Hu Tingting, Chen Weiheng, Liu Yubing, Gong Longxiang, Jiang Zhongqing, Bhalothia Dinesh, Maiyalagan Thandavarayan, Jiang Zhong-Jie
Key Laboratory of Optical Field Manipulation of Zhejiang Province, Department of Physics, Zhejiang Sci-Tech University, Hangzhou, 310018, P. R. China.
Department of Mechanical Engineering, Ningbo University of Technology, Ningbo, 315336, P. R. China.
Small. 2023 Nov;19(46):e2304076. doi: 10.1002/smll.202304076. Epub 2023 Jul 18.
Plasma treatment and reduction are used to synthesize Pt nanoparticles (NPs) on nitrogen-doped carbon nanotubes (p-Pt/p-NCNT) with a low Pt content. In particular, the plasma treatment is used to treat the NCNT to give it with more surface defects, facilitating a better growth of the Pt NPs, while the plasma reduction produces the Pt NPs with a reduced fraction of the surface atoms at the high oxidation states, increasing the catalytic activities of the p-Pt@p-NCNT. Even at the low Pt content (7.8 wt.%), the p-Pt@p-NCNT shows superior catalytic activities and good stabilities for methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR). The density functional theory (DFT) calculations indicate that the defects generated in the plasma treatment can help the growth of the Pt NPs on the NCNTs, leading to the stronger electronic coupling between Pt and NCNT and the increased stability of the catalyst. The plasma reduction can give the Pt NPs with optimized surface oxidation states, decreasing the energy barriers of the rate-determining steps for MOR and ORR. When used as the anode and cathode catalysts for the direct methanol fuel cells (DMFCs), the p-Pt@p-NCNT exhibits a higher maximum power density of 81.9 mW cm at 80 °C and shows good durability.
采用等离子体处理和还原的方法，在氮掺杂碳纳米管（p-Pt/p-NCNT）上合成了低Pt含量的Pt纳米颗粒（NPs）。具体而言，等离子体处理用于处理NCNT，使其具有更多的表面缺陷，从而有利于Pt NPs更好地生长；而等离子体还原则产生表面处于高氧化态的原子比例降低的Pt NPs，提高了p-Pt@p-NCNT的催化活性。即使在低Pt含量（7.8 wt.%）下，p-Pt@p-NCNT对甲醇氧化反应（MOR）和氧还原反应（ORR）仍表现出优异的催化活性和良好的稳定性。密度泛函理论（DFT）计算表明，等离子体处理产生的缺陷有助于Pt NPs在NCNTs上生长，导致Pt与NCNT之间更强的电子耦合以及催化剂稳定性的提高。等离子体还原可以使Pt NPs具有优化的表面氧化态，降低MOR和ORR速率决定步骤的能垒。当用作直接甲醇燃料电池（DMFCs）的阳极和阴极催化剂时，p-Pt@p-NCNT在80°C时表现出81.9 mW cm 的更高最大功率密度，并具有良好的耐久性。
