from 28 June 2015 to 3 July 2015 (Africa/Johannesburg)
Africa/Johannesburg timezone
SAIP2015 Proceeding published on 17 July 2016
Home > Timetable > Session details > Contribution details
PDF | XML | iCal

Thermal and compositional defects in dip-coated iron oxide (α-Fe2O3) thin film photoanodes: Effects on film properties

Presented by Ms. Kelebogile MAABONG on 30 Jun 2015 from 16:10 to 18:00
Type: Poster Presentation
Session: Poster1
Track: Track A - Division for Physics of Condensed Matter and Materials
Board #: A.450

Abstract

Hematite (α-Fe<sub>2</sub>O<sub>3</sub>) is an attractive semiconductor material for solar assisted electrolysis of water due to its narrow band (~ 2.1 eV), low cost and non-toxicity. α-Fe<sub>2</sub>O<sub>3</sub> thin films photoanodes were synthesized by dip coating and their properties investigated with FESEM, XRD and photocurrent density spectroscopy. Strong dependence of structural and photoelectrochemical properties on film compositions and temperature was observed. The crystallites size was observed to increase with increasing Ti doping concentration. By fixing the doping concentration at 1 mol %, the photocurrent density at water splitting potential (1.23 V vs RHE) increased from 0.006 mA/cm<sup>-2</sup> at 450 °C to 0.386 and 0.766 mA/cm<sup>-2</sup>at 500 and 550 °C respectively then decreased to 0.249 mA/cm<sup>-2</sup> at 600 °C. Subsequent annealing temperatures introduced textural and structural defects with modifications in the film properties. The films cracked with cracks averaged 50 nm. Cracks may act as collection centres for impurities diffusing out of the lattice hence act as scattering sources for photons and carriers with consequent decrease in photoresponse of the films.

Award

No

Level

N/A

Supervisor

Dr Mmantsae Diale

Paper

No

Permission

yes

Primary authors

More

Co-authors

More