Enhanced Sunlight-Powered Photocatalysis and Methanol Oxidation Activities of Co3O4-Embedded Polymeric Carbon Nitride Nanostructures.

The contamination of water by organic substances poses a significant global challenge. To address these pressing environmental and energy concerns, this study emphasizes the importance of developing effective photocatalysts powered by sunlight. In this research, we achieved the successful synthesis of a novel photocatalyst comprised of polymeric carbon nitride (CN) nanosheets embedded with Co3O4 material, denoted as CN-CO. The synthesis process involved subjecting the mixture to 500 °C for 10 h in a muffle furnace. Structural and morphological analyses confirmed the formation of CN-CO nanostructures, which exhibited remarkable enhancements in photocatalytic activity for the removal of methylene blue (MB) pollutants under replicated sunlight. After 90 min of exposure, the degradation rate reached an impressive 98.9%, surpassing the degradation rates of 62.3% for pure CN and 89.32% for pure Co3O4 during the same time period. This significant improvement can be attributed to the exceptional light captivation capabilities and efficient charge separation abilities of the CN-CO nanostructures. Furthermore, the CN-CO nanostructures demonstrated impressive photocurrent density-time (j-t) activity under sunlight, with a photocurrent density of 2.51 µA/cm2 at 0.5 V. The CN-CO nanostructure exhibited excellent methanol oxidation reaction (MOR) activity with the highest current density of 83.71 mA/cm2 at an optimal 2 M methanol concentration, benefiting from the synergy effects of CN and CO in the nanostructure. Overall, this study presents a straightforward and effective method for producing CN-based photocatalysts decorated with semiconductor nanosized materials. The outcomes of this research shed light on the design of nanostructures for energy-related applications, while also providing insights into the development of efficient photocatalytic materials for addressing environmental challenges.

In-vitro evaluation of copper nanoparticles cytotoxicity on prostate cancer cell lines and their antioxidant, sensing and catalytic activity: One-pot green approach.

In this study, Broccoli green extract was reported as a green and environmental friendly precursor for the one-pot biosynthesis of copper nanoparticles. The synthesized nanoparticles were characterized by UV-vis, FTIR, TEM, DLS, XRD and cyclic voltammetry. The TEM and DLS results showed that the NPs are in spherical and monodispersed with an average particle size of ~4.8nm. The FTIR results confirmed the occurrence of bioactive functional groups that are responsible for reducing cupric sulphate to copper ions. The UV-vis spectrophotometry was used for catalytic reduction of 4-nitrophenol and its dynamic reaction in Britton-Robinson buffer solution. This catalytic activity was further supported with methylene blue and methyl red dyes degradation. The nanocatalyst can be recovered from the reaction mixture and reused many times with none vital loss of catalytic activity. The Broccoli green extract modified copper nanoparticles coated on screen printing electrode laid a new sensing platform and has an excellent electrocatalytic activity. Furthermore, surface modified CuNPs with Broccoli green extract exhibited no cytotoxicity at the concentration ranging from 0.5 to 1.5µM on the prostate cancer (PC-3) cell lines. The maximum scavenging % of Broccoli green extract modified CuNPs was found to be >70.50% at the concentration of 0.25mM against 1,1-diphenyl-2-picrylhydrazyl.

Differential pulse adsorptive stripping voltammetric determination of simeton in its formulations and vegetables.

A sensitive adsorptive stripping voltammetric method for the determination of simeton with universal buffer solution has been described. The method was based on the adsorption accumulation of simeton at a hanging mercury drop electrode. The overall reduction process is under controlled diffusion. The adsorptive peak was observed at -0.8 V vs SCE in acidic solution 2

Solid phase extraction method for the determination of lead, nickel, copper and manganese by flame atomic absorption spectrometry using sodium bispiperdine-1,1'-carbotetrathioate (Na-BPCTT) in water samples.

A novel column solid phase extraction procedure was developed for the determination of lead, nickel, copper and manganese in various water samples by flame atomic absorption spectrometry (FAAS) after preconcentration on sodium bispiperdine-1,1'-carbotetrathioate (Na-BPCTT) supported by Amberlite XAD-7. The sorbed element was subsequently eluted with 1M nitric acid and the acid eluates are analysed by Flame atomic absorption spectrometry (FAAS). Various parameters such as pH, amount of adsorbent, eluent type and volume, flow-rate of the sample solution, volume of the sample solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH for the sorption of above mentioned metal ions was about 6.0+/-0.2. The loading capacity of adsorbent for Pb, Cu, Ni and Mn were found to 28, 26, 22 and 20x10(-6) g/mL, respectively. The recoveries of lead, copper, nickel and manganese under optimum conditions were found to be 96.7-99.2 at the 95% confident level. The limit of detection was 3.0, 3.2, 2.8 and 3.6x10(-6) g/mL for lead, copper, nickel and manganese, respectively by applying a preconcentration factor 50. The proposed enrichment method was applied for metal ions in various water samples. The results were obtained are good agreement with reported method.

Novel analytical reagent for the application of cloud-point preconcentration and flame atomic absorption spectrometric determination of nickel in natural water samples.

Cloud-point extraction was applied as a preconcentration of nickel after formation of complex with newly synthesized N-quino[8,7-b]azin-5-yl-2,3,5,6,8,9,11,12octahydrobenzo[b][1,4,7,10,13]pentaoxacyclopentadecin-15-yl-methanimine, and later determined by flame atomic absorption spectrometry (FAAS) using octyl phenoxy polyethoxy ethanol (Triton X-114) as surfactant. Nickel was complexed with N-quino[8,7-b]azin-5-yl-2,3,5,6,8,9,11,12octahydrobenzo[b][1,4,7,10,13]pentaoxacyclopentadecin-15-yl-methanimine in an aqueous phase and was kept for 15 min in a thermo-stated bath at 40 degrees C. Separation of the two phases was accomplished by centrifugation for 15 min at 4000 rpm. The chemical variables affecting the cloud-point extraction were evaluated, optimized and successfully applied to the nickel determination in various water samples. Under the optimized conditions, the preconcentration system of 100 ml sample permitted an enhancement factor of 50-fold. The detailed study of various interferences made the method more selective. The detection limits obtained under optimal condition was 0.042 ngml(-1). The extraction efficiency was investigated at different nickel concentrations (20-80 ngml(-1)) and good recoveries (99.05-99.93%) were obtained using present method. The proposed method has been applied successfully for the determination of nickel in various water samples and compared with reported method in terms of Student's t-test and variance ratio f-test which indicate the significance of present method over reported and spectrophotometric methods at 95% confidence level.