Global energy demand keeps increasing unprecedentedly with rapid industrial development and population growth, resulting in ever-increasing reliance on fossil fuels and intensifying environmental degradation. Solar energy is the most abundant and environmentally benign renewable energy source; hence, photovoltaics plays an indispensable role in the pursuit of sustainability in the future. Among various emerging photovoltaic technologies, Dye-Sensitized Solar Cells (DSSCs) have been known for their low production cost, environmental compatibility, and better performance in low-intensity and diffused lighting conditions. DSSCs operate based on the photosensitization of a wide band-gap semiconductor, typically TiO2, allowing efficient electron injection and charge transport. This review discusses the basic structure, operational mechanism, and materials engineering of key components of DSSCs, including photoanodes, sensitizers, electrolytes, and counter electrodes, and highlights recent efforts to improve efficiency and long-term stability. Advances in nanostructured TiO2, dye molecular design, quasi-solid electrolytes, and platinum-free electrocatalysts significantly enhance the commercial prospect of DSSCs. Theoretical approaches, such as DFT and TD-DFT, further facilitate the rational design of DSSCs materials by predicting electronic transitions and interfacial charge behavior. Overall, DSSCs remain a promising alternative for clean power generation, particularly in portable, indoor, and building-integrated applications.
Kumar et al. (Sun,) studied this question.