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Centella asiatica (CA) is a medicinal plant widely used in the East, with many of its phytoconstituents remaining unexplored. In this study, compounds were extracted and identified from C. asiatica to determine its medicinal properties. Phytochemical screening was conducted on shoot, callus, and cell suspension extracts, revealing the presence of tannins, flavonoids, terpenoids, saponins, and steroids in all three cultures, with no alkaloids detected. IC50 values were determined to evaluate the antioxidant activity of the extracts, with the highest value observed for cell suspension culture (20 µg/mL), followed by shoot culture (19 µg/mL), and then callus extract (10 µg/mL), with ascorbic acid as the standard at an IC50 value of 26.25 µg/mL. Finally, density functional theory was used to analyze the structure–activity relationships of the identified compounds from C. asiatica extract. The results suggest that ultrasonic-assisted extraction yielded the highest recovery and antioxidant activity, with a scavenging activity of 79%. This study provides valuable insights into the phytochemical composition and antioxidant potential of C. asiatica, which may have implications for its use in traditional medicine and future drug development.

Anodized aluminum oxide (AAO) molds were used for the production of large-area and inexpensive superhydrophobic polymer films. A controlled anodization methodology was developed for the fabrication of hierarchical micro–nanoporous (HMN) AAO imprint molds (HMN-AAO), where phosphoric acid was used as both an electrolyte and a widening agent. Heat generated upon repetitive high-voltage (195 V) anodization steps is effectively dissipated by establishing a cooling channel. On the HMN-AAO, within the hemispherical micropores, arrays of hexagonal nanopores are formed. The diameter and depth of the micro- and nanopores are 18/8 and 0.3/1.25 µm, respectively. The gradual removal of micropatterns during etching in both the vertical and horizontal directions is crucial for fabricating HMN-AAO with a high aspect ratio. HMN-AAO rendered polycarbonate (PC) and polymethyl methacrylate (PMMA) films with respective water contact angles (WCAs) of 153° and 151°, respectively. The increase in the WCA is 80% for PC (85°) and 89% for PMMA (80°). On the PC and PMMA films, mechanically robust arrays of nanopillars are observed within the hemispherical micropillars. The micro–nanopillars on these polymer films are mechanically robust and durable. Regular nanoporous AAO molds resulted in only a hydrophobic polymer film (WCA = 113–118°). Collectively, the phosphoric acid-based controlled anodization strategy can be effectively utilized for the manufacturing of HMN-AAO molds and roll-to-roll production of durable superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

In modern times, nanoparticles have materialized as indispensable things in contemporary medicine, with a variety of uses in clinical, drug and gene conveyance. In the present study, TiO2 nanoparticles (NPs) prepared from the leaf extracts of Mollugooppositifolia and Trianthema portulacastrum were compared with the chemical TiO2‐NPs for antibacterial and antioxidant activities and environment‐friendly nature through various tools like the UV‐visible, X‐ray diffraction with the aid of other analytical techniques like HR‐TEM, Fourier transform infrared (FT‐IR) and photoluminescence spectroscopic techniques. The morphology of green TiO2‐NPs is found to be spherical, which is supported by HR‐TEM images. FT‐IR analyses and X‐ray diffraction data ensure that the polycrystalline characters of TiO2‐NPs alike to the presence of metal oxide. TiO2‐NPs showed a possible photocatalytic activity for the ruin of acid black 1 dye after disclosure to sunlight. The chemical and green methods of TiO2‐NPs have acid black 1 dye decomposition rates of 86.66% and 94.33%, respectively. The synthesized TiO2‐NPs are also assessed for antimicrobial and antioxidant activities. Green TiO2‐NPs exhibit antibacterial activity against Pseudomonas aeruginosa (17 + 0.56 mm) and Staphylococcus aureus (16 + 0.24 mm) at concentrations as low as 100 μL. The green TiO2‐NPs showed high inhibition of DPPH I radical (50 μg/m) at 95.17 ± 21. Therefore, TiO2‐NPs represent eco‐friendly properties that aid in the degradation of dyes due to their antioxidant activity. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have emerged as a promising alternative to lithium-ion batteries (LIBs) in sectors requiring extensive energy storage. The abundant availability of sodium at a low cost addresses concerns associated with lithium, such as environmental contamination and limited availability. However, SIBs exhibit lower energy density and cyclic stability compared to LIBs. One of the key challenges in improving the performance of SIBs lies in the electrochemical properties of the cathode materials. Among the various cathodes utilized in SIBs, sodium vanadium phosphates (NVPs) and sodium vanadium fluorophosphates (NVPFs) are particularly advantageous. These vanadium-based cathodes offer high theoretical capacity and are cost-effective. Commercialization of SIBs with NVPF cathodes has already begun. However, the poor conductivity of these cathode materials leads to a short cycle life and inferior rate performance. Various synthesis methods have been explored to enhance the conductivity, including heteroatom doping (N, S, and Co), surface modification, the fabrication of porous nanostructures, and composite formation with conductive carbon materials. In particular, cathodes with interconnected hierarchical micro- and nano-porous morphologies have shown promise. This review focuses on the diverse synthesis methods reported for preparing hierarchically porous cathodes. With increased attention, particular emphasis has been placed on carbon composites of NVPs and NVPFs. Additionally, the synthesis of vanadium pentoxide-based cathodes is also discussed. [ABSTRACT FROM AUTHOR]

ZnCo2O4 has emerged as a promising electrode material for supercapacitor applications due to its unique properties and potential for high-performance energy storage. As a transition metal oxide, ZnCo2O4 offers eco-friendly characteristics and favorable diffusion properties, making it an attractive candidate for sustainable energy storage systems. However, the poor conductivity and low surface area of ZnCo2O4 have posed challenges for its optimal utilization in supercapacitors. Various innovative approaches have been explored to overcome these limitations, including the development of ZnCo2O4 with different morphologies such as core-shell and porous structures. This review work aims to provide a comprehensive analysis of diverse synthesis methods employed in recent studies, including hydrothermal growth, solvothermal synthesis, wet chemical methods, and miscellaneous synthesis techniques, each offering unique advantages and influencing the properties of the synthesized materials. The synthesis conditions, such as precursor concentrations, temperature, annealing time, and the incorporation of dopants or additional materials, were found to play a crucial role in determining the electrochemical performance of ZnCo2O4-based supercapacitor electrodes. Core-shell heterostructures based on ZnCo2O4 exhibited versatility and tunability, with the choice of shell material significantly impacting the electrochemical performance. The incorporation of different materials in composite electrodes, as well as doping strategies, proved effective in enhancing specific capacitance, stability, surface area, and charge transfer characteristics. Controlled synthesis of ZnCo2O4 with diverse morphologies and porosity was crucial in improving mechanical strength, surface area, and ion diffusion capabilities. The findings provide valuable insights for the design and engineering of high-performance supercapacitor electrodes based on ZnCo2O4, and suggest exciting avenues for further exploration, including advanced characterization techniques, novel doping strategies, scale-up of synthesis methods, and integration into practical supercapacitor devices. Continued research and development in this field will contribute to the advancement of energy storage technologies and the realization of efficient and sustainable energy storage systems. [ABSTRACT FROM AUTHOR]

In modern times, nanoparticles have materialized as indispensable things in contemporary medicine, with a variety of uses in clinical, drug and gene conveyance. In the present study, TiO 2 nanoparticles (NPs) prepared from the leaf extracts of Mollugooppositifolia and Trianthema portulacastrum were compared with the chemical TiO 2 -NPs for antibacterial and antioxidant activities and environment-friendly nature through various tools like the UV-visible, X-ray diffraction with the aid of other analytical techniques like HR-TEM, Fourier transform infrared (FT-IR) and photoluminescence spectroscopic techniques. The morphology of green TiO 2 -NPs is found to be spherical, which is supported by HR-TEM images. FT-IR analyses and X-ray diffraction data ensure that the polycrystalline characters of TiO 2 -NPs alike to the presence of metal oxide. TiO 2 -NPs showed a possible photocatalytic activity for the ruin of acid black 1 dye after disclosure to sunlight. The chemical and green methods of TiO 2 -NPs have acid black 1 dye decomposition rates of 86.66% and 94.33%, respectively. The synthesized TiO 2 -NPs are also assessed for antimicrobial and antioxidant activities. Green TiO 2 -NPs exhibit antibacterial activity against Pseudomonas aeruginosa (17 + 0.56 mm) and Staphylococcus aureus (16 + 0.24 mm) at concentrations as low as 100 μL. The green TiO 2 -NPs showed high inhibition of DPPH I radical (50 μg/m) at 95.17 ± 21. Therefore, TiO 2 -NPs represent eco-friendly properties that aid in the degradation of dyes due to their antioxidant activity., (© 2024 John Wiley & Sons, Ltd.)