Surface composite design was used to study the effect of the ZnO synthesis conditions on its adsorption of methyl orange (MO) and methylene blue (MB). The ZnO was prepared via hydrothermal treatment under different conditions including temperature (T), precursor concentration (C), pH, and reaction time (t). Models were built using four Design expert-11 software-based responses: the point of zero charge (pHzc), MO and MB removal efficiencies (R_MO, R_MB), MO and MB adsorption capacities (q_MO, q_MB), and hydrodynamic diameter of ZnO particles (D_h). ZnO was characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, UV/VIS spectroscopy, thermal gravimetric analysis (TGA), and dynamic light scattering (DLS). The formation of ZnO was confirmed by the XRD, UV, and FTIR spectra. Results showed a very high efficiency for most of the samples for adsorption of MB, and more than 90% removal efficiency was achieved by 8 samples among 33 samples. For MO, more than 90% removal efficiency was achieved by 2 samples among 33 samples. Overall, 26 of 31 samples showed higher MB adsorption capacity than that of MO. R_MB was found to depend only on the synthesis temperature while R_MO depends on temperature, pH, and reaction time. pHzc was found to be affected by the synthesis pH only while D_h depends on the synthesis pH and precursor concentration.

Zigzag molecular nanobelts have recently captured the interest of scientists because of their appealing aesthetic structures, intriguing chemical reactivities, and tantalizing features. In the current study, first-row transition metals supported on an H₆-N₃-belt[6]arene nanobelt are investigated for the electrocatalytic properties of these complexes for the hydrogen dissociation reaction (HDR). The interaction of the doped transition metal atom with the nanobelt is evaluated through interaction energy analysis, which reveals the significant thermodynamic stability of TM-doped nanobelt complexes. Electronic properties such as frontier molecular orbitals and natural bond orbitals analyses are also computed, to estimate the electronic perturbation upon doping. The highest reduction in the HOMO–LUMO energy gap compared to the bare nanobelt is seen in the case of the Zn@NB catalyst (4.76 eV). Furthermore, for the HDR reaction, the Sc@NB catalyst displays the best catalytic activity among the studied catalysts, with a hydrogen dissociation barrier of 0.13 eV, whereas the second-best catalytic activity is observed for the Zn@NB catalyst (0.36 eV). It is further found that multiple active sites, i.e., the presence of the metal atom and nitrogen atom moiety, help to facilitate the dissociation of the hydrogen molecule. These key findings of this study enhance the understanding of the relative stability, electronic features, and catalytic bindings of various TM@NB catalysts.

The nanohybrid development of metal oxide/conducting polymer as an energy storage material is an active research area, because of the device stability, conductive behavior, and easy fabrication. Herein, needle-like MnO₂ was coupled with polyaniline fabricated through chemical polymerization followed by the hydrothermal process. The characterization results show that MnO₂/polyaniline exhibited a needle-like morphology. Different characterization techniques such as X-ray diffraction patterns and scanning electron microscopy confirmed the formation of the MnO₂/polyaniline nanohybrids. The electrochemical performance, including cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), specific capacitance (C_sp), and cyclic stability, was examined using a three-electrode assembly cell. The optimized electrode displayed a C_sp of 522.20 F g⁻¹ at a current load of 1.0 A g⁻¹ compared with the other electrodes. The developed synergism during MnO₂/polyaniline fabrication provided enhanced conductive channels and stability during the charge–discharge process.

A mesoporous anatase/silica core–shell nanostructure (ASCS) was synthesized via a sol–gel method at 90 °C, and then cadmium sulfide quantum dots (CdS-QDs) were encapsulated in it, forming CdS-ASCS. The CdS-ASCS was synthesized to enhance the efficiency of heterogeneous nanophotocatalysts. The CdS-ASCS nanoparticles exhibited a core–shell morphology with a particle size of approximately 1.8 nm and a shell thickness of about 8 nm. The uniform distribution of cadmium, sulfur, titanium, and silicon was observed, along with a pore radius of roughly 2.5 nm and a bandgap energy of approximately 3.2 eV. Under ultraviolet irradiation, the CdS-ASCS demonstrated a photocatalytic degradation of 91% for methylene blue (MB) within 240 min, with a rate constant of 0.01 min⁻¹. These findings suggested that CdS-ASCS is a highly effective photocatalyst with promising applications in water purification.

Transition-metal-dichalcogenide materials (TMDs) are proceeding toward future nanoelectronic devices as comprehensive research in this domain proves their extraordinary properties and potential for application in diverse fields. There are associated challenges related to the quality of grown material, grain size, and adaptiveness to a selected substrate, and chemical vapor deposition is considered the ideal technique in these regards. Salt-assisted growth of two-dimensional TMDs has recently solved some growth issues associated with the high melting points of some oxides and the low vapor pressure, which leads to limitations in the growth area. In the current study, NaCl-assisted growth is used to produce high-quality monolayered films on Si/SiO₂ and multilayered films of MoS₂ on fluorine-doped tin oxide. An empirical methodology was used to determine optimal conditions for sample growth. Factors such as precursor weights and ratios, temperature, and sulfurization were investigated with respect to preparing samples for exploitable applications.