Division of Physics, Mathematics & Astronomy, California Institute of Technology, Pasadena, California 91125, USA.
ACS Nano. 2013 Jun 25;7(6):4919-23. doi: 10.1021/nn400156y. Epub 2013 Jun 11.
We present a method for forming ordered rhodium nanostructures on a solid support. The approach makes use of a block copolymer to create and assemble rhodium chloride nanoparticles from solution onto a surface; subsequent plasma and thermal processing are employed to remove the polymer and fully convert the nanostructures to metallic rhodium. Films cast from a solution of the triblock copolymer poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) dissolved in toluene with rhodium(III) chloride hydrate were capable of producing a monolayer of rhodium nanoparticles of uniform size and interparticle spacing. The nanostructures were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. The electrocatalytic performance of the nanoparticles was investigated with AC impedance spectroscopy. We observed that the addition of the particles to a model solid oxide fuel cell anode provided up to a 14-fold improvement in the anode activity as evidenced by a decrease in the AC impedance resistance. Examination of the anode after electrochemical measurement revealed that the basic morphology and distribution of the particles were preserved.
我们提出了一种在固体载体上形成有序铑纳米结构的方法。该方法利用嵌段共聚物从溶液中将氯化铑纳米颗粒组装到表面上；随后采用等离子体和热处理去除聚合物并将纳米结构完全转化为金属铑。将三嵌段共聚物聚（苯乙烯-b-2-乙烯基吡啶-b-氧化乙烯）溶解在甲苯中的溶液浇铸而成的薄膜与水合三氯化铑混合，可以制备出单层的具有均匀尺寸和颗粒间间距的铑纳米颗粒。通过扫描电子显微镜、X 射线光电子能谱和原子力显微镜对纳米结构进行了表征。通过交流阻抗谱研究了纳米颗粒的电催化性能。我们观察到，将这些颗粒添加到模型固体氧化物燃料电池阳极中，可使阳极活性提高多达 14 倍，这可以通过交流阻抗电阻的降低来证明。电化学测量后对阳极的检查表明，颗粒的基本形态和分布得以保留。
