Improving the activity and durability of Pd or Pt nanoparticle (NP) electrocatalyst is an urgent issue for the widespread use of fuel cells. In order to achieve high catalytic activity, incorporation of metal oxides into electrocatalysts has been pursued, mainly for the purpose of enabling strong metal-support interaction (SMSI) between the NPs and metal oxides. In this study, we demonstrate a novel method to coat TiO₂ on carbon nanotubes (CNTs) through sonochemical reaction of TiO(acac)₂ (acac = acetyl acetate) in dimethyl sulfoxide (DMSO). The TiO₂-coated CNT (TC(S)) is characterized by a continuous conformal TiO₂-coating with the thickness of ∼1.5 nm throughout without any exposed CNT surface. The same reaction in ethylene glycol (EG) or N, N-dimethylformamide (DMF) also produced TCs (TC(E) and TC(F), respectively), but without the conformity and/or continuity seen in TC(S). Formation of Pd NPs on TC by a second sonochemical reaction in EG results in Pd/TC electrocatalysts with significantly increased activity and durability for formic acid oxidation reaction (FAOR) from the reference Pd NPs on CNT. Pd/TC(S) shows the highest activity and durability, surpassing all in the literature data. The enhanced FAOR activity of Pd/TC(S) can be attributed to the SMSI effect from the interface between Pd NPs and TiO₂-coating plus the bifunctional mechanism of TiO₂. The increased durability can be explained as the result of protecting CNT against the corrosion from CNT-Pd contact.

对于燃料电池的广泛使用而言，提高Pd或Pt纳米颗粒（NP）电催化剂的活性和耐久性是迫在眉睫的问题。为了实现高催化活性，已经将金属氧化物掺入电催化剂中，主要是为了实现NP与金属氧化物之间的强金属-载体相互作用（SMSI）。在这项研究中，我们演示了一种通过在二甲亚砜（DMSO）中进行TiO（acac）₂（acac =乙酰乙酸乙酸酯）的声化学反应在碳纳米管（CNTs）上涂覆TiO ₂的新方法。TiO ₂涂层的CNT（TC（S））的特征是连续的保形TiO ₂-整个涂层厚度约为1.5 nm，没有任何暴露的CNT表面。在乙二醇（EG）或N，N-二甲基甲酰胺（DMF）中的相同反应也产生了TC（分别为TC（E）和TC（F）），但没有TC（S）中的一致性和/或连续性。在EG中通过第二次声化学反应在TC上形成Pd NPs导致Pd / TC电催化剂与甲酸在CNT上的参考Pd NPs相比，对甲酸氧化反应（FAOR）具有显着提高的活性和耐久性。Pd / TC（S）具有最高的活性和耐久性，超过了文献数据。的Pd / TC（S）的增强的活性FAOR可以归因于选自Pd纳米颗粒和TiO之间的界面SMSI效应₂ -涂敷TiO 2的双功能机理加₂。可以通过保护CNT免受CNT-Pd接触的腐蚀的结果来解释增加的耐久性。