Development of coal based low dimensional nanocarbon for enhancing the performance of DSSC

Abstract

Dye-sensitized solar cells are viable third-generation photovoltaic cells capable of meeting the future energy demand in an environmentally friendly manner. However, newlineto harness the incident solar energy, the bottlenecks faced by dye-sensitized solar cells are interfacial charge recombination and narrow absorption region. These problems can be appreciably solved by using low-dimensional nanocarbons due to their optoelectronic property. Further, improving the light trapping abilities is a facile route for increasing the solar cells efficiency, which could be achieved using low-dimensional nanocarbon as a co-sensitizer. In addition, their ability to utilize the ultraviolet region of the solar spectrum along with their emission property in the visible region aids in harnessing the incident light effectively. This dissertation focuses on synthesizing low-dimensional nanocarbons from the carbonaceous precursor - Coal and utilize its characteristics to improve the DSSCs performance. Notably, coal-derived low-dimensional nanostructures are preferred over inorganic quantum dots because of their ease of production, low toxicity, and environmental friendliness. This work employed coal of different ranks, such as lignite and anthracite, as the low-dimensional nanocarbon precursors. The nanocarbons were prepared using simple and facile techniques, and their morphological and optical properties were characterized using transmission electron microscopy, UV-Visible, and photoluminescence spectrophotometers. The inclusion of nanocarbons into the DSSC system showed an appreciable improvement in their efficiency. When measuring the fabricated DSSCs under standard conditions, the lignite-derived nanocarbons showed a maximum efficiency of 9.02 % when utilized as a co-sensitizer with the conventional N719 sensitizer. Further, when utilized as a co-active layer, the DSSC exhibited an efficiency of 9.07 %, outperforming the pristine device s efficiency.