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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.

316 L Stainless steel is widely used industrial material having application in broad range of domain including automotive, structural as well as biomedical. It is also used for several high temperature applications in various industries, permanent deformation due to thermal cycling and continuous high temperature exposure is one of the major concern in industries. Therefore, enticing thermo physical properties is very crucial for better efficiency and service life of components. In the present work, graphene reinforced 316 L metal matrix composite was prepared via powder bed fusion additive manufacturing technique in order to make it more stable material at elevated temperature. Powder bed fusion technique was used to melt graphene coated 316 L metal powder layer by layer to prevent agglomeration of graphene inside the matrix. To identify the chemical state of the elements in the prepared composite, synchrotron based X-ray photoelectron spectroscopy was performed. However, no carbide formation was observed inside the matrix and the prepared composite was purely austenitic. The obtained composite with 0.2 wt % graphene has coefficient of thermal expansion (CTE) equal to 19.3 × 10−6 K-1 which is about 6.2% lower than bare 316 L at 1100 °C. The value further decrease after annealing process and this much decrement in CTE can increase the application window of the material to the large extent.