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Optical glasses possessing large third-order optical nonlinear susceptibility and fast response times are promising materials for the development of advanced nonlinear photonic devices. In this context, gold nanoparticle (NP)-doped borate glasses were synthesized via the melt-quench method. The nonlinear optical (NLO) properties of thus prepared glasses were investigated at different wavelengths (i.e., at 532 nm using nanosecond pulses, at 750 nm, 800 nm, and 850 nm wavelengths using femtosecond, MHz pulses). At 532 nm, open aperture (OA) Z-scan signatures of gold NP-doped borate glasses demonstrated reverse saturable absorption (RSA), attributed to mixed intra-band and interband transitions, while in the 750-850 nm region, the OA Z-scan data revealed the presence of saturable absorption (SA), possibly due to intra-band transitions. The NLO coefficients were evaluated at all the spectral regions and further compared with some of the recently reported glasses. The magnitudes of obtained NLO coefficients clearly demonstrate that the investigated glasses are potential materials for photonic device applications.

Summary Reduced graphene oxide (RGO) based composite non‐selective solar absorber coatings (RGO/silicate) were developed using a simple spray technique. RGO powders were prepared using the modified Hummers' method. RGO‐silicate suspensions were obtained by adding an appropriate quantity of RGO in a sodium silicate solution. Transmission electron microscopy studies showed the corrugated morphology of reduced graphene oxide powders. The presence of RGO in the composite absorber coatings was confirmed by X‐ray photoelectron spectroscopy data. In order to study the thermal stability, the coatings were deposited on stainless steel (SS) and Inconel substrates. The composite nonselective coating exhibited an absorptance (α) of 0.96 and emittance (ε) of 0.88 at 82°C on SS and Inconel substrates. The coatings sprayed on SS substrates showed good thermal stability for 428 hours at 500°C in air. The coatings sprayed on Inconel substrates were thermally stable in air at 600°C for 96 hours. The performance evaluation tests revealed that these coatings can be used for concentrated solar power applications.

The management of infectious diseases is one of the major public health challenges of the 21st century. Mutation of the microbes, biofilm formation, and other structural-morphological behaviors have resulted in pathogens acquiring multi-drug resistance. The development of advanced materials that can provide long-lasting and effective protection against harmful microbes is becoming a need of the hour. Biocompatibility, efficient microbial inactivation, thermal and chemical stability of nanomaterials help to reduce the excessive use of antibiotics and, thus, to overcome antimicrobial resistance. Metal and metal oxide nanostructures, graphene, carbon dots, and other two-dimensional materials exhibit excellent antimicrobial properties. This review provides a comprehensive overview of antibacterial mechanisms and factors that help to inactivate the bacteria by nanomaterials. It also points out the enhanced antibacterial behaviors of the modified nanomaterials for future research concerns.

Graphene, a layered allotropic form of graphitic carbon, has fascinated the scientific world from the time of its discovery. Its unique structural, physical, chemical, mechanical, and electrical properties find application in many areas. Because of its large surface area as well as its apt electrical property, it is used in electromagnetic interference shielding. With excellent carrier mobility, it is used for sensing purposes. Mechanical strength and elastic properties coupled with its lightweight makes graphene a promising material as a supercapacitor. The 2-dimensional structural properties of the graphene layers can be used for the purification treatment of water and gas. The number of researches in graphene applications are increasing every single day which shows the importance and excellency of graphene properties. This short review provides a comprehensive understanding of the properties and progress of graphene in the field of electromagnetic interference shielding, sensors, water treatment, energy production, storage, and conversion applications such as supercapacitors, fuel cells, solar cells and electrocatalysts.