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Metallic nanostructures play a vital role in the nanoscale engineering of flexible optoelectronic devices as active units. Due to the limited flexibility properties of nanoparticles, researchers are devoting much more attention nowadays to nanowires (NWs) for designing flexible transparent electrodes for different electronic devices. Silver NW (AgNW) possesses a 1D structure with a changeable aspect ratio. It also includes up-to-date properties for future optoelectronic devices, such as low cost, high conductivity, high transparency, and mechanical flexibility. In view of the increasing demand for AgNWs, commercial-scale synthesis of AgNWs is inevitable. However, high discrepancies among the published data have resulted in a major delay in its commercialization. Therefore, this review critically discusses the ignored factors that limit AgNW commercialization and provide possible solutions.

Nanoparticles (NPs) are extensively being used in state-of-the-art nano-based therapies, modern electronics, and consumer products, so can be released into the environment with enhancement interaction with humans. Hence, the exposures to these multifunctional NPs lead to changes in protein structure and functionality, raising serious health issues. This study thoroughly investigated the interaction and adsorption of catalase (CAT) with HfO2-NPs by circular dichroism (CD), Fourier transform infrared (FTIR), absorption, and fluorescence spectroscopic techniques. The results indicate that HfO2 NPs cause fluorescence quenching in CAT by a static quenching mechanism. The negative values of Vant Hoff thermodynamic expressions (ΔH o , ΔS o , and ΔG o ) corroborate the spontaneity and exothermic nature of static quenching driven by van der Waals forces and hydrogen bonding. Also, FTIR, UV-CD, and UV–visible spectroscopy techniques confirmed that HfO2 NPs binding could induce microenvironment perturbations leading to secondary and tertiary conformation changes in CAT. Furthermore, synchronous fluorescence spectroscopy confirmed the significant changes in the microenvironment around tryptophan (Trp) residue caused by HfO2 NPs. The time depending denaturing of CAT biochemistry through HfO2-NPs was investigated by assaying catalase activity elucidates the potential toxic action of HfO2-NPs at the macromolecular level. Briefly, this provides an empathetic knowledge of the nanotoxicity and likely health effects of HfO2 NPs exposure.

A novel graphene nanoplatelets (GNP) bridge between two semiconductors (AgBr and graphitic carbon nitride) was created to boost photoelectrochemical performance. The heterojunction created makes the whole system a Z-scheme catalyst. For the construction of this catalyst, the syringe pump methodology was adopted and different analytical techniques were used for the confirmation of structure and morphology. High angle annular dark field (HAADF), dark field (DF), DF-4 and DF-2 techniques, using Z-contrast phenomena, confirmed the heterostructure (ABGCN) and its composition. The constructed structure showed an enhanced photoelectrochemical and catalytic property against ‘acute toxicity category-III (MM)’ and ‘category-IV (tetracycline hydrochloride (TH))’ organic pollutants. The constructed catalyst degraded the MM in 57 min and the TH in 35 min with degradation rates of 0.01489 min−1 and 0.02387 min−1, respectively, due to the accumulation of photogenerated electrons on the conduction band (CB) of g-C3N4 and photogenerated holes on the valence band (VB) of AgBr by the transformation of charges through the graphene bridge. An ion trapping study also revealed that ·O2 and h+ were the active species which actively participated in the photocatalytic reaction.

Superfine paramagnetic nickel particles were synthesized by using different anionic and cation surfactants in the presence of propylene glycol. Surfactants including gum arabic, gelatin, PVP and tri-sodium citrate were used. SEM analysis proved that the morphology of nickel particles was perfectly spherical with little agglomeration. The morphology of microspheres was changed with variation of anionic and cationic surfactants, but majorly the spherical shape of nickel particles was retained. The purity of superfine nickel particles was also confirmed with EDS results which confirmed the presence of superfine nickel particles. The XRD analysis results also indicated the presence of "fcc" crystal in the superfine particles. The magnetic field analysis designated the existence of magnetic properties in synthesized superfine nickel particles. Surface area properties were also measured with the help of BET analysis which determined the enhanced catalytic property of these particles. Overall the synthesized nickel superfine microspheres possesses improved morphology and magnetic properties with the addition of PVP as surfactant as compared to gum arabic, gelatin, and tri-sodium citrate.

The flower like microrods (MR) of α-Bi2O3 defined as (MR-Bi2O3) and ultrathin g-C3N4(UT-C3N4) p-n junction was successfully prepared by loading different concentrations of UT-C3N4 over MR-Bi2O3. Their morphology and structure were thoroughly studied by XRD, SEM, XPS, TEM, UV–vis diffuse reflectance spectra, FT-IR and PL spectra. The results showed that the UT-C3N4 has been wrapped in the flower like MR-Bi2O3. The designing of the p-n junction of UT- C3N4 and MR-Bi2O3 can enhance the separation efficiency of the electron-hole pairs. The photocatalytic degradation of RhB was drastically increased by designing of the p-n junction that is due to the photogenerated electron–hole pair's separation efficiency.

Exfoliation of porous g-C3N4 has been proved a very effective way to prepare g-C3N4 nanosheets (2D layered materials). Here, we present an environment-friendly, high-efficiency and easy scale-up preparation method of curly leaf-like g-C3N4 nanosheets (CL-CN) by liquid-phase exfoliation of honeycomb-like porous g-C3N4 (HP-CN). Two-dimensional curly nanosheets have induced excellent physicochemical properties, i.e. large surface area, high fluorescence quantum efficiency, wide band gap and good water-dispersibility. The photocatalytic performance of CL-CN in degradation of RhB under visible light is much better than that of honeycomb-like porous g-C3N4 and bulk g-C3N4. The improved photocatalytic performance of CL-CN is well explained by the improved physicochemical properties and photocatalytic mechanism. In addition, CL-CN being a 2D layered material with excellent photoluminescence characteristic and non-toxic behavior can be widely applied in bio-medicine, bio-imaging and biosensors field.