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This paper presents an overview of solar dryer technologies, highlighting current concerns, offering potential research directions, and gathering the most recent advancements. A sustainable and environmentally beneficial way to preserve food products, agricultural produce, and other commodities is solar drying. The review starts off by explaining the basic ideas behind solar drying procedures, including different design setups and operating parameters. The performance of various solar dryer types- direct, indirect, and hybrid systems- is methodically assessed in this paper, with a focus on each system’s benefits and drawbacks. Indirect natural convection solar drying technique was used to dry banana slices with drying efficiency of 22.38%. Also, v shape corrugations were used on absorber plate to further improve the drying efficiency. It also covers new developments in design elements and materials that improve the dependability and efficiency of solar dryers. Absorber plates were coated with black paint containing 1% graphene nanomaterial. Impact of thickness of glass cover on drying efficiency was studied. Parabolic concentrators are used to enhance the efficiency of solar dryers. The drying time was reduced by 21% compared with solar dryers without concentrator. Additionally, the review covers important factors like affordability, scalability, and adaptability to various applications and climates. Major Findings: The performance of various solar dryers has been studied in this paper. It has been found that drying efficiency can be improved by providing black paint coating containing 1% graphene nanomaterial. Parabolic concentrators have a significant impact on the performance of solar dryers. [ABSTRACT FROM AUTHOR]

This study explores amine-functionalized dendritic fibrous nanosilica (DFNS) as a highly effective, base-free heterogeneous catalyst for nitro-aldol (Henry) condensation and additive-free CO2 utilization. Initially, high surface area DFNS was synthesized using a novel template in an emulsion biphasic system and chemically processed to create DFNS@NH2 for the Henry reaction and further quaternized to form DFNS@TBAB for CO2 utilization. DFNS is expected to outperform conventional mesoporous materials (SBA-15 and MCM-41) due to its dendritic morphology, higher surface area, superior mass transfer, ease of functionalization, and greater active site exposure, enhancing its catalytic efficiency and versatility. In addition, the total basicity values for DFNS@NH2 and DFNS@TBAB were determined to be 0.48 and 0.124 mmol g−1, respectively. Furthermore, FeSEM, TEM, and HR-TEM analyses evidenced the dendritic morphology of the solid substrate with a fibrous structure termed DFNS. Amine-functionalized DFNS achieved complete conversion of benzaldehyde to β-nitrostyrene with over 99% selectivity at 50 °C in 12 h using nitromethane. It successfully catalyzed a range of substrates in the Henry reaction, including electron-donating and electron-withdrawing aromatic aldehydes and biologically derived aldehydes such as furfural and 5-methyl furfural. Electron-withdrawing groups on aromatic rings showed reduced catalytic activity. Furthermore, DFNS functionalized with n-butyl bromide produced a quaternary amine catalyst capable of converting CO2 and styrene oxide to styrene carbonate without external additives, achieving 94% conversion and 98% selectivity. This dual functionality highlights DFNS's potential in carbon–carbon bond formation and CO2 utilization, offering a promising route for CO2 emission mitigation through chemical conversion. [ABSTRACT FROM AUTHOR]

Electrode materials engineering at the nanoscale is essential to improve the electrochemical performance for next‐generation energy storage devices. Herein, a novel approach of sodium substitution in the tungsten oxide matrix is highligting the enhancement of the pseudocapacitor performance of the electrode in an aqueous asymmetric supercapacitor. The sodium‐substituted tungsten trioxide (NWO) and pristine tungsten oxide (PWO) nanoflowers prepared by a single‐step hydrothermal process has presented. The tetragonal crystal structure and nanoflower morphology has maintained even after Na substitution. The electrochemical properties of PWO and NWO have investigated with three‐electrode setups in 1 M H2SO4 aqueous electrolyte. The specific capacitance of PWO and NWO exhibits 104 F g−1 and 476 F g−1 at 1 A g−1, respectively. Furthermore, an aqueous asymmetric supercapacitor (AAS) of NWO demonstrates a specific capacitance of 41 F g−1, an energy density of 13 W h kg−1, and a power density of 3750 W kg−1. An excellent stability of AAS has achieved with 100 % capacitance retention from 1000 to 5000 cycles. The sodium substitution significantly enhanced the pseudocapacitive behavior, attributed to enhanced electroactive sites, conductivity, surface area, and chemical stability. It shows the potential of NWO nanoflowers as a promising candidate for next‐generation supercapacitor devices. [ABSTRACT FROM AUTHOR]