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The continuous rise in atmospheric CO2 concentration, overconsumption of energy resources, and release of extraordinary organic pollutants are challenging issues of the modern era. Catalytic technology offers a promising solution to tackle these energy and environmental challenges in parallel by facilitating highly effective and sustainable processes. Herein, we report the fabrication of a series of different nature polyarylimide (PAI)-based covalent–organic frameworks (COFs) via the polycondensation reaction by altering linkers, organic solvents, and other experimental conditions. To optimize their catalytic performance, the resultant PAI-COFs were further decorated with metal–organic frameworks (ZIF-67). The decoration of COF4 with ZIF-67 led to adjusted bandgaps, created an active site, enhanced charge separation and migration of photoexcited electron–hole (e–h) pairs, extended the light absorption to the visible region, and also facilitated the transferring of electrons between the COFs and MOFs via the photoelectron modulation approach. Based on our findings, it is confirmed that COF4 and ZIF-67 (MOFs) are the optimal catalysts compared to the other COFs (COF1, COF2, and COF3) and MOFs (ZIF-8). Interestingly, compared to the pristine COF4, the 5ZIF-67/COF4 nanohybrid revealed ∼8-fold and ∼5.3-fold for CO2 conversion, direct CO2 capturing, and photoelectrochemical CO2 conversion with a faradaic efficiency of 50%. Likewise, the as-fabricated catalyst also exhibits exceptional activities for photocatalytic hydrogen production and pollutant oxidation. Ultimately, this work will provide a roadmap for the design and fabrication of COF-based nanohybrids for energy and environmental applications. [ABSTRACT FROM AUTHOR]

In this research study an eco-friendly approach is utilized to synthesize the green g-C3N4 based nanocomposites by employing Zingiber officinale as stabilizer and mediator. Our results proved that the green g-C3N4 have good performances and exceptional visible light photocatalytic activities as compared to the chemically synthesized g-C3N4. The small surface area, and low charge separation of g-C3N4 is upgraded by coupling with TiO2 nanoparticles. Our experimental results have confirmed that Zingiber officinale worked as stabilizer and mediator, while the coupling of TiO2 worked as facilitator and photoelectron modulator to enhance the charge separation. Compared to pristine green g-C3N4 (GCN), the most active sample 5Ti/GCN showed ~ 2.5-fold improvement in photocatalytic activities for sulfadiazine and bisphenol A degradation. The degradation pathways of sulfadiazine and bisphenol A showed the mineralization steps and production of less hazardous and small molecules (CO2 and H2O). Finally, our current novel research work will provide a new gateway to synthesize the plant assisted and eco-friendly green nanomaterials and its employment for pollutants degradation and environmental purification. Graphical abstract representing the Zingiber officinale mediated synthesis of TiO2 coupled g-C3N4 green nanocomposites [ABSTRACT FROM AUTHOR]

Environmental protection laws require effective and green solutions to tackle water and air pollution issues. For this purpose, perovskite photocatalytic materials have proven to be a promising solution. In this study, CsSnBr3 perovskite, coupled with ZIF-67 and decorated with noble metal Au, was shown to effectively enhance the charge separation and increase the light-absorbing capacity, and thus make the photocatalytic reaction more efficient by surface plasmon resonance. Characterization results from XRD, FTIR, and UV-visible diffuse reflectance spectroscopy indicated that a mixture of cubic and tetragonal crystalline phases was found in the prepared catalyst material. XPS also revealed that in the presence of two oxidation states for tin (Sn), the Au 4f XPS peaks of Au NPs coincided with those retained in colloidal Au particles. Using malachite green as a model compound, organic pollutant photocatalytic degradation tests proved that CsSnBr3 generated good photocatalytic activity for aromatic pollutant degradation. In this research, the synthesized 4Au-7ZIF-CsSnBr3 catalyst yielded an MG degradation rate twice as high as the unpromoted CsPbBr3. [ABSTRACT FROM AUTHOR]

This study examines perception of voters in Peshawar district about electronic voting system for building pubic trust in the electoral process. The evaluation was made based on its utility, its role in reducing electoral malpractices, improving reliability, voter recognition, and discouraging vote buying. The study is quantitative, and its scope is limited to the district of Peshawar. The information was gathered via a questionnaire from 400 respondents in the Peshawar District using convenience sampling. The frequency, percentage, and chi-square tests were used to analyse the data. The data was further refined by incorporating various independent variables such as area, gender, age, and literacy. [ABSTRACT FROM AUTHOR]