Mondal Sourav, De Sandip Kumar, Ghosh Tanmay, Mondal Subrata, Manna Mihir, Senapati Dulal
Chemical Sciences Division Homi Bhabha National Institute Saha Institute of Nuclear Physics A CI of Homi Bhabha National Institute 1/AF Bidhannagar Kolkata 700064 India.
Department of Chemistry SRICT-ISR UPL University of Sustainable Technology Vataria Gujarat 393135 India.
Small Sci. 2025 Apr 15;5(8):2500063. doi: 10.1002/smsc.202500063. eCollection 2025 Aug.
Formic acid oxidation (FAO) reaction is an important electrocatalytic reaction in low-temperature proton exchange membrane fuel cells. Pd-based material has a superior electrochemical activity towards FAO. The activity of Pd-based bimetallic materials is also well-studied in the literature. Here, we have reported the synthesis of a unique heterostructured trimetallic nanoparticle where Pd is lined along with Ag forming a certain percentage of alloy at the edges of the bimetallic Au-Ag prismatic nanotemplate. Though Pd acts as an effective material, this unique structure shows much improved catalytic activity due to the synergistic effect of Au, Ag, and Pd. Pd deposition increases the surface roughness and electrochemically active surface area. Lattice strain due to lattice mismatch between Ag and Pd modifies the d-band center, enhancing the intrinsic activity, and facilitating the reaction kinetics. Pd-deposited nanoparticle shows 3.4 and 4 times higher ECSA than monometallic cubic Pd nanoparticles and commercially available 10 wt% Pd/C. Our synthesized best catalyst Pd-1.5 shows the mass activity of 634 Ag which is ≈7 times higher than the standard 10 wt% Pd/C. Our catalyst shows higher stability and CO-tolerance due to the suppression of the dehydration pathway and the reaction proceeds mainly via the dehydrogenation pathway.
甲酸氧化（FAO）反应是低温质子交换膜燃料电池中的一种重要电催化反应。钯基材料对FAO具有优异的电化学活性。钯基双金属材料的活性在文献中也得到了充分研究。在此，我们报道了一种独特的异质结构三金属纳米颗粒的合成，其中钯与银排列在一起，在双金属金 - 银棱柱形纳米模板的边缘形成一定比例的合金。尽管钯是一种有效的材料，但由于金、银和钯的协同作用，这种独特结构显示出大大提高的催化活性。钯的沉积增加了表面粗糙度和电化学活性表面积。由于银和钯之间的晶格失配导致的晶格应变改变了d带中心，增强了本征活性，并促进了反应动力学。钯沉积的纳米颗粒的电化学活性表面积（ECSA）比单金属立方钯纳米颗粒和市售10 wt% Pd/C分别高3.4倍和4倍。我们合成的最佳催化剂Pd - 1.5的质量活性为634 Ag，约为标准10 wt% Pd/C的7倍。由于脱水途径受到抑制，我们的催化剂显示出更高的稳定性和抗CO能力，反应主要通过脱氢途径进行。
