MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, State Key Lab of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China.
College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
ACS Appl Mater Interfaces. 2022 Dec 7;14(48):53819-53827. doi: 10.1021/acsami.2c15996. Epub 2022 Nov 22.
Developing low-loading Pt-based catalysts possessing glorious catalytic performance can accelerate oxygen reduction reaction (ORR) and hence significantly advance the commercialization of proton exchange membrane fuel cells. In this report, we propose a hybrid catalyst that consists of low-loading sub-3 nm PtCo intermetallic nanoparticles carried on Co-N-C (PtCo/Co-N-C) via the microwave-assisted polyol procedure and subsequent heat treatment. Atomically dispersed Co atoms embedded in the Co-N-C carriers diffuse into the lattice of Pt, thus forming ultrasmall PtCo intermetallic nanoparticles. Owing to the dual effect of the enhanced metal-support interaction and alloy effect, as-fabricated PtCo/Co-N-C catalysts deliver an extraordinary performance, achieving a half-wave potential of 0.921 V, a mass activity of 0.700 A mg@0.9 V, and brilliant durability in the acidic medium. The fuel cell employing PtCo/Co-N-C as the cathode catalyst with an ultralow Pt loading of 0.05 mg cm exhibits an impressive peak power density of 0.700 W cm, higher than that of commercial Pt/C under the same condition. Furthermore, the enhanced intrinsic ORR activity and stability are imputed to the downshifted d-band center and the strengthened metal-support interaction, as revealed by density functional theory calculations. This report affords a facile tactic to fabricate Pt-based alloy composite catalysts, which is also applicable to other alloy catalysts.
开发具有出色催化性能的低负载量 Pt 基催化剂可以加速氧还原反应（ORR），从而显著推进质子交换膜燃料电池的商业化进程。在本报告中，我们提出了一种通过微波辅助多元醇法和随后的热处理将负载量低于 3nm 的亚纳米 PtCo 金属间化合物纳米颗粒负载在 Co-N-C 上的杂化催化剂（PtCo/Co-N-C）。嵌入在 Co-N-C 载体中的原子分散的 Co 原子扩散到 Pt 的晶格中，从而形成了超小的 PtCo 金属间化合物纳米颗粒。由于增强的金属-载体相互作用和合金效应的双重作用，所制备的 PtCo/Co-N-C 催化剂表现出非凡的性能，在酸性介质中实现了 0.921V 的半波电位、0.700A mg@0.9V 的质量活性和出色的耐久性。在相同条件下，采用负载量低至 0.05mg cm 的 PtCo/Co-N-C 作为阴极催化剂的燃料电池表现出令人印象深刻的 0.700W cm 的峰值功率密度，高于商业 Pt/C。此外，通过密度泛函理论计算揭示了增强的内在 ORR 活性和稳定性归因于 d 带中心的下移和增强的金属-载体相互作用。本报告提供了一种制备 Pt 基合金复合催化剂的简便策略，该策略也适用于其他合金催化剂。
