Phosphorous- and Boron-Doped Graphene-Based Nanomaterials for Energy-Related Applications.

Doping is a great strategy for tuning the characteristics of graphene-based nanomaterials. Phosphorous has a higher electronegativity as compared to carbon, whereas boron can induce p-type conductivity in graphene. This review provides insight into the different synthesis routes of phosphorous- and boron-doped graphene along with their applications in supercapacitors, lithium- ions batteries, and cells such as solar and fuel cells. The two major approaches for the synthesis, viz. direct and post-treatment methods, are discussed in detail. The former synthetic strategies include ball milling and chemical vapor discharge approaches, whereas self-assembly, thermal annealing, arc-discharge, wet chemical, and electrochemical erosion are representative post-treatment methods. The latter techniques keep the original graphene structure via more surface doping than substitutional doping. As a result, it is possible to preserve the features of the graphene while offering a straightforward handling technique that is more stable and controllable than direct techniques. This review also explains the latest progress in the prospective uses of graphene doped with phosphorous and boron for electronic devices, i.e., fuel and solar cells, supercapacitors, and batteries. Their novel energy-related applications will continue to be a promising area of study.

Comparative studies on adsorptive and photocatalytic potential of differently synthesized ferric oxide nanoparticles for malachite green.

In the present work, effect of different fuels on the structural, morphological, magnetic, adsorptive and photocatalytic properties of ferric oxide nanoparticles (Fe2O3 NPs) was evaluated. Fe2O3 NPs were synthesized via combustion method by using oxalyl dihydrazide (ODH), polyethylene glycol (PEG) and urea as fuels. The indigenously synthesized NPs were characterized by different analytical tools. XRD patterns confirmed the presence of α- and γ-Fe2O3 phases. TEM micrographs displayed average particle size was less than 30 nm. Saturation magnetization amplified with increase in the γ-Fe2O3 content, which was correlated to the fuel used for synthesis. Adsorptive and photocatalytic activity of synthesized NPs was studied using malachite green (MG) dye as a model compound. The uptake behavior for MG dye was influenced by the solution pH, contact time, adsorbent dose, temperature and dye concentration. Thermodynamic studies indicated the endothermic nature of the adsorption phenomenon. The adsorption was well defined with Langmuir and Freundlich isotherms in comparison to Dubinin-Radushkevitch adsorption isotherm model. The trend for percentage removal of MG dye using NPs synthesized by different fuels was: urea > PEG > ODH. Fe2O3 NPs facilitated photo degradation of dye solution in ultra-violet and visible light irradiations.