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Accumulation of plastic materials in terrestrial systems threatens to contaminate food chains. The aim of the current study is to determine the impact of microplastics synthesized from PET plastics (control, 50, 250, 500, 750, 1000 mg/L) with respect to morphological, biochemical impact on Cicer arietinum using standardized 72 h assay and cytotoxicity study on Allium cepa root tips. The synthesized microplastics were characterized by Scanning Electron Microscope (SEM) and Fourier Transform Infrared spectroscopy (FTIR) studies. Germination studies clearly revealed that there is a sharp decrease in germination with increasing the concentration of microplastics. Both pigment and carbohydrate levels increased up to 500 mg/L concentration, although protein levels increased with increase of microplastic dose. Catalase activity also increased with increasing microplastic concentration. Finally, cytotoxicity studies revealed significant chromosomal aberration at higher dose of microplastics. Therefore, it may be concluded that the microplastics have significant biological and structural adverse effects on plant metabolism. [Display omitted] • Synthesis of microplastics from PET plastics and characterization by SEM and FTIR. • Microplastics interfere in germination of Cicer arietinum. • Level of reactive oxygen species increased with increasing microplastic load. • Cytotoxicity study revealed significant chromosomal aberration. [ABSTRACT FROM AUTHOR]

Metal oxide nanocomposite sensors based on γ-Fe 2 O 3 and WO 3 were investigated in acetone vapor of various concentrations (1–100 ppm) at operating temperatures between 250 and 350 °C. The composites were prepared by simple solid state mixing and porous thick-film gas sensors were fabricated on alumina substrates. The γ-Fe 2 O 3 :WO 3 (50:50) nanocomposite showed a marked enhancement in sensing response down to 1 ppm acetone vapor detection at 300 °C. The response was ~2-fold better compared to pure WO 3 or pure γ-Fe 2 O 3 with a very fast response (1 s) and very short recovery time (3 s). No appreciable sensitivity was observed towards alcohol vapor (an interfacing agent for diabetics) and in moisture (present in breath). The enhanced performance was due to n–n heterojunction effect. [ABSTRACT FROM AUTHOR]

• A ternary nanocomposite containing 3 wt% rGO decorated ZnO-SnO 2 was prepared using a facile sol-gel procedure. • Pristine ZnO-SnO 2 nanocomposite sensor exhibited ~ 60% response towards 10 ppm acetone at operating temperature of 300°C. • ~3wt% rGO addition enhanced the response upto ~ 91% for 10 ppm acetone as well as operating temperature reduced to 150°C. • rGO decorated sensor was capable to detect very low concentration (~1 ppm) of VOCs with fast response and recovery time. • The sensor shows reproducible performance over time with negligible sensing response in other reducing gases. [Display omitted] A ternary p-n-n heterojunction has been prepared by introducing reduced graphene oxide (rGO) in ZnO-SnO 2 nanocomposite and its ppm level volatile organic compounds (VOCs) sensing properties have been exploited. Using a simple, facile sol-gel process, initially, ZnO-SnO 2 nanocomposites containing different concentrations of ZnO and SnO 2 were prepared and subsequently this was followed by rGO incorporation. The as-synthesized powders were well characterized through XRD, FTIR, Raman spectroscopy, FESEM, TEM, and XPS analyses. The sensing study revealed that, the ternary nanocomposite sensor delineated ~91% n-type sensing response towards ~10 ppm acetone gas at an optimum working temperature of 150 °C. Even it could sense ~1 ppm acetone with appreciable sensing response of ~71%. Additionally, the sensor displayed fast response (~10 s) and recovery time (~100 s) suitable for detection of multiple pulses in short time duration. It also exhibited a considerable ~65% sensing response towards ~10 ppm ethanol at 150 °C. These superior sensing performances of rGO decorated ZnO-SnO 2 nanocomposite illustrated with band structure modification. Our results indicated that, the fabricated rGO decorated ZnO-SnO 2 sensor, with remarkable high sensing response, minimum interference from other toxic, inflammable gases and profound long term stability, could be considered as a prolific candidate for real time detection of low concentration VOCs in versatile commercial applications. [ABSTRACT FROM AUTHOR]

• An improved rGO incorporated WO 3 based electrochromic film was developed using a facile sol-gel dip-coating procedure. • 5wt% rGO composition demonstrated the maximum electrochemical performance along with 50% transmittance modulation. • ∼ 45% enhancement in the switching response time and a significant improvement in coloration efficiency were also obtained. • The observed better electrochemical cyclic stability of rGO-WO 3 film was analyzed using ex-situ XRD analysis. • The EIS study of pristine and rGO decorated films revealed enhanced charge transfer on incorporation of rGO. In the present work, an improved electrochromic thin film has been developed with faster color switching time on incorporation of rGO in WO 3 film. Here, pristine WO 3 and rGO-WO 3 (rGO concentration varying from 1–7wt%) based nanocomposite electrochromic films were fabricated on ITO coated glass substrate, by utilizing a facile sol-gel dip-coating technique. Detailed structural and morphological analyses of the films were carried out using XRD, FESEM, TEM and Raman Spectroscopy. Assimilating the electrochromic properties of all the films showed that, 5wt% rGO incorporated WO 3 film gave a maximized electrochemical performance with minimum degradation in optical transmittance. The film also exhibited an optical modulation of ∼ 50% and a better switching response having coloration time (t c) ~ 5.3 s and bleaching time (t b) ~ 6.2 s as compared to the pristine film (t c ~ 9.6 s, t b ~ 10.4 s). Incorporation of rGO also resulted in an enhancement of coloration efficiency from ∼ 81 to ∼ 386 cm2/C. The Electrochemical Impedance Spectroscopy (EIS) analysis of pristine and rGO loaded film clearly revealed better charge transfer on incorporation of rGO. The cyclic stability study exhibited ∼ 25% deterioration in optical transparency of the bare WO 3 film which was < 10% for the rGO impregnated film. An ex-situ XRD analysis demonstrated that a crystal dislocation occurring in pristine WO 3 sample was responsible for the same. [Display omitted]. [ABSTRACT FROM AUTHOR]