The discharge of liquid petroleum hydrocarbons into the environment is coined as an oil spill and is identified as a major form of ‘ocean pollution’. There are seven major proposed techniques to selectively remove spilled oil from water surfaces, and the choice of technique depends on the type of crude oil, temperature of the water, and other environmental conditions. After the proposal by Nicolaides et al. that the magnetic nanocomposite-based oil recovery method can be 30% less costly than other available methods, high surface area magnetic materials have received tremendous attention. Many interesting laboratory scale approaches have been reported so far on magnetic nanomaterial-based oil recovery. Most of the techniques use synergistic activities of engineered superhydrophobic scaffolds which are functionalized with magnetic particles either inherently or by external means. In this review article, the advancements in magnetic material-based oil spill clean-up are discussed by reviewing the literature from the last ten years. This review ends with the plausible future direction of this field and also discusses the commercial viability of some of these techniques.

COVID-19 belongs to a typical class of viruses that predominantly affects the human respiratory system, thereby proving to be fatal to many. The virus, along with other air pollutant particulates poses a severe threat to the human respiratory organs. Since the most common transmission mode is respiratory fomites and aerosol particulates, it is necessary to prevent their ingression through a mask. The primary use of masks is to prevent aerial particulates. This paper reveals the development of masks with air filters coated with functionalized graphene (fG) mounted on a 3D-printed facial mask replica. The fused deposition modeling (FDM) process is used for fabricating the facial mask replica. fG associated with nanosheets has an additional adsorbing capacity with a high surface area to volume ratio. fG coat is used over a polypropylene (PP) cloth through a dip coating method to enhance the antiviral and antimicrobial properties. The quality of fG was investigated through Raman spectroscopy and other characterization techniques such as SEM, XRD, and FTIR, which were used for visual interpretation of distributions of fG on a polypropylene (PP) fabric. Fabricated fG coated MB filters show 98.2% of bacterial filtration efficiency with 1.10 mbar of breathing resistance. The efficacy of the fG coated filter was tested against SARS-CoV-2 viral particles, which showed a complete arrest of viral transmission at the fG coated layer.

The discharge products of charge–discharge reactions of Na–O₂ cells are extensively studied by various physicochemical techniques and verified experimentally.