Investigation into aggregation types in a benzodithiophene-isoindigo copolymer.

The type of aggregation in conjugated polymers determines their use in electronic devices. H-type aggregates are most suitable for solar cell applications, while J-type aggregates are recommended for light-emitting diodes. In this work, we used three methods to determine the type of aggregates in a benzodithiophene-isoindigo-based (PBDTI-DT) copolymer, namely, Huang-Rhys factor evolution with temperature, Franck-Condon analysis, and relative quantum yield (QY) calculation. All three methods indicate that both aggregation types are present, and the QY calculation clearly indicates that H-aggregates are more dominant. Time-dependent density functional theory was used to identify the two absorption bands of PBDTI-DT as local π - π* and intramolecular charge-transfer transitions.

g-C3N4-Co3O4 Z-Scheme Junction with Green-Synthesized ZnO Photocatalyst for Efficient Degradation of Methylene Blue in Aqueous Solution.

A simple wet chemical ultrasonic-assisted synthesis method was employed to prepare visible light-driven g-C3N4-ZnO-Co3O4 (GZC) heterojunction photocatalysts. X-ray diffraction (XRD), scanning electromicroscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), ultraviolet (UV), and electrochemical impedance spectroscopy (EIS) are used to characterize the prepared catalysts. XRD confirms the homogenous phase formation of g-C3N4, ZnO, and Co3O4, and the heterogeneous phase for the composites. The synthesized ZnO and Co3O4 by using cellulose as a template show a rod-like morphology. The specific surface area of the catalytic samples increases due to the cellulose template. The measurements of the energy band gap of a g-C3N4-ZnO-Co3O4 composite showed red-shifted optical absorption to the visible range. The photoluminescence (PL) intensity decreases due to the formation of heterojunction. The PL quenching and EIS result shows that the reduction of the recombination rate and interfacial resistance result in charge carrier kinetic improvement in the catalyst. The photocatalytic performance in the degradation of MB dye of the GZC-3 composite was about 8.2-, 3.3-, and 2.5-fold more than that of the g-C3N4, g-C3N4-ZnO, and g-C3N4-Co3O4 samples. The Mott-Schottky plots of the flat band edge position of g-C3N4, ZnO, Co3O4, and Z-scheme g-C3N4-ZnO-Co3O4 photocatalysts may be created. Based on the stability experiment, GZC-3 shows greater photocatalytic activity after four recycling cycles. As a result, the GZC composite is environmentally friendly and efficient photocatalyst and has the potential to consider in the treatment of dye-contaminated wastewater.

Experimental and computational study of metal oxide nanoparticles for the photocatalytic degradation of organic pollutants: a review.

Photocatalysis is a more proficient technique that involves the breakdown or decomposition of different organic contaminants, various dyes, and harmful viruses and fungi using UV or visible light solar spectrum. Metal oxides are considered promising candidate photocatalysts owing to their low cost, efficiency, simple fabricating method, sufficient availability, and environment-friendliness for photocatalytic applications. Among metal oxides, TiO2 is the most studied photocatalyst and is highly applied in wastewater treatment and hydrogen production. However, TiO2 is relatively active only under ultraviolet light due to its wide bandgap, which limits its applicability because the production of ultraviolet is expensive. At present, the discovery of a photocatalyst of suitable bandgap with visible light or modification of the existing photocatalyst is becoming very attractive for photocatalysis technology. However, the major drawbacks of photocatalysts are the high recombination rate of photogenerated electron-hole pairs, the ultraviolet light activity limitations, and low surface coverage. In this review, the most commonly used synthesis method for metal oxide nanoparticles, photocatalytic applications of metal oxides, and applications and toxicity of different dyes are comprehensively highlighted. In addition, the challenges in the photocatalytic applications of metal oxides, strategies to suppress these challenges, and metal oxide studied by density functional theory for photocatalytic applications are described in detail.

Optimization of preparation parameters of ceramic pot water filters for potential application of microbial and fluoride removal from groundwater.

The need to make clean water accessible and affordable for low-income countries is crucial. This study examines the suitability of various clays for Ceramic Pot Water Filters production and groundwater treatment for effective microbe and fluoride removal. For this study, three clays were collected from different geographical locations in Ethiopia,i.e., Hosaenna Clay, Babawuha Clay, and Leku Clay. Organic additives such as sawdust and eragrostis tef husks were used to increase the porosity of the Ceramic Pot Water Filters. The Atterberg limit and particle size distribution tests revealed that BC and HC have moderate to high plasticity and mouldability, making them suitable for CPWF production. The clay chemical composition, phase analysis, and thermal properties were determined using XRF, XRD, and TGA/DTA. The turbidity, fluoride level, total dissolved solids, and pH of the groundwater decreases, from 13 to 0.45 NTU, from 3.4 to 0.053 mg/100 mL, from 1245 to 360 mg/l, and from 8.4 to 7.3, respectively; all of which are within the acceptable range of WHO drinking water standards. Microbial removal tests show that the CPWFs removed 99.3%-100% of total coliform bacteria and 98.48%-100% of fecal coliform bacteria from groundwater. Therefore, this work paves the way to fabricate a clay-based ceramic water filter for low-income countries to provide affordable household groundwater treatment technology for microbial and excess fluoride removal.

Identifying surface degradation, mechanical failure, and thermal instability phenomena of high energy density Ni-rich NCM cathode materials for lithium-ion batteries: a review.

Among the existing commercial cathodes, Ni-rich NCM are the most promising candidates for next-generation LIBs because of their high energy density, relatively good rate capability, and reasonable cycling performance. However, the surface degradation, mechanical failure and thermal instability of these materials are the major causes of cell performance decay and rapid capacity fading. This is a huge challenge to commercializing these materials widely for use in LIBs. In particular, the thermal instability of Ni-rich NCM cathode active materials is the main issue of LIBs safety hazards. Hence, this review will recapitulate the current progress in this research direction by including widely recognized research outputs and recent findings. Moreover, with an extensive collection of detailed mechanisms on atomic, molecular and micrometer scales, this review work can complement the previous failure, degradation and thermal instability studies of Ni-rich NMC. Finally, this review will summarize recent research focus and recommend future research directions for nickel-rich NCM cathodes.