a remarkable ORR activity with a half-wave potential up to 0.92 V under alkaline conditions,which is attributed to the combined coupling between the well dispersed CoP nanoparticles on the nitrogen-doped carbon and the efficient mass transport in the porous structure.Zinc-air batteries assembled with the CoP@NC electrocatalyst as a cathode have a high open-circuit voltage of 1.51 V and power density of 210.1 mW cm^(-2).This work provides a novel strategy to develop low-cost catalysts with an excellent ORR performance to promote their practical use in metal-air batteries.
作者
闫晓丽
王奎
郝姝葳
周广达
杨浩伟
张华
郭俊杰
YAN Xiao-li;WANG Kui;HAO Shu-wei;ZHOU Guang-da;YANG Hao-wei;ZHANG Hua;GUO Jun-jie(Key Laboratory of Interface Science and Engineering in Advanced Materials,Ministry of Education,College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;College of Materials Science and Engineering,Huaqiao University,Xiamen 361021,China)
出处
《新型炭材料（中英文）》
SCIE
EI
CAS
CSCD
北大核心
2024年第3期526-537,共12页
New Carbon Materials
基金
国家自然科学基金(12305332)
山西省自然科学基金(202203021221089)
山西省科技创新人才团队项目(202304051001010)
山西省高等学校科技创新项目(2019L0253)
山西省高等学校创新人才计划(PTIT).
