A comprehensive review on advancements and optimization strategies in dye-sensitized solar cells: Components, characterization, stability and efficiency enhancement

In 2022, primary energy consumption saw a substantial increase of 6.63 exajoules (EJ) compared to the previous year, reaching a record-high total consumption of 604.04 EJ, and is expected to surge by 28 % between 2015 and 2040. This global energy-consumption surge came with an environmental cost, as carbon dioxide emissions from various sources continued to rise. Specifically, carbon dioxide equivalent emissions from energy use, industrial processes, flaring, and methane experienced a 0.8 % increase. Solar energy is a highly promising alternative energy source. This is primarily because of its reported ability to produce an estimated 4.3 × 1020 J of energy over a single hour of sunlight exposure. Dye-sensitized solar cells (DSSCs) have become promising solar-energy candidates owing to their highly flexible solar cell design, regarding shape, color, and transparency. Synthetic dyes have high efficiency; however, they need a complex synthesis route, have high fabrication costs, and are toxic. Discovering a new, non-toxic, stable, and opto-electronically enhanced material necessitates a significant time investment, hence, natural dyes have emerged as a highly promising alternative. In this article, the state-of-the-art of NDSSCs is reviewed, including semiconductor photoanode modification, dyes, counter electrodes, and electrolyte development, for a complete understanding of the processes and parameters controlling their photovoltaic performance. Various parameters are suggested for cell efficiency enhancements. Furthermore, several strategies are comprehensively discussed for stability improvement of NDSSCs. Finally, the potential for future research into NDSSCs is discussed.