Preparation and Qualification of Single Crystals

Clavilier method for crystal preparation and flame annealing has been improved since 1980 and is employed as a standard procedure for singlecrystal electrode experiments using Pt, Pt metals, and Au. 

Clavilier s currently recommended procedure is as follows. Two cooling processes of the crystal after flame-annealing treatment are carried out between steps (a) and (b) in Fig. 1 i.e., air cooling until the temperature of the crystal becomes 200-300°C and cooling in pure water under an H2 -I- Ar stream. The transfer of the crystal into the cell in step (c) of Fig. 1 with a droplet of H2 + Ar-saturated pure water on the crystal face is important for protecting the crystal surface from impurities in air. Then the crystal surface is exposed to the solution by the dipping method of Fig. 1. 

and Pb single crystals were employed as electrodes and their surface characteristics reviewed by Hamelin. Among them, Ag single crystals were mostly investigated, as found in Refs. 35 and 36, in addition to Ref. 2. 

---