In this section
@article{Kafizas:2010:10.1016/j.aca.2010.01.022,
author = {Kafizas, A and Mills, A and Parkin, IP},
doi = {10.1016/j.aca.2010.01.022},
journal = {Analytica Chimica Acta},
pages = {69--69},
title = {A comprehensive aerosol spray method for the rapid photocatalytic grid area analysis of semiconductor photocatalyst thin films.},
url = {http://dx.doi.org/10.1016/j.aca.2010.01.022},
volume = {663},
year = {2010}
}
TY - JOUR
AB - Indicator inks, previously shown to be capable of rapidly assessing photocatalytic activity via a novel photo-reductive mechanism, were simply applied via an aerosol spray onto commercially available pieces of Activ self-cleaning glass. Ink layers could be applied with high evenness of spread, with as little deviation as 5% upon UV-visible spectroscopic assessment of 25 equally distributed positions over a 10cmx10cm glass cut. The inks were comprised of either a resazurin (Rz) or dichloroindophenol (DCIP) redox dye with a glycerol sacrificial electron donor in an aqueous hydroxyethyl cellulose (HEC) polymer media. The photo-reduction reaction under UVA light of a single spot was monitored by UV-vis spectroscopy and digital images attained from a flat-bed scanner in tandem for both inks. The photo-reduction of Rz ink underwent a two-step kinetic process, whereby the blue redox dye was initially reduced to a pink intermediate resorufin (Rf) and subsequently reduced to a bleached form of the dye. In contrast, a simple one-step kinetic process was observed for the reduction of the light blue redox dye DCIP to its bleached intermediates. Changes in red-green-blue colour extracted from digital images of the inks were inversely proportional to the changes seen at corresponding wavelengths via UV-visible absorption spectroscopy and wholly indicative of the reaction kinetics. The photocatalytic activity areas of cuts of Activ glass, 10cmx10cm in size, were assessed using both Rz and DCIP indicator inks evenly sprayed over the films; firstly using UVA lamp light to activate the underlying Activ film (1.75mWcm(-2)) and secondly under solar conditions (2.06+/-0.14mWcm(-2)). The photo-reduction reactions were monitored solely by flat-bed digital scanning. Red-green-blue values of a generated 14x14 grid (196 positions) that covered the entire area of each film image were extracted using a custom-built program entitled RGB Extractor(C). A homogenous degradation over the 196 positi
AU - Kafizas,A
AU - Mills,A
AU - Parkin,IP
DO - 10.1016/j.aca.2010.01.022
EP - 69
PY - 2010///
SN - 1873-4324
SP - 69
TI - A comprehensive aerosol spray method for the rapid photocatalytic grid area analysis of semiconductor photocatalyst thin films.
T2 - Analytica Chimica Acta
UR - http://dx.doi.org/10.1016/j.aca.2010.01.022
VL - 663
ER -
Dr. Andreas Kafizas
Leader - Solar Coatings Group
e-mail: a.kafizas@imperial.ac.uk
tel: +44(0)20 7594 6752
twitter: @CoatingsSolar