Huang Shaoda, Wang Jinyan, Hu Hongyin, Li Yang, Xu Fangping, Duan Fang, Zhu Han, Lu Shuanglong, Du Mingliang
Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China.
Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application, School of Physical Science and Technology, Suzhou University of Science and Technology, Suzhou 215009, PR China.
J Colloid Interface Sci. 2023 Jan 15;630(Pt A):375-384. doi: 10.1016/j.jcis.2022.09.139. Epub 2022 Oct 10.
The methanol-poisoning of electrocatalysts at the cathodic part of direct methanol fuel cells (DMFCs) can severely degrade the overall efficiency. Therefore, engineering cathodic catalysts with outstanding oxygen reduction activity, and simultaneously, superior methanol tolerance is greatly desired. Herein, bimetallic palladium-copper (PdCu) nanoplates with the optimized d-band center are designed as promising cathodic catalysts for DMFCs. It shows outstanding oxygen reduction activity with a mass activity (MA) of 0.522 A mg in alkaline electrolyte, overwhelming the benchmarked commercial Pt/C and Pd/C. Meanwhile, it has prominent stability with only 4.0 % loss in MA after continuous 20 K cycles. More importantly, the PdCu nanoplates are almost inert toward methanol oxidation and show excellent anti-methanol capability. The theoretical calculations reveal that the downshift of d-band center in PdCu nanoplates and the electronic interaction between Pd and Cu atoms could effectively lower the methanol adsorption energy, thus leading to enhanced methanol tolerance. This work highlights the important role of tuning the electronic structure and optimized geometry of electrocatalysts to simultaneously boost their oxygen reduction activity, stability, and methanol tolerance for their future application in DMFCs.
直接甲醇燃料电池（DMFC）阴极部分的电催化剂甲醇中毒会严重降低整体效率。因此，迫切需要设计出具有出色氧还原活性且同时具有优异甲醇耐受性的阴极催化剂。在此，具有优化d带中心的双金属钯 - 铜（PdCu）纳米片被设计为用于DMFC的有前景的阴极催化剂。它在碱性电解质中表现出出色的氧还原活性，质量活性（MA）为0.522 A mg，超过了基准商业Pt/C和Pd/C。同时，它具有突出的稳定性，在连续20K次循环后MA仅损失4.0%。更重要的是，PdCu纳米片对甲醇氧化几乎呈惰性，表现出优异的抗甲醇能力。理论计算表明，PdCu纳米片中d带中心的下移以及Pd和Cu原子之间的电子相互作用可以有效降低甲醇吸附能，从而提高甲醇耐受性。这项工作突出了调整电催化剂的电子结构和优化几何结构对于同时提高其氧还原活性、稳定性和甲醇耐受性以用于未来DMFC应用的重要作用。
