Using first-principles density functional theory calculations and ab initio molecular dynamic simulations, we propose Li10‑x SnP2S12‑x Cl x as a highly functional solid electrolyte for a Li ion battery. The underlying mechanisms of excellent Li ion conductivity and electrochemical stability are 2-fold: (i) complete replacement of expensive Ge4+ with relatively cheaper Sn4+ species and (ii) partial substitution of Cl– for S2– to form body-centered cubic anionic framework. The rationally controlled doping levels of the halide Cl atoms play a vital role to enlarge Li ion diffusion channel sizes. The unique feature of the electronic structure in Li10‑x SnP2S12‑x Cl x ensures its superior electrochemical durability in comparison to the conventional LGPS counterpart. We propose a design principle to crank up the stability even more, as high as 8 V, via forming passivating Li–Cl layers at the Li-metal anode surface. We propose Li10‑x SnP2S12‑x Cl x as a promising electrolyte material to facilitate a wide commercialization of all solid-state Li ion batteries.

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Dye-sensitized solar cells (DSCs) have been considered as promising and reliable solar energy conversion devices that are suitable for various applications. In general, mesoscopic TiO 2 films are often used as photoanodes in DSCs; however, significant effort has been put into the development of NiO photocathodes with the long-term goal of tandem DSCs for high-voltage output. In this study, we report the preparation of mesoscopic NiO films via electrochemical anodization of Ni foil and their application as photocathodes in p-type DSCs. The anodic NiO had a mesoporous structure composed of ∼10 nm nanoparticles, and to the best of our knowledge, this was the first demonstration of mesoscopic NiO synthesis by anodic oxidation. The performance of the anodic photocathodes was comparable to that of conventional NiO electrodes comprising 20 nm-sized particles, even though the preparation of the anodic oxide film was significantly easier. Additionally, charge transfer kinetics in the NiO films were compared with those in conventional photocathodes using electrochemical impedance analyses, and the feasibility of the anodic NiO photocathodes in tandem DSCs was also demonstrated.

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A solid-state electrolyte (SSE) is a key component in the performance control of all-solid-state Li-ion batteries. The development of the promising materials has been, however, come to a standstill due...