Cubic Li₂SnS₃ emerges as a noteworthy ionic conductor and a viable electrode material for lithium secondary batteries. Its application extends to solar cell technologies, owing to its commendable optoelectronic properties and high-power conversion efficiency. In this study, we present density functional theory (DFT)-based first principles calculations for Li₂SnS_3-xSe_x (x = 0, 4, and 8% (atomic percent (at.%)) utilizing the modified Becke Johnson (mBJ) approximations, proposing a compelling alternative. Our investigation reveals significant optical absorption in the ultraviolet region for Li₂SnS_3-xSe_x (x = 0, 4, and 8%), accompanied by modest effective mass and indirect band gaps of 2.18 eV for the pristine material. Conversely, doped materials exhibit direct band gaps, with values of 2.113 eV for 4% and 2.026 eV for 8%. Furthermore, the calculated thermoelectric power factor underscores the potential and efficacy of Li₂SnS_3-xSe_x in thermoelectric energy devices. The findings not only highlight the material’s promise for solar applications but also underscore its candidacy as a novel solid-state electrolyte for lithium-ion batteries. This stems from its robust thermal stability and notable lithium-ion conductivity, positioning Li₂SnS₃ as a compelling candidate for advanced energy storage technologies.

中文翻译：

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DFT 与玻尔兹曼输运理论相结合，用于 Se (4 & 8 (at.%)) 掺杂 Li2SnS3 的光电和热电特性研究

立方Li ₂ SnS ₃成为一种值得注意的离子导体和锂二次电池的可行电极材料。由于其值得称赞的光电特性和高功率转换效率，其应用扩展到太阳能电池技术。在本研究中，我们利用改进的 Becke Johnson 提出基于密度泛函理论 (DFT) 的 Li ₂ SnS _3-x Se _x (x = 0、4 和 8%（原子百分比 (at.%)）的第一原理计算(mBJ) 近似，提出了一个令人信服的替代方案，我们的研究表明 Li ₂ SnS _3-x Se _x (x = 0、4 和 8%) 在紫外区域具有显着的光学吸收，并伴有适度的有效质量和间接带隙。相反，掺杂材料的直接带隙为 2.113 eV（4%）和 2.026 eV（8%）。此外，计算出的热电功率因数强调了 Li ₂ SnS _{3-的潜力和功效。这些发现不仅强调了}该材料在太阳能应用中的前景，而且还强调了其作为锂离子电池新型固态电解质的候选资格，这源于其强大的热稳定性和显着的锂离子电导率_。，将 Li ₂ SnS ₃定位为先进储能技术的有力候选者。