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Mesoporous silica (MPS) and MPS-Fe composite was prepared via sol–gel technique and characterized by BET, FTIR, XRD, SEM and pZc. The MPS and MPS-Fe adsorption efficiencies were evaluated for a cationic dye Turquoise-blue X-GB. The MPS-Fe composite showed pore size and BET values of 9.52 nm and 309 m2/g, respectively. XRD and SEM analysis revealed the amorphous nature and uniform distribution of spherical partciles with average particle size of 50 nm of MPS-Fe composite. The points of zero (pZc) charge found to be 2.3 and 6.3 for MPS and MPS-Fe, respectively. The MPS and MPS-Fe showed promising efficiency for the adsorption of Turquoise-blue X-GB as a function of medium pH, contact time, dye initial concentration and temperature. Among, Freundlich, Langmuir, Harkins–Jura, Temkin, Doubinin–Radushkevich isotherms, the Turquoise-blue X-GB followed Langmuir isothermal model with adsorption capacities of 83.34 mg/g and 74.07 mg/g for MPS and MPS-Fe composite, respectively. Among kinetics models, pseudo second order kinetic model fitted to the dye adsorption with R2 values of 0.998 and 0.988 for MPS and MPS-Fe composite, respectively. The negative values of enthalpy (ΔH) and free energy (ΔG) revealed exothermic and spontaneous adsorption of dye at room temperature. Results revealed that MPS and MPS-Fe composite have promising potential for Turquoise-blue X-GB dye adsorption and could possibly be extended for the adsorption of dyes from textile effluents.

A simple approach to deposit metal chalcogenide-based quantum-dots on TiO2 (anatase) nanoparticles via pseudo-successive ionic layer adsorption and reaction (p-SILAR) was opted to design and investigate the corresponding photoactivity under visible light. We used TiO2/PbS and TiO2/CdS nanocomposites for photocatalysis after which we prepared solar paints from them to put side by side the resultant photovoltaic performance. We developed solar paint type quantum-dot-sensitized solar cells (QDSCs) from TiO2/PbS and TiO2/CdS nanocomposites to divulge electron-hole generation, electron-hole recombination, and resistance against photo-corrosion. TiO2/PbS exhibited higher electron-hole generation than TiO2/CdS owing to its efficient visible light harvesting capability which resulted in higher photocurrent density (JSC) and thus higher power conversion efficiency (PCE) for respective QDSC; however, it had inferior resistance against photo-corrosion. Additionally, the degradation of an azo-based dye (acid orange-56) reflected an effectual increase in the photocatalytic activity of anatase-TiO2 as a result of deposition of PbS and CdS QDs. TiO2/PbS performed better than TiO2/CdS as a photocatalyst under visible light irradiation.

In view of low cost and efficient adsorbents exploration, present study was aimed to evaluate the possibility of Pitpapra waste biomass (roots, leaves, stem) for adsorption of Zn (II) and Co (II) metals in single metal system (SMS) and binary metal system (BMS). The process variables were optimized for the maximum adsorption of metal ions. Pitpapra stem, leaves and root biomasses showed promising efficiency for the adsorption of Co (II) and Zn (II) ions and at optimized conditions of process variable, 225 mg/g and 230 mg/g of Co (II) and Zn (II) ions were removed from aqueous media, respectively. The behavior of Zn (II) in BMS changed, however, Co (II) did not show any change in BMS versus SMS. Freundlich isotherm fitted well to the adsorption data of Co (II) and Zn (II). In view of efficient adsorption of Co (II) and Zn (II) ions, the use of Pitpapra biomass is suggested for the adsorption of heavy metals from wastewater.

Owing to its excellent thermal and mechanical properties of graphene, graphene-based composites have attracted tremendous research interest in recent years. In particular, graphene with high thermal conductivity becomes an important and promising filler in composites for thermal management. This critical review focus on the recent advances in graphene-based composites with high thermal conductivity. After the introduction of thermal conductive mechanisms of graphene-based composites, the fabrication methods of graphene-based composites are summarized. Then we also discuss currently researches of various graphene-based composites such as graphene/thermoplastic composites and graphene/thermoset composites. Herein, the mechanisms, preparation, and properties of graphene-based composites are discussed along with detailed examples from the scientific literature and the guidance are provided on the fabrication of composites with high thermal conductivity.

A novel diamine 4-(4-aminophenoxy)butyl-4-aminophenyl ether (ABAE) was synthesized as a chain extender (CE) by a quick and facile method using microwave reactor. CE was used for the preparation of stimuli-responsive Polyurethane-urea elastomer (PUU) with the ratio of NCO/OH from 2 to 2.5. Synthesized PUU was characterized with the help of Fourier transform infrared spectroscopy (FTIR), derivative thermogravimetric analysis (DTG), and scanning electron microscopy SEM. PUU films were loaded with an anti-cancer drug “doxorubicin”. Drug release kinetics were studied in different solvents, at different pH values and with different NCO contents of PUU. The maximum of 45% cumulative drug release was observed in DMSO while the drug release increased with the decrease in pH and a maximum cumulative release of 47% was observed at acidic pH of 4.4. The minimum drug was released from the one, which was crosslinked with highest ratio (2.5) of NCO/OH. So, we can say that drug release can easily be adjusted under different conditions and environments with the help of these stimuli-responsive media.

Correction for ‘Magnetic mesoporous bioactive glass for synergetic use in bone regeneration, hyperthermia treatment, and controlled drug delivery’ by Muhammad Saif Ur Rahman et al., RSC Adv., 2020, 10, 21413–21419, DOI: 10.1039/C9RA09349D.

Dual functional, magnesium-doped mesoporous bioactive glass nanoparticles (Mg-MBG NPs) were prepared for bone regeneration and drug delivery. Template-assisted (F127) economical sol-gel method was used to prepare spherical Mg-MBG NPS of 65 ± 5 nm as determined by TEM. Different initial concentrations (0.1–0.5 mg/mL) of Mitomycin C (Mc) were used for loading to the Mg-MBG, and as a result, the variable amount of drug was loaded. Drug release was studied at different pH values (6.4, 7.4 & 8.4) of the release media which showed a maximum cumulative release of 89%, at a pH of 6.4. MTT assay indicated no significant cytotoxicity in normal human fibroblast (NHFB) cells and in vivo tissue histopathology revealed no damage to the cells. Mc loaded Mg-MBG NPs inhibited the MG-63 cancer cell viability at all concentrations and showed the IC50 value of 20.8 µg/mL. XRD and FTIR spectra confirmed the formation of hydroxycarbonate apatite (HCA) upon immersion in simulated body fluid (SBF). Thus biocompatible Mg-MBG with low cytotoxicity and sustained drug release was entitled as a safe biomaterial.