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The abolition of environmental pollutants and production of hydrogen (H2) from water using a heterogeneous photocatalyst is a demanding science of the current scenario to solve the increasing environmental pollution and worldwide energy catastrophe in modern life. To validate this purpose, the design of low-cost and durable semiconductor-based photocatalysts with great light absorption capacity becomes the most challenging issue for researchers. Regarding this, herein the phosphotungstic acid (HPW)-anchored Zr6O4(OH)4(BDC)6 (UiO-66) metal–organic framework (MOF), i.e., HPW@UiO-66, has been prepared by a hydrothermal method and is efficient, stable, and capable of harvesting solar energy toward the degradation of tetracycline hydrochloride (TCH) and H2 production in the presence of a sacrificial donor. The ionic interaction between HPW and UiO-66 plays a key role toward the photostability and charge-transfer mechanism of the composite and is well characterized with X-ray diffraction, UV diffuse-reflectance spectroscopy, Fourier transform infrared, and X-ray photoelectron spectroscopy. A total of 30 wt % HPW@UiO-66 shows a maximum degradation of about 87.24% of a 20 ppm TCH solution in 60 min of solar-light irradiation and about 353.89 μmol/h of H2 production. The conduction- and valence-band potentials are well characterized with Mott–Schottky measurement and a delay charge recombination process through electrochemical impedance spectroscopy. The proposed mediator-free Z-scheme-oriented electron–hole migration route is well supported by photoluminescence, and the scavenger test well explains the better charge-carrier separation and high catalytic performance of the prepared composite. This research will bestow an advantageous blueprint to fabricate novel and challenging photocatalysts toward the photocatalytic treatment of environmental pollutants and H2 evolution.

Paper-based microfluidic devices are rapidly becoming popular as a platform for developing point-of-care medical diagnostic tests. However, the design of these devices largely relies on trial and error, owing to a lack of proper understanding of fluid flow through porous membranes. Any porous material having pores of multiple sizes contains partially saturated regions, i.e., regions where less than 100% of the pores are filled with fluid. The capillary pressure and permeability of the material change as a function of the extent of saturation. Although methods to measure these relationships have been developed in other fields of study, these methods have not yet been adapted for paper for use by the larger community of analytical chemists. In the current work, we present a set of experimental methods that can be used to measure the relationships between capillary pressure, permeability, and saturation for any commercially available paper membrane. These experiments can be performed using commonly available lab instruments. We further demonstrate the use of the Richards equation in modeling imbibition into two-dimensional paper networks, thus adding new capability to the field. Predictions of spatiotemporal saturation from the model were in strong agreement with experimental measurements. To make these methods readily accessible to a wide community of chemists, biologists, and clinicians, we present the first report of a simple protocol to measure the flow rates considering the effect of partial saturation. Use of this protocol could drastically reduce the trial and error involved in designing paper-based microfluidic devices.

The current study on Au/Pd@UiO-66-NH2 explores a novel approach towards photocatalytic SMC coupling reaction. This investigation highlights a well studied mechanistic pathway towards the formation of biphenyl as the target product.

The SPR effect of monodisperse Ag nanoparticles in Ag@Ag3VO4/ZnCr LDH heterostructures exhibits high photocatalytic activity towards evolution of O2 and oxidation of phenol.

This review focuses on the possible mechanisms involved in the organic transformations occurring through photocatalysis over functionalised metal–organic frameworks.

The paper reports preparation, surface, and textural characterization of Cu and Ni modified MCM-41 and its application for hydrodehalogenation of chlorobenzene. A series of Cu/Ni modified MCM-41 samples were synthesized by the co-condensation method by varying the amount of Ni and further characterized by various physicochemical methods. The incorporation of metals in the framework of mesoporous silica matrix was confirmed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies showed the formation of uniform spherical particles on the support surface. The catalytic activity of the samples was evaluated toward the hydrodehalogenation reaction of chlorobenzene at room temperature. Samples containing Si/(Cu + Ni) = 10 showed the highest chlorobenzene (98%) conversion with 100% selectivity for benzene. Among the various solvents studied for the reaction, isopropyl alcohol gave the best results at 2 h of reaction time. The effect of various halogen substituent and different electron donating and withdrawing groups on chlorobenzene is also studied to optimize the reaction conditions.

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