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The development of energy-efficient and sustainable building materials is imperative to reduce energy consumption in the construction sector. This study addresses both the applied problem of increased solar heat gain and decreased indoor thermal comfort, as well as the scientific problem of reducing the thermal conductivity of clay bricks. It investigates the incorporation of recycled spent mushroom materials, consisting of Pleurotus florida mycelia and rice husk waste, as a novel additive in the production of fired clay bricks (FCBs) to enhance thermal insulation properties. The developed bricks were utilized in an optimized wall design for a residential building in New Cairo, Egypt. The wall design is created using energy modeling software, including Honeybee, Ladybug, Climate Studio, and Galapagos. The results demonstrate that an optimal waste content of 15% and a firing temperature of 900 °C yield the best thermal performance. Compared to traditional FCB walls, the new design incorporating the florida waste additive significantly improves thermal comfort, as indicated by a lower predicted mean vote and predicted percentage of dissatisfaction. Furthermore, the developed walls contribute to a reduction in CO2 emissions of 6% and a decrease in total energy consumption of 38.8%. The incorporation of recycled florida waste offers a sustainable approach to enhancing standard brick fabrication processes. This work highlights the promise of agricultural waste valuation for the development of eco-friendly and energy-efficient building materials. Future research should explore the mechanical strength, acoustics, cost–benefit analysis, and field implementation of the developed walls, thereby addressing both the scientific and applied aspects of the problem. [ABSTRACT FROM AUTHOR]

This study presents an efficient way to degrade methylene blue (MB) present in water via photodegradation using H2O2 as an oxidant in the presence of UV irradiation and without the use of a catalyst. The reaction variables, employed to evaluate the performance of the photodegradation process using the UV/H2O2 system, were the amount of H2O2 in the reacting solution and the initial concentration of methylene blue. The degradation of methylene blue in the presence of H2O2 was not observed during agitation in darkness. The degradation time decreased as the H2O2 concentration increased after the ideal concentration was reached. At this stage, as it began to scavenge the generated hydroxyl radicals, the rate of degradation became inversely proportional to the concentration of H2O2. An increase in the quantities of MB and H2O2 improved the degradation efficiency because the oxidation process was aided by using the appropriate amount of H2O2 and an ideal length of UV light exposure. The experimental data obtained were well-fitted to zero-order reaction kinetics based on the high values of the correlation coefficient. It is believed that the OH radicals (OH●) generated during the breakdown of H2O2 and the generated O2●− species attack the MB molecules and produce MB radicals (MB●). These MB radicals further experience oxidation and convert to intermediates and finally to CO2 and H2O. The UV/H2O2 system proved to be quite efficient for the photodegradation of methylene blue without the use of any solid catalyst. This UV/H2O2 system can be employed in the degradation of other organic pollutants in industrial wastewater. [ABSTRACT FROM AUTHOR]

In this study, 2D Co-B nanosheet-decorated 1D TiO2 nanofibers (2D Co-B NS-decorated 1D TiO2 NFs) are synthesized via electrospinning and an in situ chemical reduction technique. The as-prepared catalyst showed excellent catalytic performance in H2 generation from sodium borohydride (SBH). When compared to naked Co-B nanoparticles, the catalytic activity of the 2D Co-B NS-decorated 1D TiO2 NFs catalyst for the hydrolysis of SBH is significantly enhanced, as demonstrated by the high hydrogen generation rate (HGR) of 6020 mL min−1 g−1 at 25 °C. The activation energy of hydrolysis was measured to be 30.87 kJ mol−1, which agreed with the reported values. The catalyst also showed good stability. Moreover, the effects of SBH, catalyst concentration, and temperature on the catalytic performance of 2D Co-B NS-decorated 1D TiO2 NFs were studied to gain a comprehensive understanding of the dehydrogenation mechanism of SBH. Based on these findings, we conclude that 2D Co-B NS-decorated 1D TiO2 NFs are effective catalytic materials for the dehydrogenation of SBH. [ABSTRACT FROM AUTHOR]

The present study involves the synthesis of photocatalytic composite nanofibers (NFs) comprising ilmenite nickel titanite-supported carbon nanofibers (NiTiO3/TiO2@CNFs) using an electrospinning process. The photocatalytic composite NFs obtained were utilized in hydrogen (H2) production from the photohydrolysis of ammonia borane (AB). The experimental findings show that the photocatalytic composite NFs with a loading of 25 mg had a good catalytic performance for H2 generation, producing the stoichiometric H2 in 11 min using 1 mmol AB under visible light at 25 °C and 1000 rpm. The increase in catalyst load to 50, 75, and 100 mg leads to a corresponding reduction in the reaction time to 7, 5, and 4 min. The findings from the kinetics investigations suggest that the rate of the photohydrolysis reaction is directly proportional to the amount of catalyst in the reaction system, adhering to a first-order reaction rate. Furthermore, it was observed that the reaction rate remains unaffected by the concentration of AB, thereby suggesting a reaction of zero order. Increasing the reaction temperature results in a decrease in the duration of the photohydrolysis reaction. Furthermore, an estimated activation energy value of 35.19 kJ mol−1 was obtained. The composite nanofibers demonstrated remarkable and consistent effectiveness throughout five consecutive cycles. The results suggest that composite NFs possess the capacity to function as a feasible substitute for costly catalysts in the process of H2 generation from AB. [ABSTRACT FROM AUTHOR]

This study explores the potential for making lightweight bricks via the use of dry, pulverized spent mushroom materials (SMM) as a thermal insulator. There are five distinct replacement proportions of SMM that are used, and they range from 0% to 15% of the weight of the clay. The firing of the fabricated bricks at temperatures of 700, 800, and 900 °C led to the development of pores on the interior surface of the bricks as a consequence of the decomposition of SMM. The impact of SMM on the physicomechanical characteristics of fabricated bricks is assessed based on standard codes. Compressive strength, bulk density, and thermal conductivity decreased as the SMM content increased, reaching up to 8.7 MPa, 1420 kg/m3, and 0.29 W/mK at 900 °C and 15% substitution percentage. However, cold water absorption, boiling water absorption, linear drying shrinkage, linear firing shrinkage, and apparent porosity increased with the increase in SMM, reaching 23.6%, 25.3%, and 36.6% at 900 °C and 15% substitution percentage. In the study simulation model, there was a significant improvement in energy consumption, which reached an overall reduction of 29.23% and 21.49% in Cario and Jazan cities, respectively. [ABSTRACT FROM AUTHOR]

Sodium borohydride (SBH) hydrolysis in the presence of cheap and efficient catalysts has been proposed as a safe and efficient method for generating clean hydrogen energy for use in portable applications. In this work, we synthesized bimetallic NiPd nanoparticles (NPs) supported on poly(vinylidene fluoride-co-hexafluoropropylene) nanofibers (PVDF-HFP NFs) via the electrospinning approach and reported an in-situ reduction procedure of the NPs being prepared by alloying Ni and Pd with varying Pd percentages. The physicochemical characterization provided evidence for the development of a NiPd@PVDF-HFP NFs membrane. The bimetallic hybrid NF membranes exhibited higher H2 production as compared to Ni@PVDF-HFP and Pd@PVDF-HFP counterparts. This may be due to the synergistic effect of binary components. The bimetallic Ni1−xPdx(x = 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3)@PVDF-HFP nanofiber membranes exhibit composition-dependent catalysis, in which Ni75Pd25@PVDF-HFP NF membranes demonstrate the best catalytic activity. The full H2 generation volumes (118 mL) were obtained at a temperature of 298 K and times 16, 22, 34 and 42 min for 250, 200, 150, and 100 mg dosages of Ni75Pd25@PVDF-HFP, respectively, in the presence of 1 mmol SBH. Hydrolysis utilizing Ni75Pd25@PVDF-HFP was shown to be first order with respect to Ni75Pd25@PVDF-HFP amount and zero order with respect to the [NaBH4] in a kinetics study. The reaction time of H2 production was reduced as the reaction temperature increased, with 118 mL of H2 being produced in 14, 20, 32 and 42 min at 328, 318, 308 and 298 K, respectively. The values of the three thermodynamic parameters, activation energy, enthalpy, and entropy, were determined toward being 31.43 kJ mol−1, 28.82 kJ mol−1, and 0.057 kJ mol−1 K−1, respectively. It is simple to separate and reuse the synthesized membrane, which facilitates their implementation in H2 energy systems. [ABSTRACT FROM AUTHOR]

The successful support of bimetallic NiCo alloy nanoparticles (NPs) on poly(vinylidene fluoride-co-hexafluoropropylene) nanofibers (PVDF-HFP NFs) was achieved through electrospinning (ES) and in situ reduction. The synthesis and physicochemical characterization of Ni-Co@PVDF-HFP NFs with a range of bimetallic compositions (Ni1−xCox, x = 0, 0.1, 0.3, 0.5, 0.7, 0.9, and 1) supported on PVDF-HFP NFs was undertaken. In comparison to their counterparts (Ni-PVDF-HFB and Co-PVDF-HFB), the bimetallic hybrid NF membranes demonstrated a significantly increased volume of H2 generation from sodium borohydride (SBH). The high performance of bimetallic catalysts can be attributed mostly to the synergistic impact of Ni and Co. Among all fabricated catalysts, Ni0.3Co0.7@PVDF-HFP produced the highest H2 production in a short time. The maximum generated H2volume was 118 mL in 11.5, 9, 6, and 4.5 min at 298, 308, 318, and 328 K, respectively. Kinetic analyses showed that the hydrolysis process proceeded as a quasi-first-order reaction with respect to the amount of catalyst and as a zero-order reaction with respect to the concentration of SBH. Thermodynamics studies were also undertaken and the parameters were calculated as Ea, ΔS, and ΔH = 30.17 kJ/mol, 0.065 kJ/mol, and 27.57 kJ/mol K, respectively. The introduced NFs can be easily separated and reused, which facilitates their industrialization and commercialization applications in hydrogen storage systems. [ABSTRACT FROM AUTHOR]

A nanocomposite comprised of nickel titanate/titania nanoparticles decorated with carbon nanofibers (NiTiO3/TiO2-decorated CNFs) is successfully synthesized via electrospinning and further utilized for methylene blue (MB) photodegradation. The morphology, phase, structural and chemical composition of the nanocomposite is investigated via scanning electron microscope, X-ray diffraction and transmission electron microscope equipped with energy dispersive X-ray. A mathematical model is developed to predict the photocatalytic activity of the produced nanocomposite by considering parameters such as initial dye concentration, light intensity, reaction temperature, and catalyst dosage. The reaction rate constant K1 decreased from 0.0153 to 0.0044 min−1 with an increase in the MB concentration from 5 to 15 mg L−1, while K2, K3, and K4 were found to increase with the increase in reaction temperature (0.0153 to 0.0222 min−1), light intensity (0.0153 to 0.0228 min−1) and catalyst dose concentration (0.0153 to 0.0324 min−1), respectively. The results obtained are found to be in good agreement with the modeling results and showed effective photodegradation activity. The performance of our catalyst is found to be better compared to other catalysts previously reported in the literature. The recyclability data of the synthesized NiTiO3/TiO2-decorated CNFs catalyst for four runs show that the catalyst is quite stable and recyclable. This nanocomposite photocatalyst offers a low-cost solution for wastewater pollution problems and opens new avenues to further explore the electrospinning method for the synthesis of nanocomposites. [ABSTRACT FROM AUTHOR]

In this study, titania/silica nanocomposite and mesoporous TiO2 (m-TiO2) photocatalysts are developed by KIT-6 template via a sol-gel approach. The synthesized photocatalysts are characterized by XRD, EDX, SEM, Raman, PL, and UV–vis DRS analysis techniques. The as-synthesized series revealed a high surface area, smaller size, a greater number of accessible active sites, and enhanced light-harvesting capability. The m-TiO2 photocatalysts' charge recombination capability was curiously inferior to the rest of as-synthesized TiO2/KIT-6 nanocomposite materials. The band-gap of as-synthesized materials were suitable for their activity in UV light irradiations. It was pragmatic that the photocatalytic degradation efficiency of m-TiO2 photocatalysts was superior as compared to that of commercial TiO2 photocatalyst under UV light irradiations, owing to the synergistic outcome of the anatase phase and a greater number of accessible active-sites availability as a result of high surface area. Moreover, the m-TiO2 was critically evaluated by investigating various parameters affecting the photocatalytic degradation reaction of MB including the effect of irradiation time, pH, catalyst dosage, and dye concentration. The m-TiO2, 45wt% composite material and commercial-TiO2 exhibited 99.27, 91.20, and 84.67% degradation of methyl blue in 50 min, respectively. Finally, the m-TiO2 exhibited excellent recyclability with negligible loss of activity performance. [ABSTRACT FROM AUTHOR]