类淀粉蛋白诱导高活性一维亚纳米(sub-1 nm) 铂基合金的合成、生长机理及电催化性能

Fuel cells are favored by industry, transportation and other fields because of their environmental efficiency. Platinum is an important catalyst for fuel cell, but the platinum reserves are low and the price is expensive. Our team has made beneficial exploration for around 2 nm platinum nanowires catalyst (JACS, 2012). More recently, scientists both at home and abroad focus on the nanometer catalyst synthesis, especially point out that surface atomic ratio is close to 100% in the material size less than 1 nm. These materials can greatly improve the catalytic performance. This project will aim to length up to micron level and less than 1 nm in diameter platinum alloy nanowires, and subnanometer (sub-1nm) platinum-based alloy shell nanowires core-shell structure, and the synthesis of subnanometer platinum-based alloy tube wall nanotubes. A one-dimensional platinum-based alloy catalyst with uniform morphology will be controlled by the stable fibrosis properties of the amyloid protein. Reducing the amount of platinum by alloying, the catalytic activity can be improved by subnanometer. The influence rule of alloy element and the synergistic effect of multivariate doping are studied. By oxygen reduction and methanol oxidation test and material composition structure characterization, we explore its growth mechanism, the control law of nanoscale electric catalytic properties. The catalysts with high activity and stability will be obtained.

燃料电池因其环保高效受到工业、交通等领域的青睐。铂是燃料电池重要的催化剂，但铂储量少且价格昂贵，提高铂基催化剂的活性和降低铂用量成为研究热点。我们课题组在2nm左右铂纳米线催化剂方面做了有益探索（JACS, 2012），最近国内外科学家聚焦亚纳米电催化剂合成，特别指出材料特征尺寸小于1nm时表面原子比例接近100%，催化性能会极大提高。本项目将致力于长度达微米级直径小于1nm的铂基合金纳米线、亚纳米(sub-1 nm)铂基合金外壳核壳结构纳米线，亚纳米管壁铂基合金纳米管的合成。利用类淀粉蛋白稳定的纤维化特性控制合成形貌均匀的一维铂基合金催化剂。通过合金化降低铂的用量，通过亚纳米化提高其催化活性。研究合金元素的影响规律以及多元掺杂时的协同效应。通过氧还原、甲醇氧化等测试及材料的组分结构等表征，探究其生长机理、亚纳米尺度电催化性能的控制规律，将催化剂的活性和稳定性提高到新高度。

铂是燃料电池重要的催化剂，但铂储量少且价格昂贵，提高铂基催化剂的活性和降低铂用量成为研究热点。. 本工作提出一种将PdAu原子层夹入一维(1D) Pd/Pt核壳纳米线(NWs)的策略，提高了亚纳米Pt壳层在ORR应用中的催化稳定性。所制备出的Pd/PdAu/Pt核/壳/壳结构纳米材料在80000个电位循环后，ORR质量活性仅下降7.80%。与在80000个电位循环后发生明显结构变形且失活的Pd/Pt核壳NWs相比，三明治核/壳纳米结构的电催化稳定性得到显著提高。. 本工作制备了一系列在酸性介质中对ORR具有良好活性的PdM (M=Fe, Co, Ni) NWs。PdNi NWs/C的E1/2 比商用Pt/C 和纯Pd NWs/C 分别正向移动了25 mV和138 mV。经过10000次循环测试后，PdM NWs/C的稳定性优于纯Pd NWs/C。. 本工作构建了双金属PdPt多孔纳米线（PdPt PNWs），然后通过选择性氧化刻蚀法设计了一种新型的Pt壳PdPt多孔纳米管（Pt壳PdPt PNTs）。质量活性和面积比活性是商用Pt/C的14.3倍和9.6倍。. 本工作合成了PdPtIr PNTs，经过30000次电位循环测试后性能几乎没有变化。电流密度为-3 mA/cm2处（氧还原）与10 mA/cm2处（析氧）表现出642 mV超低电位间隙. 本工作合成了 PtFeM（M=Rh,Ru,Ir）哑铃形纳米棒催化剂。PtFeRh 纳米棒催化剂在甲醇氧化中的质量活性和实际比活性分别为商业铂碳催化剂的 7.29 倍与 6.96 倍。. 本工作合成了PtPdM（M=Mo,Fe, Mn）空心纳米环催化剂，空心纳米环呈六边形，边缘宽度仅有 2.5 nm。PtPdMo 纳米环的氧化还原质量活性和比活性分别是商业铂碳催化剂的 9.45 倍与 8.15 倍，在长循环稳定性测试中，30000 圈后PtPdMo 纳米环催化剂质量活性仅损失12%。