Assembly of Dye-Sensitized Solar Cell using the Stem and Grain of Sorghum Bicolor as Sensitizers

Abstract

Red anthocyanins from sample A (stem of sorghum bicolor) and sample B (grains of sorghum bicolor) were employed as TiO₂ dye – sensitizers. Solar cells sensitized by the extracts of sample A achieved the following for outdoor measurement; I_SC = 0.0023mA/cm², V_{OC =} 0.0022V,

P_max = 3.666mV/cm², FF = 0.7212, ?= 1.7554 and for sample B outdoor measurement   FF = 0.7961, I_sc = 0.00178mA/cm², V_oc = 0.0014V, P_max = 4.96 x 10^-6mw/cm² and ? = 4.221 under the illumination of solar energy 4.7x10^-3 W/cm² respectively. The indoor measurement values for the same dyes sensitized cells determined for sample A are I_SC=0.0182mA/cm², V_OC = 0.004 V;

P_max = 3.299 x 10^-7 mW/cm², FF = 0.4512, ? =0.15 and sample B achieved I_SC = 0.01378 mA/cm²; V_OC = 0.005 V, P_max = 3.5 x 10^-7 mW/cm², FF = 0.5511and ? =0.18 respectively.

The results show that Sample B (indoor and outdoor measurement) has higher efficiency than sample A. This is due to the constituent of the extract .Sample A and B show a successful conversion of visible light into electricity by using natural dyes as band-gap semiconductor sensitizer in dye-sensitized solar cells .This can be use in large scale to reduce power and energy requirements for future industry designs.

Key Word: Sorghum Bicolor, Dye-sensitized solar cell, Solar light energy conversion, TiO₂