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Abstract This research aims to develop chitosan-zein protein films supplemented withBergenia ciliata(Bc) extract, a traditionally important medical herb of Himalayan origin. The film’s physicochemical, mechanical, antioxidant, and antimicrobial properties were systematically explored. The opacity of chitosan film increased from 2.42 ± 0.97 to 10.32 ± 1.44 upon introducing zein (Z) protein in chitosan (Cs) in a 1:2 ratio (w/w); conferring enhanced UV-blocking attributes. IncorporatingB. ciliataextracts in the chitosan-zein film (Cs-Z-Bc) under optimized conditions further increased the opacity to 16.27 ± 1.03 without compromising the tensile strength. The α-diphenyl-β-picrylhydrazyl scavenging activity of the Cs-Z-Bc film was found to be 97.07 ± 1.09%. Additionally, these optimized films displayed significant antimicrobial efficacy, with zones of inhibition of 11.4 mm measured for gram-positive strains likeC. subtilisandS. aureusand 11.2 mm and 11.1 mm forE. coliandK. pneumoniae(gram-negative) bacterial strains. The film also showed excellent biodegradable properties. The shelf life study of Himalayan cheese was significantly increased when wrapped with the film. These findings suggested thatB. ciliataextract-fortified chitosan-zein films can be an excellent food packaging material. 

Hydrothermal and photoreduction/deposition methods were used to fabricate Ag nanoparticles (NPs) decorated CoMoO₄rods. Improvement of charge transfer and transportation of ions by making heterostructure was proved by cyclic voltammetry and electrochemical impedance spectroscopy measurements. Linear sweep voltammetry results revealed a fivefold enhancement of current density by fabricating heterostructure. The lowest Tafel slope (112 mV/dec) for heterostructure compared with CoMoO₄(273 mV/dec) suggested the improvement of electrocatalytic performance. The electrochemical CO₂reduction reaction was performed on an H-type cell. The CoMoO₄electrocatalyst possessed the Faraday efficiencies (FEs) of CO and CH₄up to 56.80% and 19.80%, respectively at  − 1.3 V versus RHE. In addition, Ag NPs decorated CoMoO₄electrocatalyst showed FEs for CO, CH₄, and C₂H₆were 35.30%, 11.40%, and 44.20%, respectively, at the same potential. It is found that CO₂reduction products shifted from CO/CH₄to C₂H₆when the Ag NPs deposited on the CoMoO₄electrocatalyst. In addition, it demonstrated excellent electrocatalytic stability after a prolonged 25 h amperometric test at  − 1.3 V versus RHE. It can be attributed to a synergistic effect between the Ag NPs and CoMoO₄rods. This study highlights the cooperation between Ag NPs on CoMoO₄components and provides new insight into the design of heterostructure as an efficient, stable catalyst towards electrocatalytic reduction of CO₂to CO, CH₄, and C₂H₆products. 

Abstract Cu₂O has been successfully synthesized in different morphologies/sizes (nanoparticles and octahedrons) via a low-temperature chemical reduction method. Trapping metal ions in an ice cube and letting them slowly melt in a reducing agent solution is the simplest way to control the nanostructure. Enhancement of charge transfer and transportation of ions by Cu₂O nanoparticles was shown by cyclic voltammetry and electrochemical impedance spectroscopy measurements. In addition, nanoparticles exhibited higher current densities, the lowest onset potential, and the Tafel slope than others. The Cu₂O electrocatalyst (nanoparticles) demonstrated the Faraday efficiencies (FEs) of CO, CH₄, and C₂H₆up to 11.90, 76.61, and 1.87%, respectively, at −0.30 V versus reference hydrogen electrode, which was relatively higher FEs than other morphologies/sizes. It is mainly attributed to nano-sized, more active sites and oxygen vacancy. In addition, it demonstrated stability over 11 h without any decay of current density. The mechanism related to morphology tuning and electrochemical CO₂reduction reaction was explained. This work provides a possible way to fabricate the different morphologies/sizes of Cu₂O at low-temperature chemical reduction methods for obtaining the CO, CH_4,and C₂H₆products from CO₂ 

Metal indium sulfides (ZnIn₂S₄, NiIn₂S₄, and CuInS₂) were synthesized using a hydrothermal method for electrochemical reduction of CO₂in to methane. 

Abstract We synthesized the silver‐decorated copper microsphere via the hydrothermal method followed by photoreduction of silver ions. Sub 100 nm Ag nanoparticles anchored on the surface of Cu microspheres enhance the electrochemical performance and the selectivity of the CO₂reduction into CH₄. Incorporating Ag nanoparticles onto Cu lowers the charge transfer resistance, enhancing the catalyst's conductivity and active site and increasing the rate of CO₂reduction. The faradaic efficiency of silver nanoparticles decorated copper microsphere for methane was 70.94 %, almost twice that of a copper microsphere (44 %). The electrochemical performance showed higher catalytic properties, stability, and faradaic efficiency of silver‐decorated copper microspheres. 

High-pressure studies on elements play an essential role in superconductivity research, with implications for both fundamental science and applications. Here we report the experimental discovery of surprisingly low pressure driving a novel germanium allotrope into a superconducting state in comparison to that for α-Ge. Raman measurements revealed structural phase transitions and possible electronic topological transitions under pressure up to 58 GPa. Based on pressure-dependent resistivity measurements, superconductivity was induced above 2 GPa and the maximum Tc of 6.8 K was observed under 4.6 GPa. Interestingly, a superconductivity enhancement was discovered during decompression, indicating the possibility of maintaining pressure-induced superconductivity at ambient pressure with better superconducting performance. Density functional theory analysis further suggested that the electronic structure of Ge (oP32) is sensitive to its detailed geometry and revealed that disorder in the β-tin structure leads to a higher Tc in comparison to the perfect β-tin Ge. 

Cerium oxide (CeO₂) photo/electrocatalysts for energy storage and environmental applications have attracted considerable interest because of stable crystal structure, low toxicity/cost, superior chemical stability, stable redox (Ce³⁺/Ce⁴⁺) pairs, abundant oxygen defects, and capablility for intense interaction with other materials. However, the wide bandgap and poor conductivity lower the CeO₂photo/electrocatalytic and energy storage performances. To overcome these limitations, various modification strategies (tuning morphology, doping or loading of metal nanoparticles, and heterostructures) have been applied for the improvement of photocatalytic (removal of organic contaminants from water/wastewater and H₂production and CO₂reduction reactions) efficiency, electrocatalytic (hydrogen/oxygen evolution reactions and CO₂reduction reactions), and energy storage performances (supercapacitor) of CeO₂‐based materials. Herein, the recent progress of CeO₂‐based materials for electro(photo)catalysis and energy storage applications has been discussed. The challenges and possible direction of CeO₂‐based materials for electro(photo)catalysis and energy storage applications have been emphasized. Furthermore, this comprehensive review is expected to advance the design of CeO₂‐based materials and their applications in electro(photo)catalysis and energy.