An anodic oxidation of aqueous Br- ions on platinum substrate in the presence of tetrabutylammonium (Bu4N+) ions leads to the formation of This accompanies the self-assembly of Bu4N+ cations to the electrogenerated Br- anions being accumulated near the electrode surface. The Br-3(-) deposited Br-3(-) anions can be replaced with Br in solution by ion exchange, resulting in a thin film of Bu4NBr salt with high crystallinity and low electrical conductivity. (c) 2007 Elsevier B.V. All rights reserved.