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This work investigates the effect of band structure, optical spectra, computed elastic coefficients, Bulk-to-Shear modulus ratio, Young’s modulus and Poisson’s ratio in metal selenide compounds and their influence on electronic, optical, and elastic properties of bulk crystals using density functional theory (DFT). By studying the structural and geometrical parameters, we show that the V–VI group compound has a direct bandgap of 0.887eV and the band structure can be explained by a partial density of states (PDOS) plot. By using Pugh’s formation, the bulk-to-shear ratio can be significant in precisely determining the ductility of a material. Poisson’s ratio can provide information to examine whether the lattice crystal is ionic or covalent. Our elastic data show that the orthorhombic system is found to be unstable. The optical spectra (high absorption coefficient of $1.78\times 10^5$cm${}^{-1}$, dielectric coefficient of 8.61 and reflective index of 2.93) of our current work would be beneficial to explore the applications of optoelectronic devices, especially in light-harvesting materials, covering the UV region. Our findings advance the knowledge of the structural, electronic, optical, vibrational, and mechanical properties of Sb₂Se₃, the key to their use, and explained the potential applications in photovoltaics perspectives.

Both experimental and theoretical works have demonstrated that two-dimensional materials exhibit strong thickness-dependent electronic and linear optical properties. However, the nonlinear optical (NLO) effect with respect to the thickness still needs to be further investigated, which is of great significance to design different photonic devices. Herein, we develop the physical vapor deposition technique to prepare a series of antimony selenide (Sb₂Se${}_3)$ films. The relationship between the thickness of Sb₂Se₃ film and the NLO absorption was investigated by a $Z$-scan system under 35fs, 800nm laser excitation. The result shows the thicker Sb₂Se₃ film ($\sim$50nm) performs a larger third-order NLO susceptibility (Im${\chi }^{(3)})$ approximately $-4.59\times 10^{-8}$ esu, which can be interpreted by the stronger photon absorption, lower saturable intensity, and larger absorption cross-section of ground-state. More importantly, the Im${\chi }^{(3)}$ absolute value of thick Sb₂Se₃ film is also far larger than those of graphene, black phosphorus, transition metal dichalcogenide, MXenes, and heterostructure. This work demonstrates that Sb₂Se₃ film is an excellent saturable absorber and provides a promising application in nonlinear photonics.

A nanocomposite consisting of rod-like Sb₂Se₃ and fiberous palygorskite (Pal) was prepared using cetyltrimethyl ammonium bromide (CTAB) as a pillaring agent to change Pal microstructure. CTAB optimal dosage was 0.2g (versus 0.388g of Pal). Sb₂Se₃/Pal has a high catalytic activity towards the catalytic reduction of $p$-nitrophenol to $p$-aminophenol while in the presence of NaBH₄ at room temperature. The excellent performance is attributed to dispersion of rod-like Sb₂Se₃ in fiberous Pal which promoted more active sites exposure. The results provide new ideas for preparing new catalysts.

Antimony Selenide (Sb₂Se₃) exhibits potential as a solar energy material owing to its optimal bandgap, lack of toxicity, and abundance of earth abundant elements. Currently, cadmium sulfide (CdS) serves as the predominant buffer layer for Sb₂Se₃ solar cells. However, the use of CdS hinders environmentally friendly advancement due to the toxic properties of the element cadmium. Hence, the quest for non-toxic buffer layers poses a significant challenge to the further advancement of Sb₂Se₃ solar cells. In prior research, tin oxide (SnO₂) has been explored as a buffer layer. Nonetheless, the efficiency of SnO₂/Sb₂Se₃ solar cells was hampered by the rough surface of SnO₂ films and the poor crystallinity of Sb₂Se₃ films. In this investigation, we enhanced device efficiency by improving the uniformity of the SnO₂ surface and enhancing the crystallinity of Sb₂Se₃ through spin-coating sulfur (S) onto the SnO₂ film. Detailed examinations were conducted on the structure, optical, and electrical properties of the respective SnO₂ and Sb₂Se₃ thin films. Ultimately, an efficiency of 3.38% was achieved using the spin-coated S:SnO₂ film, marking an 85% enhancement compared to the baseline device.

Antimony selenide is a promising semiconductor with great application potential in the fields of optoelectronic devices. In this work, the vapor transport deposition (VTD) method is employed to prepare Sb₂Se₃ films on substrates. The influence of deposition temperature, distance between the Sb₂Se₃ sources and substrate, and the deposition holding time on the film morphology is investigated in detail. The deposited Sb₂Se₃ thin film is employed to fabricate photodetector with a structure of ITO/SnO₂/Sb₂Se₃/Au, where the spin-coated SnO₂ film is used as the buffer layer. The device demonstrates relative high responsivity in the range of 300–1000nm with a maximum value of 312mA W${}^{-1}$ at 750nm.