@article {4080,
	title = {Exceeding 30\% efficiency for an environment-friendly tandem solar cell based on earth-abundant Se/CZTS materials, ISSN / e-ISSN 1386-9477 / 1873-1759},
	journal = {Physica E: Low-dimensional Systems and Nanostructures },
	volume = {Volume 109},
	year = {2019},
	pages = {pp 52-58},
	abstract = {In this paper, a new\&nbsp;Se/CZTSSe\&nbsp;tandem solar cell architecture is proposed as a viable approach to reach ultrahigh efficiency values at low fabrication cost. The proposed tandem design consists of a\&nbsp;Se-based top cell with\&nbsp;Ti\&nbsp;intermediate ultra-thin metallic layers (MLs) and a\&nbsp;CZTS\&nbsp;bottom cell with graded band-gap aspect. The role of the introduced design amendments in achieving the dual-benefit of enhanced optical behavior and reduced recombination losses is investigated by means of an accurate numerical modeling. Moreover, a comprehensive study which involves the impact of design parameters such as the\&nbsp;MLs\&nbsp;position and the\&nbsp;CZTSSe\&nbsp;band-gap profile on the device performance is carried out. Moreover, Particle Swarm Optimization (PSO)-based metaheuristic technique is used to boost up the\&nbsp;Se/CZTSSe\&nbsp;tandem cell efficiency by identifying both the suitable position of the introduced ultrathin\&nbsp;MLs\&nbsp;and the appropriate\&nbsp;CZTSSe\&nbsp;band-gap profile. It is found that the adopted optimization approach pinpoints a new path toward achieving over 30\% efficiency, not only it provides the possibility to reduce interface recombination effects by optimizing the band offset at the buffer/absorber interfaces but also enables selecting the most favorable design configuration associated with enhanced optical behavior. This makes the optimized\&nbsp;Se/CZTSSe\&nbsp;tandem solar cell potential alternative for providing high-efficiency and stable tandem solar cell.},
	url = {https://www.sciencedirect.com/science/article/pii/S1386947718317144},
	author = {Ferhati Hichem and Djeffal Fay{\c c}al}
}
