Eco-friendly cubic-ZnS coupled Cu7S4 spines on chitosan matrix: Unravelling defect-engineered nanoplatform for the photodegradation of p-chlorophenol.

Novel ZnS-Cu7S4 nanohybrid supported on chitosan matrix, as an ideal photocatalyst, was fabricated by the sonochemical method wherein high-resolution transmission electron microscopy (HRTEM) and X-ray powder diffraction (XRD) analysis confirmed the co-existence of both ZnS and Cu7S4; presence of vacancy sites in ZnS was verified by electron paramagnetic resonance (EPR) analysis and their introduction could promote two-photon excitation facilitated visible light response and charge transport/separation. The type II interface is formed in the ZnS-Cu7S4/Chitosan heterojunction owing to interstitial states that promote charge separation. The ZnS-Cu7S4/Chitosan was used for the photodegradation of a pharmaceutical pollutant, p-chlorophenol (PCP); over 98.8% of PCP photodegradation was achieved under visible-light irradiation where the ensued ·O2- and ·OH serve a key role in the photodegradation of PCP. In vitro cytotoxicity studies substantiated that the ZnS-Cu7S4/Chitosan is nontoxic to the ecosystem and human beings and endowed with promising photodegradation properties and accessibility via an environmentally friendly design, bodes well for its potential remediation applications.

Adsorptive removal of tetracycline from aqueous solutions using magnetic Fe2O3 / activated carbon prepared from Cynometra ramiflora fruit waste.

Herein, the sustainable fabrication of magnetic iron oxide nanoadsorbent prepared with activated carbon of inedible Cynometra ramiflora fruit has been investigated. Activated carbon was obtained from phosphoric acid-treated C. ramiflora fruit, which was then utilized for the synthesis of magnetic nanocomposite (CRAC@Fe2O3). The formed nanocomposite was a porous irregular dense matrix of amorphous evenly sized spherical nanoparticles, as visualized by FESEM, and also contained carbon, oxygen, iron, and phosphorous in its elemental composition. FT-IR spectrum depicted characteristic bands attributing to Fe-O, C-OH, C-N, CC, and -OH bonds. VSM and XRD results proved that CRAC@Fe2O3 was superparamagnetic with a moderate degree of crystallinity and high saturation magnetization value (1.66 emu/g). Superior surface area, pore size, and pore volume of 766.75 m2/g, 2.11 nm, and 0.4050 cm3/g respectively were measured on BET analysis of CRAC@Fe2O3 nanocomposite, indicating their suitability for use as an adsorbent. On application of this nanocomposite for adsorption of tetracycline, maximum removal of 95.78% of 50 ppm TC at pH 4, CRAC@Fe2O3 0.4 g/L in 240 min. The adsorption of TC by CRAC@Fe2O3 was confirmed as monolayer sorption by ionic interaction (R2 = 0.9999) as it followed pseudo-second-order kinetics and Langmuir isotherm (R2 = 0.9801). CRAC@Fe2O3 showed a maximum adsorption capacity of 312.5 mg/g towards TC antibiotics indicating its potential for the treatment of antibiotic-contaminated samples. Since negative ΔGo and positive ΔHo and ΔSo values were obtained at all tested temperatures during the thermodynamic studies, the adsorption was confirmed to be endothermic, spontaneous, and feasible with an enhanced degree of randomness.

Plasma-assisted in-situ preparation of L-cystine functionalized silver nanoparticle: An intelligent multicolor nano-sensing of cadmium and paracetamol from environmental sample.

L-cystine (L-cys) functionalized plasmonic silver nanomaterial (Ag NPs) was fabricated toward the selective and sensitive detection of paracetamol and cadmium. The prepared L-cys-Ag nanoparticles (NPs) were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD) and fourier transform infrared spectroscopy (FTIR) analyses. SEM imaging show that Ag NPs was decorated on the surface of L-cysteine 3D cubic nanosheet. L-cys-Ag NPs showed selective and sensitive detection towards paracetamol and cadmium. The interference study confirms that the presence of other metal ions didn't inhibit the detection of cadmium by L-cys-Ag NPs. The limit of detection of paracetamol and cadmium by L-cys-Ag NPs was calculated to be 1.2 and 2.82 nM respectively. In addition, the real sample detection of paracetamol on blood serum and urine, and cadmium on STP were performed and the recovery percentage was above 97%. Further, the real sample analysis was performed in tap and drinking water and the recovery percentage was more than 98%. The analytic logic gate on the multicolour detection of cadmium and paracetamol was performed for the semi-quantitative monitoring of paracetamol and cadmium by L-cys-Ag NPs. The developed L-cys-Ag NPs were found to be an effective tool for the monitoring of cadmium in environmental water bodies and paracetamol in blood and urine.