Electrochemically Induced Mesomorphism Switching in a Chlorpromazine Hydrochloride Lyotropic Liquid Crystal.

The discovery of electrochemical switching of the L phase of chlorpromazine hydrochloride in water is reported. The phase is characterized using polarizing microscopy, X-ray scattering, rheological measurements, and microelectrode voltammetry. Fast, heterogeneous oxidation of the lyotropic liquid crystal is shown to cause a phase change resulting from the disordering of the structural order in a stepwise process.

Surface redox chemistry and mechanochemistry of insulating polystyrene nanospheres.

Cyclic voltammetry (CV) of polystyrene nanospheres was carried out after immobilisation onto boron-doped diamond electrodes. Although the polystyrene is insulating, a voltammetric response was obtained. This was attributed to the high surface area of the nanospheres, allowing the redox chemistry of the polystyrene surface to be probed despite the non-conducting nature of the bulk.

Nanodiamond surface redox chemistry: influence of physicochemical properties on catalytic processes.

Modification of an electrode with an immobilised layer of nanodiamond is found to significantly enhance the recorded currents for reversible oxidation of ferrocene methanol (FcMeOH). Current enhancement is related to nanodiamond diameter, with enhancement increasing in the order 1000 nm < 250 nm < 100 nm < 10 nm < 5 nm. We attribute the current enhancement to two catalytic processes: i) electron transfer between the solution redox species and redox-active groups on the nanodiamond surface; ii) electron transfer mediated by FcMeOH(+) adsorbed onto the nanodiamond surface.

Electrochromic and colorimetric properties of nickel(II) oxide thin films prepared by aerosol-assisted chemical vapor deposition.

Aerosol-assisted chemical vapor deposition (AACVD) was used for the first time in the preparation of thin-film electrochromic nickel(II) oxide (NiO). The as-deposited films were cubic NiO, with an octahedral-like grain structure, and an optical band gap that decreased from 3.61 to 3.

Beyond the Butler-Volmer equation. Curved Tafel slopes from steady-state current-voltage curves.

We report the discovery and analysis of curved Tafel slopes from the electrochemical reduction of hexamminecobalt(III) under steady-state conditions. In order to confirm the existence of the curvature, random assemblies of carbon microelectrodes (RAM™ electrodes) were employed to obtain experimental data over more than three orders of magnitude, without significant double layer charging currents and without ohmic distortion. Since the rate-determining step in the reduction reaction is electron transfer, and no ligand substitution reactions occur on the timescale of experiments, the curvature of the Tafel plot is attributed to the dependence of the symmetry factor on electrode potential.