In this twenty-first century, energy shortages have become a global issue as energy demand is growing at an astounding rate while the energy supply from fossil fuels is depleting. Thus, the urge to develop sustainable renewable energy to replace fossil fuels is significant to prevent energy shortages. Solar energy is the most promising, accessible, renewable, clean, and sustainable substitute for fossil fuels. Third-generation (3G) emerging solar cell technologies have been popular in the research field as there are many possibilities to be explored. Among the 3G solar cell technologies, perovskite solar cells (PSCs) are the most rapidly developing technology, making them suitable for generating electricity efficiently with low production costs. However, the toxicity of Pb in organic–inorganic metal halide PSCs has inherent shortcomings, which will lead to environmental contamination and public health problems. Therefore, developing a lead-free perovskite solar cell is necessary to ensure human health and a pollution-free environment. This review paper summarized numerous types of Sn-based perovskites with important achievements in experimental-based studies to date.

Solar cells are pivotal in harnessing renewable energy for a greener and more sustainable energy landscape. Nonetheless, eco-friendly materials for solar cells have not been as extensive as conventional counterparts, highlighting a significant area for further investigation in advancing sustainable energy technologies. This study investigated natural dyes from cost-effective and environmentally friendly blueberries and mulberries. These dyes were utilized as alternative sensitizers for dye-sensitized solar cells (DSSCs). Alongside the natural dyes, a green approach was adopted for the DSSC design, encompassing TiO₂ photoanodes, eco-friendly electrolytes, and green counter-electrodes created from graphite pencils and candle soot. Consequently, the best-optimized dye sensitizer was mulberry, with an output power of 13.79 µW and 0.122 µW for outdoor and indoor environments, respectively. This study underscored the feasibility of integrating DSSCs with sensitizers derived from readily available food ingredients, potentially expanding their applications in educational kits and technology development initiatives.

Aluminium–gallium (Al–Ga) co-doped ZnO (AGZO) thin films with different Al–Ga at.% were spin coated on glass substrates using sol–gel spin coating technique. Morphological images by atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) reveal that the granular structures of co-doped films are embedded with microrods, which has never been reported before. The density of the microrods increases with higher co-doping at.%. The Hall Transport measurements reveal that the electrical properties of the co-doped films are comparable with single Ga doped ZnO films, which implies that the co-doping method can be a way forward to reduce the fabrication cost of the doped ZnO films involving expensive raw material. Also, the unique features of the AGZO films embedded with microrods may create new opportunity for these films to be implemented in emerging optoelectronic devices such as solar cells and organic light emitting diodes.