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The photocatalytic production of fuels and chemicals utilizing highly effective catalysts has garnered a lot of interest as a sustainable and clean strategy. Herein, we have reported the effective fabrication of an imine-linked covalent organic framework, FP-BTA COF, supported 2D–2D MoS2/FP-BTA heterojunction with molybdenum sulfide (MoS2) utilizing an easy hydrothermal technique. The development of a 2D–2D heterojunction between a covalent organic framework (COF) and molybdenum sulfide (MoS2) with well-matched band positions can efficiently restrict the recombination of the charge carriers and boost the light absorption capacity along with the surface area, which is mainly responsible for the greatly improved catalytic efficiency. This as-prepared MoS2/FP-BTA hybrid photocatalyst demonstrated exceptional dual catalytic efficiency for the oxidative coupling of benzylamine derivatives to generate higher yields (92%) of N-benzylidene benzylamines along with selective reduction of carbon dioxide (CO2) to formic acid (highest generation rate = 43.3 mol gcat−1 h−1) at atmospheric carbon dioxide (CO2) pressure as compared to molybdenum sulfide (MoS2) and the FP-BTA COF without the requirement of any extra sacrificial electron donors under sunlight. The present research also focuses on economically viable, straightforward and sustainable methods for visible-light induced oxidation of a sequence of benzylamines under atmospheric oxygen (O2) utilizing the MoS2/FP-BTA hybrid material and the highest 98% isolated yield of the product containing a mixture of the corresponding imine and carbonyl compounds was achieved under ambient reaction conditions. The photocatalyst produced a good amount of the intended products and was easily recoverable and recyclable up to the fifth run for both reactions. The creation of a single hybrid with a 2D–2D interface by fusing organic and inorganic materials as well as the twin strategy of producing valuable chemicals in a single process may open up new prospects for sustainable development and enhance the atom economy. [ABSTRACT FROM AUTHOR]

The article presents the discussion on significance of groundwater (GW) globally and its management challenges, particularly focusing on India's situation. Topics include highlights the over-exploitation of groundwater resources in India, emphasizing the need for sustainable management practices to address water security issues; and global groundwater significance, challenges in groundwater management, and India's groundwater situation.

Dual-emissive protein-capped metal nanoclusters are emerging nanoprobes for ratiometric sensing. Here, we report dual-emissive bovine serum albumin (BSA)-capped silver nanoclusters (AgNCs) with a blue emission band at 450 nm and a far-red emission band at 680 nm. The blue emission is attributed to the BSA capping, while the far-red emission originates from the AgNCs. The intensity ratio of the two bands is susceptible to the presence of IO4– and Cu2+, allowing selective detection of these analytes with a limit of detection (LOD) of 18.8 and 21.6 nM, respectively. These two analytes display different effects on the emission bands. The blue emission band increases with simultaneous diminution of the far-red band in the presence of IO4–; however, only the far-red emission band decreases in the presence of Cu2+ without altering the blue emission. Both the analytes manifested distinct visual changes in the emission color of the AgNCs solution under a UV lamp, which can also be evident from the shift of the Commission Internationale d'Eclairage (CIE) coordinates from (0.48, 0.32) to (0.18, 0.17) and (0.24, 0.25) for IO4– and Cu2+, respectively. IO4– induced a conformational change in BSA, intensifying the blue emission band along with a dynamic quenching of the AgNCs' emission at 680 nm. In contrast, Cu2+ triggered only a metal exchange method-based quenching of the 680 nm emission with almost no effect on the BSA capping. A smartphone-based on-site detection of IO4– and Cu2+ was also achieved. Inspired by the contrasting fluorescence (Fl) response signals of AgNCs toward IO4– concentration, a simple logic gate circuit was constructed. This investigation will provide important insight into the one-pot synthesis of dual-emissive silver nanoclusters and the ratiometric detection mechanism of IO4– and Cu2+. [ABSTRACT FROM AUTHOR]

Abstract We present a very simple and effective way for the synthesis of tunable coloured silver sols having different morphologies. The procedure is based on the seed-mediated growth approach where methyl cellulose (MC) has been used as soft-template in the growth solution. Nanostructures of varying morphologies as well as colour of the silver sols are controlled by altering the concentration of citrate in the growth solution. Similar to the polymers in the solution, citrate ions also dynamically adsorbed on the growing silver nanoparticles and promote one (1-D) and two-dimensional (2-D) growth of nanoparticles. Silver nanostructures are characterized using UV–vis and HR-TEM spectroscopic study. Simulation of the UV–vis extinction spectra of our synthesized silver nanostructures has been carried out using discrete dipole approximation (DDA) method.

Dual-emissive carbon dots (D-CDs) are in high demand for multipurpose applications. Herein, nitrogen-doped carbon dots possessing inherent dual emissions at green (490 nm) and yellow (570 nm) are synthesized hydrothermally from 3,4-diaminobenzoic acid and hydrazine hydrate. The relative intensity of the two emission bands is dependent markedly on the pH of medium, making the D-CDs a robust pH sensor within the pH range of 2.0–7.6. The ratiometric emission of D-CDs is sensitive to trace amounts of Fe3+; the 490 nm emission intensity diminishes with simultaneous amplification of the 570 nm emission intensity. A discernible color change from light green to bright yellow is evident under an ultraviolet (UV) lamp with increasing Fe3+ concentrations, and the CIE color coordinate shifts from (0.33, 0.43) to (0.47, 0.50). Primarily, the complexation between D-CDs and Fe3+ and the accompanying aggregation play a dominant role in the ratiometric change of the emission intensities. For the on-spot detection of Fe3+, smartphone-based and solid-phase sensing is accomplished. The D-CDs also display decent anticancer properties against the breast cancer cell line MCF-7 and effectively detect the intracellular pH and exogenous Fe3+ inside the MCF-7 cells. [ABSTRACT FROM AUTHOR]