Rajib Ghosh Chaudhuri

Bimetallic Mn‐doped MIL‐53(Fe) metal–organic framework (MOF) has been developed to remove crystal violet (CV) efficiently from wastewater through the photo‐Fenton process. The key innovation of the work lies in enhanced visible light activity, lesser H ₂ O ₂ oxidant content, and faster removal with less sludge generation. Comprehensive characterizations revealed a lower bandgap and rapid charge separation, which reflected on the improvement of the performance of the photocatalyst. The bimetallic MOF achieved 99.01% removal of CV under the visible 100 W Xe light source with six times faster rate than the pristine MIL‐53(Fe) and also 82.42% CV removal under irradiation of sunlight in 60 min at optimized conditions of 20.0 ppm dye concentration, 444 ppm H ₂ O ₂ concentration, and 1.0 g/L catalyst loading. The composite maintained good recyclability up to five consecutive cycles with a removal of 78.89% CV. The treated effluent exhibited lower toxicity in seed germination tests, demonstrating the potentiality of Mn‐doped MIL‐53(Fe) as a stable and efficient catalyst for wastewater treatment.

This work presents the synthesis of a biodegradable nano‐bio‐composite thin film using polyvinyl alcohol (PVA) and starch (ST) for food packaging. Traditional synthetic polymers create microplastics that are harmful to the environment. In contrast, biodegradable films provide a safer alternative. Using a solution casting method, we blended PVA and ST with glycerol (GL) to enhance flexibility, while incorporating titanium dioxide (TiO ₂ ) and graphitic carbon nitride (g‐C ₃ N ₄ ) as nano‐fillers. Characterization techniques employed included FTIR, SEM, TGA, UV–vis, and degradation tests. The films containing nanomaterials showed a significant reduction in water vapor transmission rates, measuring 80.03 g/m ² ·h for TiO ₂ and 78.65 g/m ² ·h for g‐C ₃ N ₄ , compared to 86.07 g/m ² ·h for the PVA/ST/GL blend. This indicates improved food preservation capabilities. Furthermore, films with g‐C ₃ N ₄ exhibited enhanced degradation rates of 85.20% in microbial environments and 26.06% in soil, compared to those without nanomaterials. This approach not only addresses the issue of microplastic pollution but also supports biodiversity while extending the shelf life of vegetables by 10 – 12 days.

The rapid growth of human society and the necessity of protecting human health and security underscore the importance of identifying the toxic gases emitted by industrial sectors. Ammonia (NH₃) is a widely produced industrial colorless toxic gas with a strong odor, coupled with its harmful environmental and health impacts, such as contributing to air pollution (PM 2.5 formation) and severe impact on the respiratory system of the human body, even at low concentrations. Covalent Organic Frameworks (COFs) have emerged as revolutionary materials to address these current issues. The crystalline porous network through the dynamic covalent chemistry of COFs possesses versatile structural and chemical properties that make them ideal for gas sensing. This review provides a comprehensive overview of the latest advancements in COF‐based gas sensors with a focus on ammonia sensing. Moreover, the detailed discussion about the structural design and synthesis methods of COFs and their important characterization techniques is presented. It concludes by providing a future outlook for developing advanced COF materials in gas sensing applications.

Environmental researchers are extremely concerned about addressing the declining availability of drinking water, which is a critical issue in many nations. Solar-driven desalination is an emerging and pioneering renewable approach to reduce potable water scarcity that is suitable for remote locations, developing countries, and disaster zones as it does not require additional energy supply. However, there are still issues with the scalable preparation of photothermal materials, such as achieving low cost and widening the assortment of useful applications. Conventional carbon- and metal-based absorbers are intricate and fragile, which make them difficult to install and transport in places with minimal infrastructure. Thus, a universal process for creating adaptable solar evaporators is sorely required. Herein, we have come up with a holistic approach using a solar absorber (GJ-01(Cal)) derived from a Cu-MOF (HKUST-1) and carbon nanosheets (CNSs) for generating potable water from saline water using solar radiation. The as-synthesized material provides high-performance photothermal water evaporation when illuminated under solar irradiation at the air–water interface. Moreover, its porous structure, high photothermal conversion efficiency, rapid water flow, and heat insulation make it appropriate for saline water desalination. CNS play a pivotal role in improving the photothermal features of the solar absorber (GJ-01(Cal)) in terms of conjugation to promote Cu(0) species and pyrrolic nitrogen (P-N) amplification and thereby enrich the p-type nature of the absorber's triphasic configuration. With these photothermal factors, the localised surface plasmon resonance (LSPR) of electrons increases and achieves high solar spectrum absorption. The GJ-01(Cal) was further coated on porous cotton fibrils (CF) that regulate photothermal interfacial evaporation (PTIE) by allowing water transportation via capillary action. This assemblage of the nanocomposite on CF efficiently evaporates water at a higher surface temperature of ∼47 °C under one solar illumination, achieving 4.23 kg m⁻² h⁻¹ of evaporation flux and 96.5% light-to-heat conversion efficiency. Interestingly, the GJ-01(Cal) coated over CF can be recycled at least 10 times. Additionally, it offers scalable production for higher photothermal efficiency with a flexible substrate as a solar evaporator and is beneficial for society paving new horizons towards a sustainable environment.

In this study, a superior nanocomposite adsorbent g-C₃N₄/MoS₂ was synthesized for the removal of an environmentally noxious pollutant rhodamine B. The nanocomposite showed fast adsorptive removal rate of more than 97% in 90 min.

Photothermal interfacial evaporation (PTIE) draws the attention of researchers owing to its eco‐friendly approach of obtaining purified potable water from unusable seawater. The salience behind this technology ensures an indispensable commodity highly accessible via implementation of localized heating principles to vaporize seawater at water/air interface, instead of excessive energy consuming bulk‐water evaporating desalination systems. The significance of any technology depends on its component, and photothermal desalination technology lies on its material. In this review, focus on ultramodern nanomembranes, Janus nanoarchitectures, and reticular materials as promising solar–thermal nanostructures is highlighted. This report aims to inspire novel advancements in nanomaterials for photothermal desalination by providing cognizance into the mechanisms of photothermal conversion and principles of capillary action to construct innovative water pathway to continuously pump water with excellent salt‐rejecting feature, thereby enhancing PTIE performance. With desalination as the focus, insights into vapor condensation for the collection of desalinated water are discussed. Furthermore, reports on innovative solar‐driven water purification projects undertaken by different countries to be in action in the near future are incorporated. Eventually, this review sheds light on some practical outlook toward the optimization of judicious nanomaterials for a sustainable tomorrow.