Investigation of Vacancy-Ordered Double Perovskite Halides A2Sn1−xTixY6 (A = K, Rb, Cs; Y = Cl, Br, I): Promising Materials for Photovoltaic Applications

Abstract

In the present study, the structural, mechanical, electronic and optical properties of all-inorganic vacancy-ordered double perovskites A2Sn1−xTixY6 (A = K, Rb, Cs; Y = Cl, Br, I) are explored by density functional theory. The structural and thermodynamic stabilities are confirmed by the tolerance factor and negative formation energy. Moreover, by doping Ti ions into vacancy-ordered double perovskite A2SnY6, the effect of Ti doping on the electronic and optical properties was investigated in detail. Then, according to the requirement of practical applications in photovoltaics, the optimal concentration of Ti ions and the most suitable halide element are determined to screen the right compositions. In addition, the mechanical, electronic and optical properties of the selected compositions are discussed, exhibiting the maximum optical absorption both in the visible and ultraviolet energy ranges; thus, the selected compositions can be considered as promising materials for application in solar photovoltaics. The results suggest a great potential of A2Sn1−xTixY6 (A = K, Rb, Cs; Y = Cl, Br, I) for further theoretical research as well as experimental research on the photovoltaic performance of stable and toxic-free perovskite solar cells.

Phase Separation of Br-Doped CsPbI3: A Combined Cluster Expansion, Monte Carlo, and DFT Study

“…Dong et al reported on the geometrical, electronic, and optical properties of double-perovskite material Cs 2 NaMX 6 (M = In, Tl, Sb, Bi; X = Cl, Br, I) using the first-principles calculations to investigate the halogen anions and metal anions affecting the properties [ 26 ]. The structural, opto-electronic, and mechanical properties of all-inorganic vacancy-ordered double-perovskite A 2 Sn 1−x Ti x Y 6 (A = K, Rb, Cs; Y = Cl, Br, I) were investigated using DFT, as reported by Chen et al [ 27 ]. The band structure and optical absorption results demonstrated that all A 2 Sn 1−x Ti x Br 6 (A = K, Rb, Cs) materials are semiconductors with band gaps between 0.9–1.6 eV, and A 2 TiBr 6 (A = K, Rb, Cs) compounds have the highest optical absorption both in the visible and ultraviolet regions, making them excellent materials for photovoltaic applications.…”

Editorial of the Special Issue ‘Nano-Optics and Nano-Optoelectronics: Challenges and Future Trends’

“…To explore the latest developments and challenges and the future trends in nano-optics and nano-optoelectronics, this Special Issue compiles sixteen papers dedicated to very recent advances in nanostructures and nanomaterials. In these papers, novel nanostructures and nanomaterials, such as metastructures [ 1 , 2 , 3 ], metalenses [ 4 , 5 ], nanoparticles [ 6 , 7 ], layered 2D materials [ 8 , 9 ], and nano-semiconductors [ 10 , 11 ], are presented in detail. Due to their exceptional properties, these nanostructures/nanomaterials offer a diverse range of novel applications in photodetectors [ 1 , 9 , 11 ], solar cells [ 2 , 9 , 10 ], modulators [ 1 , 3 , 8 ], light emitters [ 1 , 7 ], optoelectronic integration [ 5 , 6 ], super-resolved imaging [ 4 , 5 ], nanofabrication [ 4 ], etc.…”

“…In these papers, novel nanostructures and nanomaterials, such as metastructures [ 1 , 2 , 3 ], metalenses [ 4 , 5 ], nanoparticles [ 6 , 7 ], layered 2D materials [ 8 , 9 ], and nano-semiconductors [ 10 , 11 ], are presented in detail. Due to their exceptional properties, these nanostructures/nanomaterials offer a diverse range of novel applications in photodetectors [ 1 , 9 , 11 ], solar cells [ 2 , 9 , 10 ], modulators [ 1 , 3 , 8 ], light emitters [ 1 , 7 ], optoelectronic integration [ 5 , 6 ], super-resolved imaging [ 4 , 5 ], nanofabrication [ 4 ], etc. This Special Issue also encompasses the latest advancements in practical nano-optical and nano-optoelectronic technologies, such as femtosecond laser nano-processing [ 12 ], atomic layer coating [ 13 ], and new designs for photonic integration engineering [ 14 ].…”

“…Semiconductors have long played important roles in nano-optics and nano-optoelectronics, and extended studies would be helpful to optimizing the function of semiconductors. Chen et al [ 10 ] introduced Ti ions into an A 2 SnY 6 double-perovskite structure with quantum dots (QDs). The utilization of perovskite QDs holds significant promise for developing light sources suitable for underwater optical wireless communication systems.…”