Author(s)

P. Akinyemi, O. L. Ojo, O. T. Kolebaje, C. I. Abiodun

Abstract

Six flat sample plates (7.8cm×7.8cm×0.1cm) of ferritic stainless steel 430 were polished with emery papers and gamma alumina. The films of magnesium sulphide were deposited on the sample plates using an improved chemical bath deposition (CBD) method technique at 32°C to 38°C under intense solar radiation from 2.30pm to 5.00pm respectively. The thermal emittance values of the polished and coated sample plates were determined before and after deposition of films respectively using a thermocouple potentiometer. The average thermal emittance of polished samples plates is 0.180±0.01. Thermal emittance values of deposited magnesium sulphide (MgS) thin film vary from 0.146 to 0.180±0.01. Thickness of the deposited magnesium sulphide (MgS) thin films varies from 1.790 to 9.937±0.01 μm. These values compared well with those obtained for selective absorbers using other deposition techniques. The chemical bath deposition techniques could be developed for deposition of the films at different temperatures with suitable deposition time to fabricate selective surfaces for solar energy applications.

Keywords

thermal emittance, chemically deposited magnesium sulphide thin films, surface solar energy collectors, ferritic stainless steel plate