Aims: To improve solar water disinfection using a photocatalysing semi-conductor and to study the mechanisms involved in this process.
Methods And Results: Cells of Escherichia coli were used as the microbiological indicator to study the possibility of improving the efficiency of solar water disinfection using titanium dioxide (TiO2) as a photooxidizing semi-conductor. TiO2 was used either as a suspended powder or in an immobilized form. Both applications improved the efficiency of solar disinfection. TiO2 in suspension was more effective than the immobilized form, producing enhancement factors of 1.62 and 1.34, respectively. The concentration of TiO2 greatly affected efficiency, with a maximum effect at 1 mg ml(-1). Higher TiO2 concentrations reduced the efficiency. Dimethyl sulphoxide (DMSO) and cysteamine (Cys), hydroxyl radical (OH.) scavengers, were used to elucidate the mechanisms involved in the presence of TiO2. Both DMSO and Cys totally abolished the enhancing effect produced by the presence of TiO2.
Conclusions: Sunlight has a potential water disinfecting capacity. The use of TiO2 greatly improved this efficiency. The effect of TiO2 was mainly concentration-dependent, giving maximum efficiency at 1 mg ml(-1). The presence of DMSO and Cys removed the TiO2-induced enhancement, indicating that OH. may be involved in the process of cell killing.
Significance And Impact Of The Study: The efficiency of solar disinfection is limited and time-consuming and needs to be improved. The use of a semi-conductor is promising as it reduces the time of exposure and therefore increases the efficiency of solar disinfection. This would allow for the availability of good quality water, and hence would improve the quality of life.
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Sci Rep
January 2025
Department of Information Technology, College of Computers and Information Technology, Taif University, P.O. Box 11099, Taif, 21944, Saudi Arabia.
We proposed the ultrawideband solar absorber using the multisized metal resonator oriented on the top of the multilayered Metal-SiO₂-MXene-MgF₂-Tungsten structure. We have carried out a numerical investigation of this structure for the 100-2500 THz frequency, which covers the infrared, visible, and UV spectra. The proposed solar absorber is numerically investigated for the different physical parameters, such as the height of the layers, unit cell size, and resonator orientation, to identify optimized results for the high absorption capacity.
View Article and Find Full Text PDFNat Commun
January 2025
School of Nuclear Science and Technology, Key Laboratory of Precision and Intelligent Chemistry, National Synchrotron Radiation Laboratory, School of Chemistry and Materials Science, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, PR China.
Solar-driven, selective biomass hydrogenation is recognized as a promising route to renewable chemicals production, but remains challenging. Here, we report a TiO supported Cu single-atom catalyst with a four-coordinated Cu-O structure, which can be universally applied for solar-driven production of various renewable chemicals from lignocellulosic biomass-derived platform molecules with good yields using green methanol as a hydrogen donor, to address this challenge. It is significant that the biomass upgrading driven by natural sunlight on a gram scale demonstrates the great practical potential.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Ecology and Environment, Zhengzhou University, 100 Kexue Avenue, Zhengzhou 450001, PR China; Henan International Joint Laboratory of Water Cycle Simulation and Environmental Protection, Zhengzhou 450001, PR China. Electronic address:
The efficient removal of Mn(II) from wastewater is crucial for safeguarding water quality, yet existing adsorbents face significant challenges, including high costs, poor resistance to ionic interference, and scalability limitations. This study addresses these challenges by utilizing abundant natural sandy sediment (SS) as a substrate to load unsaturated MnO via in-situ oxidation, creating a novel adsorbent (MOSS). MOSS exhibits a remarkable Mn(II) adsorption capacity of 1.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Grundlagen von Energiematerialien, Institut für Physik, Technische Universität Ilmenau, 98693 Ilmenau, Germany.
To date, III-V semiconductor-based tandem devices with GaInP top photoabsorbers show the highest solar-to-electricity or solar-to-fuel conversion efficiencies. In photoelectrochemical (PEC) cells, however, III-V semiconductors are sensitive, in terms of photochemical stability and, therefore, require suitable functional layers for electronic and chemical passivation. GaN films are discussed as promising options for this purpose.
View Article and Find Full Text PDFChem Asian J
January 2025
Kyoto University - Uji Campus: Kyoto Daigaku - Uji Campus, Institute for Chemical Research, Gokasho, 611-0011, Uji, JAPAN.
The development of efficient electron-collecting monolayer materials is desired to lower manufacturing costs and improve the performance of regular (negative-intrinsic-positive, n-i-p) type perovskite solar cells (PSCs). Here, we designed and synthesized four electron-collecting monolayer materials based on thiazolidinone skeletons, with different lowest-unoccupied molecular orbital (LUMO) levels (rhodanine or thiazolidinedione) and different anchoring groups to the transparent electrode (phosphonic acid or carboxylic acid). These molecules, when adsorbed on indium tin oxide (ITO) substrates, lower the work function of ITO, decreasing the energy barrier for electron extraction at the ITO/perovskite interface and improving the device performance.
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