CAREER: Morphological Control and Applications of Nanoporous Gold

这项资助着眼于纳米多孔金（NPG）的形成机制、粗化行为和应用。NPG是通过将金/银合金中的银溶解在酸中形成的，这是一个合金化过程，留下的是一个几乎纯金的开放海绵。通过改变实验条件，如预合金成分和后脱合金退火时间，海绵状韧带的尺寸可以在5纳米到许多微米的长度范围内进行调节。在本研究中，NPG是研究纳米尺度表面动力学的模型系统。采用电子束蒸发法制备NPG薄膜，并利用SEM和TEM对其孔隙度随时间的变化进行表征。将检查粗化行为，以测量表面扩散率作为化学环境的函数。该研究包括改进通用原子模拟程序。NPG在高表面开放结构具有优势的应用中具有很大的前景，例如传感器和电极。一个简单的MEMS氢燃料电池将建立在涂有铂催化剂的NPG作为电极

0092756Erlebacher This grant looks at the formation mechanism, coarsening behavior, and applications of nanoporous gold (NPG). NPG is formed by dissolving silver from gold/silver alloys in acid, a dealloying process that leaves behind an open sponge of nearly pure gold. By varying the experimental conditions such as the pre-alloyed composition and post-dealloying annealing time, the size of the spongy ligaments is tunable over length scales from 5 nm to many microns. For this research NPG is a model system for studying nanoscale surface kinetics. NPG films will be grown by electron beam evaporation, and the time evolution of the porosity will be characterized by SEM and TEM. Coarsening behavior will be examined to measure surface diffusivity as a function of chemical environment. The research includes refinement of a general-purpose atomistic simulation program.%%%NPG holds great promise in applications where high surface open structures are advantageous, e.g. sensors and electrodes. A simple MEMS hydrogen fuel cell will be built with NPG coated with platinum catalyst as the electrodes.***