Molybdenum trioxide (MoO₃) is an attractive semiconductor. Thus, bandgap engineering toward photoelectronic applications is appealing yet not well studied. Here, we report the incorporation of sulfur atoms into MoO₃, using sulfur powder as a source of sulfur, via a self-developed hydrothermal synthesis approach. The formation of Mo-S bonds in the MoO₃ material with the synergistic effect of sulfur doping and oxygen vacancies (designated as S-MoO_3−x) is confirmed using Fourier-transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR). The bandgap is tuned from 2.68 eV to 2.57 eV upon sulfur doping, as confirmed by UV-VIS DRS spectra. Some MoS₂ phase is identified with sulfur doping by referring to the photoluminescence (PL) spectra and electrochemical impedance spectroscopy (EIS), allowing significantly improved charge carrier separation and electron transfer efficiency. Therefore, the as-prepared S-MoO_3−x delivers a sensitive photocurrent response and splendid cycling stability. This study on the synergistic effect of sulfur doping and oxygen vacancies provides key insights into the impact of doping strategies on MoO₃ performance, paving new pathways for its optimization and development in relevant fields.

The wide utilization of lithium-ion batteries (LIBs) prompts extensive research on the anode materials with large capacity and excellent stability. Despite the attractive electrochemical properties of pure Si anodes outperforming other Si-based materials, its unsafety caused by huge volumetric expansion is commonly admitted. Silicon monoxide (SiO) anode is advantageous in mild volume fluctuation, and would be a proper alternative if the low initial columbic efficiency and conductivity can be ameliorated. Herein, a hybrid structure composed of active material SiO particles and carbon nanofibers (SiO/CNFs) is proposed as a solution. CNFs, through electrospun processes, serve as a conductive skeleton for SiO nanoparticles and enable SiO nanoparticles to be uniformly embedded in. As a result, the SiO/CNF electrochemical performance reaches a peak at 20% the mass ratio of SiO, where the retention rate reaches 73.9% after 400 cycles at a current density of 100 mA g⁻¹, and the discharge capacity after stabilization and 100 cycles are 1.47 and 1.84 times higher than that of pure SiO, respectively. A fast lithium-ion transport rate during cycling is also demonstrated as the corresponding diffusion coefficient of the SiO/CNF reaches ~8 × 10⁻¹⁵ cm² s⁻¹. This SiO/CNF hybrid structure provides a flexible and cost-effective solution for LIBs and sheds light on alternative anode choices for industrial battery assembly.

Lithium cobalt oxide (LiCoO₂) is a widely used cathode material whose mechanical behavior under pressure is increasingly relevant to cell manufacturing and extreme-environment applications. Yet a coordinated understanding of how hydrostatic pressure simultaneously affects its structural, elastic, and vibrational properties has been lacking. Here, we employ first-principles DFT-GGA-PBE calculations to investigate the structure, elastic constants and moduli, and phonon band structure of $R\overline{3}m$ LiCoO₂ under hydrostatic pressure from 0 to 50 GPa. The in-plane and interlayer lattice parameters contract anisotropically, with the c-axis showing greater compliance; our computed $c/a$ evolution reproduces the experimentally observed decreasing trend, lying systematically ∼2% below the convergent experimental datasets over the experimentally covered pressure range, with the deviation narrowing toward the highest experimentally covered pressures. All six independent pressure-corrected elastic constants increase monotonically and satisfy the Born stability criteria over the full pressure range. The polycrystalline bulk modulus more than doubles from 0 to 50 GPa, while the Young’s and shear moduli increase by 27–37%, with zero-pressure values ($B_{\mathrm{H}}=144.76$ GPa, $E_{\mathrm{H}}=214.65$ GPa, $G_{\mathrm{H}}=85.66$ GPa) in good agreement with pulse–echo and nanoindentation measurements. Phonon frequencies exhibit a systematic blueshift, with the highest-frequency optical modes hardening at an average rate of 0.102 THz/GPa, and remain real across the entire Brillouin zone, confirming the dynamical stability of the $R\overline{3}m$ phase. The correlated hardening of elastic moduli and phonon frequencies is consistent with pressure-induced bond shortening and the associated strengthening of the interatomic interactions, as evidenced by the monotonic contraction of the Co–O and Li–O bonds (by 4.1% and 9.7%, respectively, over the full pressure range). These results provide a quantitative benchmark for the mechanical behavior of layered oxide cathodes under pressure and offer a reference for related materials.