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The present work demonstrates an innovative strategy for robust water purification using an engineered aerogel membrane fabricated from biopolymers and task-specific Fe−Al-based nanocomposites. The as-prepared ethylenediaminetetraacetate dianhydride cross-linked chitosan-and agarose (7:3 weight ratio)-based aerogel membrane decorated with α-FeOOHand γ-AlOOH-based nanocomposites was characterized using various analytical tools, which suggested formation of a highly stable network interconnected through covalent and electrostatic interactions. The optimized bionanocompositebased aerogel (BNC-AG-0.1) membrane showed macroporous and partial unidirectional short-range channels with an ultralow density of 0.021 g•m −2 , a high swelling ratio of 1974%, and a remarkable pure water flux of 19,228 L•m −2 •h −1 (>6-fold higher flux compared to the reported aerogel membranes). The aerogel membranes were successfully utilized for purification of diverse pollutants such as dyes, emerging pollutants (EPs), arsenate, and fluoride in a continuous flow method under gravitational force. The BNC-AG-0.1 membrane exhibits high rejection (95−98.6%) for both cationic and anionic dyes with a flux rate of 1150−1375 L•m −2 •h −1 and a rejection of 89−92% for EPs with a flux rate of 1098−1165 L•m −2 •h −1 . Moreover, the BNC-AG-0.1 membrane showed a q max of 102.45 mg•g −1 (at pH 6.5) for As(V) with >93% rejection at a flow rate of 1000 L•m −2 •h −1 . Furthermore, the aerogel membrane showed an excellent removal efficiency (92%) of arsenic up to the 10th cycle and hence demonstrated as a potential adsorption-based membrane for arsenic-free potable water. On the other hand, the BNC-AG-0.1 membrane showed a q max of 81.56 mg•g −1 (at pH 6.5) for F − removal with >99% rejection at a flow rate of 250 L•m −2 •h −1 . When applied for real-water purification, approximately 4734 L of safe drinking water (the F − concentration is less than the WHO permissible limit) per square meter of the aerogel membrane can be obtained with a flux rate of 250 L•m −2 •h −1 . Overall, the prepared aerogel membrane showed robust removal of a variety of contaminants with ultrafast water permeation and established excellent recyclability.

A dysprosium (Dy3+)‐activated potassium calcium silicate (K4CaSi3O9) phosphor was prepared using a solid‐state synthesis route. The phosphor had a cubic structure with the space group Pa as confirmed using X‐ray diffraction (XRD) measurements. Details of surface morphology and elemental composition of the as‐synthesized undoped KCS phosphor was obtained using scanning electron microscopy (SEM) and energy‐dispersive X‐ray (EDX) spectroscopy. The chemical structure as well as the vibrational modes present in the as‐prepared KCS phosphor was analyzed using Fourier transform infrared (FT‐IR) spectroscopy. Diffuse reflectance spectra (DRS) were used to determine the optical bandgap of the phosphors and were found to be in the optical range 3.52–3.71 eV. Photoluminescence (PL) spectra showed intense yellow emission corresponding to the 4F9/2→6H13/2 transition under 350 nm excitation. Commission International de l′Eclairage colour chromaticity coordinates were evaluated using the PL spectral data lie within the white region. Dexter theory and the Inokuti–Hirayama (I–H) model were applied to study the nature of the energy transfer mechanism in the as‐prepared phosphors. The relatively high activation energy of the phosphors was evaluated using temperature‐dependent PL (TDPL) data and confirmed the high thermal stability of the titled phosphor. The abovementioned results indicated that the as‐prepared KCS:Dy3+ phosphor was a promising candidate for n‐UV‐based white light‐emitting diodes.