Vanadium disulfide−black phosphorus (VS 2 −BP) hybrids were synthesized by a one-pot hydrothermal-assisted method to achieve enhanced electrochemical activity for supercapacitor applications. The concentration of BP was optimized to prevent the restacking nature of VS 2 and to enrich the active edges for electrolytic ion intercalation. The charge storage kinetics of the best-performing VS 2 −BP as an active electrode has demonstrated the dominance of the pseudocapacitive nature of the material. Furthermore, by sandwiching with a PVA/K 2 SO 4 gel electrolyte, an all-solid-state (ASS) vanadium disulfide−black phosphorus-50 mg (VS 2 −BP-50) symmetric device was developed on highly conductive carbon paper. The ASS VS 2 −BP-50 symmetric device displays the highest specific areal capacitance of 203.25 mF/cm 2 and exhibits the maximum areal energy density of 28.22 μW h cm −2 at an areal power density of 596.09 mW cm −2 , outperforming the previous literature. To understand the origin of the high quantum capacitance, we used density functional theory (DFT) and found that the charge accumulation region between VS 2 and BP monolayers and the charge transfer are the origin of the improved density of states in the VS 2 −BP hybrid. Moreover, exceptional mobility of K + ions and a higher diffusion rate were observed using the DFT method.

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Recently, dielectric materials with high energy storage capacity, low loss, and good temperature stability are highly desired for the rapidly growing field of power electronics. In the current work, we have investigated the change in electrical, optical, and dielectric properties by varying the concentration of compositional elements Sn and Mn. We have prepared the Sn1–x Mn x S (0.1, 0.3, 0.5, 0.7, and 0.9) matrix by using the simple single-step hydrothermal method. The samples show that the reflectance percentage increased with the increase of the Mn amount in the composition. The samples exhibit narrow band gap values, which further increase with the Mn content. The band gap value increases from 0.43 to 0.56 eV. The structural analysis shows that the prepared samples are polycrystalline in nature, having SnS and MnS phases. Furthermore, the crystallite sizes increase with an increase in Mn addition, whereas dislocation density and strain decrease simultaneously. The refractive index is calculated from optical band gap values by using the Dimitrov and Sakka equation. The morphological study reveals the uniformity in size and shape of the prepared composition throughout the sample. The presence of compositional elements Sn, Mn, and S is confirmed by EDX analysis. The electrical study reveals that the sample shows good electrical properties, which increase with the Mn contents. The dielectric behavior as a function of frequency and temperature was investigated, and the parameters like dielectric constant, AC conductivity, impedance spectroscopy, and electric modulus were deeply analyzed. All the above optical, electrical, and dielectric properties of the SnMnS matrix have potential use in the field of electronic and energy storage device applications.

The influence of 532 nm laser irradiation for different times on the optical changes of Ag10In15S15Se60 thin films. The irradiation influenced the structural, linear and the nonlinear optical parameters.

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