Current Issue : January-March Volume : 2026 Issue Number : 1 Articles : 6 Articles
The present study investigates dye-sensitized solar cells (DSSCs) incorporating natural extracts from the microalgae Spirulina and Chlorella as photosensitizers. TiO2-based electrodes were prepared and immersed in methanolic algae extracts for 24 and 48 h. UV–Vis spectroscopy revealed absorption peaks near 400 nm and 650 nm, characteristic of chlorophyll. Electrochemical analyses, including photochronoamperometry and open-circuit potential, confirmed the photosensitivity and charge transfer capabilities of all systems. The cell sensitized with Chlorella after 48 h of immersion exhibited the highest energy conversion efficiency (0.0184% ± 0.0015), while Spirulina achieved 0.0105% ± 0.0349 after 24 h. Chlorella’s superior performance is attributed to its higher chlorophyll content and enhanced light absorption, facilitating more efficient electron injection and interaction with the TiO2 surface. Although the efficiency remains lower than that of conventional siliconbased solar cells, the results highlight the potential of natural colorants as sustainable and low-cost alternatives for photovoltaic applications. Nonetheless, further, improvements are required, particularly in dye stability and anchorage, to improve device performance. This research reinforces the viability of natural photosensitizers in DSSC technology and supports continued efforts to optimize their application....
The discharge of dye wastewater poses a serious threat to the environment and human health. Membrane separation technology based on electrostatic adsorption is considered an effective method for dye removal. However, its longterm application is hindered by the saturation of adsorption sites. In this study, an anionic dye-adsorbing membrane was fabricated via a co-deposition strategy, combined with patterned silver gel to impart conductivity. Acting as a cathode, the membrane electrolyzes water to generate OH− ions at the interface that deprotonate the functional groups, thereby releasing the adsorbed dyes in situ. The membrane exhibits excellent dye rejection performance and enables sustainable separation over multiple cycles under this electro-assisted cleaning. This strategy avoids the use of additional reagents or secondary chemical pollutants, offering an efficient and sustainable membrane separation solution for the treatment of dye-containing wastewater....
Currently, the trade-off between oxygen permeation flux and structural stability in conventional perovskite oxides restricts the practical application of oxygen permeable membranes. In this study, a high-entropy design was applied to the B-site of BSCF matrix materials, resulting in the successful synthesis of a high-entropy perovskite, Ba0.5Sr0.5Co0.71Fe0.2Ta0.03Ni0.03Zr0.03O3−δ. The crystal structure, microstructure, and elemental composition of the material were systematically characterized and analyzed. Theoretical analysis and experimental characterization confirm that the material exhibits a stable single-phase high-entropy perovskite oxide structure. Under He as the sweep gas, the membrane achieved an oxygen permeation flux of 1.28 mL·cm−2·min−1 and operated stably for over 100 h (1 mm thick, 900 ◦C). In a 20% CO2/He atmosphere, the flux remained above 0.92 mL·cm−2·min−1 for over 100 h, demonstrating good CO2 tolerance. Notably, when the sweep gas is returned to the pure He atmosphere, the oxygen permeation flux fully recovers to 1.28 mL·cm−2·min−1, with no evidence of leakage. These findings indicate that the proposed B-site doping strategy can break the trade-off between oxygen permeability and structural stability in conventional perovskite membranes. This advancement supports the industrialization of oxygen permeable membranes and offers valuable theoretical guidance for the design of high-performance perovskite materials....
The prompt and reliable detection of NH3 leakage at room temperature (RT) is considered important for safety assurance and sustainable production. Although chemiresistive NH3 sensors feature low cost and structural simplicity, their practical application is hindered by high operating temperatures and inadequate selectivity. Metal–organic frameworks (MOFs) and their derivatives offer a promising approach to address these limitations. In this work, Ce-BDC precursors with tunable particle sizes and crystallinity were synthesized by adjusting the raw material concentration. Controlled pyrolysis yielded a series of CeO2-C-X (X = 0.5, 1, 1.5, 2) materials with nanosized particles. Among them, the CeO2-C-1 sensor delivered a high response of 82% toward NH3 under 40% relative humidity at RT. Moreover, it possessed excellent selectivity, repeatability, and rapid response-recovery behavior compared with the other samples. CeO2-C-1 also remained stable under varying oxygen and humidity conditions, demonstrating high applicability. The superior sensing properties may be attributed to its high specific surface area and optimized mesoporous structure, which facilitated efficient gas adsorption and reaction. These findings demonstrated that precise control of MOF precursors and the structure in CeO2 nanomaterials was critical for achieving high-performance gas sensing and established Ce-MOF-derived CeO2 as a promising sensing material for NH3 detection at RT....
The rate of decrease of molecular hydrogen formation with an increase in the concentration of CO2 is observed during the radiolysis of mixtures of H2O with CO2. The rates of formation of all products (H2, CO, CH4, and relatively heavy hydrocarbons) increase with increasing absorbed dose and amount of organic matter in mixtures with stable concentrations of CO2, H2O, and 40KCl.There is a decrease in the rate of formation of H2 and CH4, and an increase in the rate of elementary reactions of the transformation of light radiolysis products (H2, CO, CH4) into relatively heavy products (C6, C7, C8) with an increase in CO2 concentration. The results obtained show the expediency of taking into account the contribution of ionizing radiation from radionuclides present in the environmental components, when considering multistage biochemical mechanisms of photosynthesis, in order to explain the initiation of energy-intensive processes of CO2 and H2O decomposition. The analysis showed the presence of natural radionuclides in all samples of water, soil, vegetation and livestock products. The development of green vegetation in fertile soils is directly proportional to the concentration of microelements and natural radionuclides, in the range of concentrations of microelements formed in the soil cover of the planet. The high development of vegetation, green cover and trees in fertile areas is explained by the stimulation of photosynthesis process by relatively high concentrations of microelements and natural radionuclides....
This study employs Raman spectroscopy for the first time to characterize (Z)- N-(2-amino-1,2-dicyanovinyl) formimidate. Raman, in addition to IR and NMR (acquired and literature), helps confirm the molecular structure of the compound. Additionally, the melting point (mp 132˚C - 134˚C) data helps confirm the compound’s purity. Raman spectra, measured with a 785 nm laser, reveal key vibrational modes, including two peaks at 2242 and 2206 cm−1 (CN stretches), two peaks at 1634 and 1591 cm−1 (C=N and C=C stretches), two peaks at 1369 and 1224 cm−1 attributed to (C-O and N-H bands). The acquired FT-IR spectra showed characteristic peaks at 3416, 3304, 2243, 2208, 1635, 1606 cm−1 as reported by IR data of Alves et al (1990) [1] and US Patent #US 8,518,901 B2 (2013) [2] at 3309 cm−1 (NH/NH2 stretches), 2247 cm−1 (CN stretches), 2207 cm−1 (CN stretches)~1636 cm−1 (C=N stretches), 1608, 1256 (C-0 str.), 810 cm−1 supporting the presence of cyano, formimidate, and amino groups. These findings validated the compound’s identity and highlighted the complementary nature of Raman and IR techniques for formimidate analysis....
Loading....