Production and characterization of organic solar cells

Abstract

Purpose The study aims to carry out the production of a bulk heterojunction organic solar cell in a laboratory scale using a blend of poly (3-hexylthiopene) (P3HT) and [6, 6]-phenyl (C61) butyric acid methyl ether (PCBM). Design/methodology/approach Four inverted geometry organic solar cells were prepared based on 1:1 ratio of P3HT to PCBM and subjected to post annealing at different temperatures of 32, 120, 130 and 140°C. Solar cells were fabricated with structure glass/ITO/P3HT:PCBM/PEDOT:PSS/Au and characterized using Keithley 2400 series sourcemeter and a multimeter interfaced to a computer system with a LabVIEW software, which showed both dark and illumination current–voltage characteristic curves. Four reference cells were also fabricated with structure soda lime glass/P3HT:PCBM and annealed at different temperatures of 32, 120, 130 and 140°C. Findings The third organic solar cell prepared, Sample CITO, had the best performance with power conversion efficiency (PCE) of 2.0281 per cent, fill factor (FF) of 0.392, short circuit current of −0.0133 A and open circuit voltage of 0.389 V. Annealing of active layer was found to improve cell morphology, FF and PCE. Annealing of the active layer at 140°C resulted in a decrease of the PCE to 2.01 per cent. Research limitations/implications These findings are in good agreement with previous investigation in literature which reported that best annealing temperature for a 1:1 ratio blend of active material is 130°C. Ultraviolet–visible spectra on reference cells showed that sample CITO had wider absorption spectra with peak absorbance at a wavelength of 508 nm. Originality/value This research is purely original.

Development of a Modular and Sustainable Yam Pounding Machine

“…Yam pounding machine can be operated by electrical, mechanical and solar means. Best performance with power conversion is possible using Solar technology [1].…”

“…Yam pounding machine can be operated by electrical, mechanical and solar means. Best performance with power conversion is possible using Solar technology [1].According to the food information Network in 2008, it was estimated that the world production of yam in 1993 was at 28.1 million tons in which 96% of this estimate was from the West Africa tropical regions and 71% from Nigeria. This figure was later reviewed in 1998 accounting for about 72.4% of the world total production of 29.6million tones.…”