THE DEVELOPMENT OF FACETING AND ROUGHENING AT PLATINUM POLYFACETED SINGLE-CRYSTAL ELECTRODES IN A CHLOROPLATINIC ACID-SOLUTION

The description of a procedure for producing preferred crystallographic orientation and roughness development at Pt single-crystal microspheres is the main topic of this paper. It is based on the application of a repetitive square-wave-potential routine to Pt microsphere electrodes in chloroplatinic acid solution. The operation conditions can be adjusted to assure that the Pt electrodeposition and the Pt electrodissolution are the main reactions taking place at the cathodic and anodic half-cycle of the periodic potential routine, respectively. Surface oxide formation on Pt can be largely avoided in the complex-ion-forming solution. Depending on the characteristics of the potential routine different Pt surface textures with specific reactivities for the H-adatom electrosorption processes can be obtained. The procedure discussed in this work can be extended to the preparation of dispersed Pt electrodes with a defined morphology.