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Since India is one of the most populated countries in the world, there is a constant increase in the demand for food supply. To cater to the increased demand, the farmers use agrochemicals for crop protection and to enhance crop yield. Prolonged use of these agrochemicals, contaminates the groundwater, soil, and air, causing damage to our ecosystem and having adverse effects on human health. The present study reports the one‐pot synthesis of graphene‐CdS (GC) nanocomposites by a facile thermal decomposition approach. Thermal decomposition is an easy and cost‐effective technique. It's a facile and more efficient method than other methods. The synthesized graphene‐CdS nanocomposites were characterized using XRD, FT‐IR spectroscopy, Diffuse Reflectance Spectroscopy, RAMAN spectroscopy, and FE‐SEM analysis. The potential of GC nanocomposites has been explored as an efficient photocatalyst for the degradation of chlorpyrifos (CPY) in an aqueous solution. It was observed that the nanocomposites exhibit 89 % degradation efficiency in 90 minutes compared to the pristine CdS and Graphene. A detailed investigation of the degradation pathway and scavenger studies were also conducted. The Graphene‐CdS hold scope and potential to be explored as an effective photocatalyst for the mineralization of agrochemicals. [ABSTRACT FROM AUTHOR]

The rapid development of the industrial world causes wastewater containing dyes to continue to increase. Even in recent years, the food, textile, cosmetic, plastic, and printing industries have developed the use of dyes. Methylene blue (MB) is one of the cationic dyes widely used in dyeing silk, wood, and cotton because of its absorbency and good fastness to materials. The adsorption process is the best technique and preferred in removing dyes from wastewater due to excellent selectivity, high efficiency from high-quality treated effluent, flexibility in design, and simplicity. Therefore, there is a growing interest to identify low-cost alternative adsorbents that have reasonable adsorption efficiency, especially natural materials such as leaves. In this study, research on MB adsorption using leaves was analyzed using bibliometric analysis. Information of bibliometric is extracted from the Scopus database with the keyword "Methylene Blue", "Adsorption or Desorption", and "Leaves or leaf". The results showed that India, Desalination and Water Treatment, and SASTRA Deemed University were the country, journal, and institution that contributed the most publications on this topic. Therefore, it is expected that with the use of bibliometrics, the use of leaf-based MB adsorption processes in their potential for MB dye removal can be investigated especially for large-scale development. [Display omitted] • Adsorption is more promising for large-scale development than photocatalytic degradation. • Adsorbent based on leaves needs further research, especially from a techno-economic perspective. • The first bibliometric study on MB adsorption using leaves was reported. • The high frequency of "adsorption" and "methylene blue" for the research hotspot. [ABSTRACT FROM AUTHOR]

Recent reports on nanoparticles rise significantly as they possess numerous applications in medical, material science, optics, and bioscience etc. Nanoparticles show unique properties as they are an inter-linker between bulk materials and atomic structures. On behalf of large surface area of nanoparticles, they are utilized to a greater extent that leads to contribute in making small bulk of the nanoparticles. Varieties of procedures are already reported but they have too much drawbacks like release of toxic by-products that are hazardous to the environment. To address all these problems, greener method such as plant extract was introduced. In India, Glycyrrhiza glabra, a small traditional perennial herb was used to cure sore throat, cough, ulcers and hepatitis. Hence, the aforementioned plant extract was used to synthesize ZnO nanoparticles. The green synthesized ZnO nanoparticles were analysed to study their morphology and other salient characters by the utilization of UV-Vis spectroscopy, FT-IR, SEM and TEM analysis. In this present study, utilization of this green synthesized ZnO NPs in the photo degradation of azo dyes (Congo red and amaranth dyes) and kinetic expressions were reported. These findings revealed good photocatalytic activity against the azo dyes (Congo red and Amaranth dyes) and an excellent photocatalyst for Congo red dye degradation. This synthetic approach is environmental friendly and can provide new techniques in the management of pollutants. [ABSTRACT FROM AUTHOR]

Abstract: Polychlorinated naphthalenes (PCNs) are now under review by the Stockholm Convention as candidates for persistent organic pollutants (POPs) due to their persistence, toxicity, bioaccumulation, and long-range atmospheric transport. Data on PCN levels are sparse in South Asia. Atmospheric PCNs in India and Pakistan were monitored during the winter by polyurethane foam disk passive air samplers (PUF-PAS). The average concentrations were 29pg/m3 and 7.7pg/m3 in the Indian and Pakistani samples, respectively. Those concentration levels were relatively lower than the previously reported values in other Asian countries, but still considerably higher than in other sites in the world. Tri-CNs and tetra-CNs were the dominant homologues in the air, especially in India. Spatially, the PCNs were ubiquitous in the target areas, and local distribution was generally impacted by the proximity to potential sources. Major sources of PCNs in this study were the re-emission of Halowax and industrial thermal processes. Biomass burning influenced some sites in Pakistan. However, the enrichment of tri-CNs in Indian cities cannot be ascribed to either the signature of a specific source or the preferential volatilization and/or photodegradation in tropical areas. Despite this unclear issue in South Asia, the present study indicates that the potential health impact was generally comparable to that in non-urban sites worldwide. [Copyright &y& Elsevier]

Herein, a green and facile methodology was used for the structural design of semiconductor nanomaterials and employed as efficient photocatalyst to resolve the environmental issues of water pollutants. Titanium oxide coupled with bismuth oxide (TiO 2 @Bi 2 O 3) nanocomposite was synthesized by employing the seed extract of Sapindus mukorossi (commonly found plant in India) and subsequently used for the elimination of toxic, and persistence industrial pollutants namely bisphenol A (BPA) and methylene blue (MB). Microscopic and spectroscopic techniques revealed particle size of synthesized nanocomposite found less than 50 nm along with high crystallinity. Appearance of stretching vibrations at 459 cm−1 for Bi–O–Ti in the IR spectra of nanocomposite has established the coupling of TiO 2 with Bi 2 O 3. The parameters of degradation were optimized by varying the pollutant concentration, catalytic amount and pH in the presence of natural sunlight. The nanocomposite TiO 2 @Bi 2 O 3 showed maximum degradation (MB: 94% and BPA: 91%) at a minimum concentration of pollutant (50 mgL−1) with catalyst amount (35 mg), neutral pH and reduces half-life of pollutants (BPA: 1h, MB: 0.5h). Owing of higher surface area (80 m2g-1), lower band gap (2.5 eV), and more negative zeta potential value (−40.3 mV) results into excellent photocatalytic properties. The breakage of S–N conjugated system in MB results into rapid degradation as compare to BPA. The degradation followed first-order kinetics and Langmuir adsorption in both the cases. Presence of active radicals during the photocatalysis process was responsible for quick degradation and strongly supported by scavenger analysis. GC-MS analysis revealed the degradation of toxic pollutants into safer metabolites and finally mineralized. Multiple times (n = 8) reusability of green photocatalyst advocated sustainability and appropriate for industrial applications. [Display omitted] • Natural extract based synthesis of TiO 2 @Bi 2 O 3 nanocomposite. • First-order degradation of Bisphenol A (91%) and Methylene Blue (MB) dye(9 4%) by TiO 2 @Bi 2 O 3. • Optimization of concentration, pH, catalyst dose and source of irradiation. • Hybrid nanostructure increased charge separation and prevent e−/h + recombination behavior. • Small non-toxic by-products and excellent reusability (8th cycle) confirm high efficiency. [ABSTRACT FROM AUTHOR]