层状金属氢氧化物中铁位点辅助分散铂纳米颗粒用于高效甲醇氧化

Highly Dispersed Pt Nanoparticles Root in Single-Atom Fe Sites in LDHs toward Efficient Methanol Oxidation

高活性和耐用性的甲醇氧化电催化剂对于直接甲醇燃料电池的商业可行性至关重要,然而,目前的甲醇氧化电催化剂与预期相去甚远,存在贵金属用量过多、活性平庸、衰减快等问题。在这里,我们报告了锚定在镍铁层状金属氢氧化物(NiFe-LDHs)表面Pt纳米颗粒复合材料,用于在碱性介质中稳定电催化甲醇氧化。基于Pt纳米颗粒的高固有甲醇氧化活性,与商业Pt/C催化剂相比,基底材料NiFe-LDHs在200,000 s循环测试后进一步增强了Pt的抗中毒能力和稳定性。NiFe-LDHs层板上单原子分散的Fe作为锚定位点将Pt纳米颗粒均匀分散在其表面,进一步充分利用了层状金属氢氧化物表面丰富的OH基团,促进邻近Pt位点上毒化中间体的氧化去除。这项工作突出了NiFeLDH在提高甲醇氧化反应整体效率方面的特殊性,为其他甲醇氧化电催化的设计和应用提供了指导。

Active and durable electrocatalysts for methanol oxidation reaction are of critical importance to the commercial viability of direct methanol fuel cell,which has already attracted growing popularities.However,current methanol oxidation electrocatalysts fall far short of expectations and suffer from excessive use of noble metal,mediocre activity,and rapid decay.Here we report the Pt anchored on NiFe-LDHs surface hybrid for stable methanol oxidation in alkaline media.Based on the high intrinsic methanol oxidation activity of Pt nanoparticles,the substrates NiFe-LDHs further enhanced anti-poisoning ability and maintained unaffected stability after 200,000 s cycle test compared to commercial Pt/C catalyst.The use of NiFe-LDHs is believed to play the decisive role to evenly disperse Pt nanoparticles on their surface using single atomic dispersed Fe as anchoring sites,making full use of abundant OH groups and subsequent facilitating the oxidative removal of carbonaceous poison on neighboring Pt sites.This work highlights the specialty of NiFe-LDHs in improving the overall efficiency of methanol oxidation reaction.