Nano

In this paper, Cu₂O/ZnO/GaN hierarchical nanoarchitectonics was synthesized using a solution process. The hierarchical nanoarchitectonics was assembled from in situ etching and growth Cu₂O nanostructures on random distributed ZnO nanotubes/GaN film by hydrothermal process. The device demonstrated multiple wavelength photodetection. It demonstrates that the detector based on Cu₂O/ZnO/GaN hierarchical nanoarchitectonics can be used as a low-cost multiple band detection areas.

Intercalation-doped multilayer graphene nanoribbon (ID-MLGNR) is a potential contender for future interconnect applications. This work presents a comprehensive analysis of temperature-dependent design issues in ID-MLGNR-based future VLSI interconnects based on a temperature-dependent mean free path (MFP) model incorporating scattering owning to rough edges and defects in GNRs, which consequently reflects the extrinsic temperature-dependent circuit behavior of these interconnects in terms of wire impedance, propagation delay, and power dissipation. It is found that in deep submicron (DSM) regime, at a specific technology node of 14-nm MFP, edge scattering improves by 74% as Fermi energy ($E_F)$ increases from 0.2 to 0.6, and at a specularity constant, $p=0.6$ for local and intermediate level of interconnects. For similar values of $E_F$ and $p$, at global length, this rise in MFP is about 70%, which signifies the significant reduction in resistance (varies inversely to MFP). Whereas, negligible variations are observed in the conductance and inductance of ID-MLGNR interconnects with an increase in temperature. Nevertheless, the reduction in resistance for local & intermediate, and global MLGNR interconnects reflects its low propagation delay and power-delay-product (PDP) for future VLSI ICs applications despite the negligibly poor decrease in power dissipation (with an overall % reduction in the power dissipation from 300K to 500K evaluated to 3.54% regardless increase in $E_F$ from 0.2eV to 0.6eV).

Nanosilver (AgNPs) exhibit a wide range of potential uses in the optical, antibacterial, and catalytic fields, and biologically produced AgNPs have a number of benefits. Our lab earlier identified the Lysinibacillus sphaericus protein NA33, which is involved in the synthesis of AgNPs. Nevertheless, NA33 produced AgNPs with poor dispersion, a high particle size, and low efficiency. In order to address these difficulties, we successfully produced SNA15, a highly effective AgNPs recombinant protein, was produced after molecular modification of NA33. SNA15 demonstrated good stability, with a yield of 87 mg SNA15 isolated from per liter of Escherichia coli fermentation broth. No apparent precipitation was observed after 7–5 days longer than the original protein—of storage in a 4${}^{\circ }$C refrigerator. The generated AgNPs by SNA15, had particle sizes ranging from 3nm to 20nm, which were smaller than the original synthesized AgNPs of 30–50nm by NA33 and demonstrated spectrum antibacterial activity. There will be many opportunities for application in the medical and healthcare industries.

Magnetic drug delivery is an effective method to decrease the side effects of traditional drug delivery methods. To enhance the efficiency of magnetic nanoparticle transport, a precise and cost-effective magnetic system is required. In this research, different arrangements of NdFeB magnets for drug delivery in human spinal cord were presented and then compared. Assummed magnetic nanoparticles are injected into the cerebrospinal fluid (CSF) and focused on the disease site with external magnets. The effects of these magnets on nanoparticles have been investigated. The results show that the arrangement of sharp magnets has a more accurate performance in delivering nanoparticles to the damage site than other arrangements. The designed magnetic system can improve the accuracy of drug delivery in the spinal cord compared to previous methods.

Gemini surfactants, composed of two surfactant monomers, are likely to self-assemble into viscoelastic fluids in water at low concentrations. Here, the aggregation behaviors of quaternary ammonium gemini surfactant with a hydroxyl group on the spacer (16-3OH-16) have been studied in the dilute aqueous system by rheological techniques, small angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and other characterizations. At room temperature, the samples behave as elastic gels. The structure and morphology of gels were confirmed by SAXS and SEM characterizations. Due to the hydroxyl group on the spacer of 16-3OH-16, the gels are more stable than those formed by 16-3-16. At high temperature, the gels transform into wormlike micelles and behave as viscoelastic fluids. The obtained results would help to construct complexed fluids with structure tailorable gemini surfactants.

Carbon dots (CDs), as an important carbon-based nanomaterial, have been widely used in fluorescence (FL) detection, bioimaging, photocatalysis, light-emitting devices (LEDs) and many other fields, owing to their excellent optical properties. Regulating the fluorescent properties of carbon dots (CDs) in a controlled manner has been a fundamental research goal. Herein, solvent-dependent CDs (N-CDs) are synthesized through the solvothermal reaction of $o$-phenylenediamine (OPD) in ethanol. When N-CDs are dispersed in solvents of different polarities, the emission wavelength only turned 39nm red-shift. While, the O-CDs are obtained by modifying the surface of N-CDs with 1,2,4-benzenetricarboxylic acid (TMA). O-CDs show four obvious FL emission peaks in the yellow, orange and red regions at 554nm, 604nm, 650nm and 712nm with a tail extending to 750nm, even entering into near-infrared-I (NIR-I) region. Thus, according to the special structure of CDs, this work provides a novel donor-$\pi$-acceptor (D-$\pi$-A) strategy for preparing long wavelength emissive CDs. Finally, the N-CDs and O-CDs are successfully applied to cellular imaging.

Transition metal selenides are considered as promising anode materials for sodium-ion batteries (SIBs) due to their high capacity and low cost. However, they suffer from large volume change, serious polyselenide dissolution and sluggish reaction kinetics during charge/discharge process, resulting in poor cycling stability and low rate performance for SIBs, which further restrict their widespread application. Here, we developed carbon-free three-dimensional (3D) hierarchical microflower-shaped CoSe₂ with a diameter size of approximately 2$\mu$m, composed of nanosheets through a one-step solvothermal method. The thin nanosheets are conducive to shortening the Na${}^{+}$ diffusion channels and relieving the volume expansion, and the 3D hierarchical microflower architecture could effectively prevent the agglomeration of nanosheets; accordingly, the resulting CoSe₂ microflowers deliver a high specific capacity of 451.94mAhg${}^{-1}$ even at 0.5Ag${}^{-1}$ after 100 cycles, compared with CoSe₂ nanoparticles. This work offers an approach for designing metal selenides with high capacities and rate capability for SIBs.

The main objective of this work is to study and optimize by simulation a proposed perovskite solar cell (PSC) model. The model is a two-layer perovskite solar cell in which the two perovskite materials CH₃NH₃PbI₃ (MAPI) and HC(NH${}_2{)}_2$PbI₃ (FAPI) form the active layer of the cell, according to the configuration Pt/CuSbS₂/CH₃NH₃PbI₃/HC(NH${}_2{)}_2$PbI₃/ZnO/FTO. The simulations were performed using SCAPS 1D software. The optimized parameters are mainly the thicknesses of the active sub-layers (MAPI and FAPI), and the parameters associated with these materials such as defect density and doping density. The defect densities of the CuSbS₂/MAPI, MAPI/FAPI, and MAPI/ZnO interfaces have also been optimized. The best results were obtained for an optimal thickness of 1200nm, an acceptor doping density of 10${}^{22}$cm${}^{-3}$, and a defect density of 10${}^{12}$cm${}^{-3}$ for each active sub-layer (MAPI and FAPI). For the defect densities of the three interfaces, the density 10${}^{12}$cm${}^{-2}$ was found as the optimal density. The optimized cell has an open circuit voltage of 1.519V, a short circuit current density of 27.79mA/cm², a fill factor of 91.31%, and a power conversion efficiency of 38.53%.

CdO/CdS nanocomposites have been synthesized via the solution combustion route. These nanocomposites have been characterized in terms of XRD, FESEM, EDS, UV-visible and FTIR spectroscopy. The crystallinity and the crystallite size of the as-synthesized CdO/CdS nanocomposites were calculated from XRD, whereas the surface morphology and chemical purity were obtained from FESEM and EDS analysis. Further, all the samples were used as photocatalyst for the degradation of methyl orange (MO) dye under UV-Visible irradiation. The rate constant, $k$, was obtained by the Langmuir–Hinshelwood model. From $k$ values, it can be observed that the rate constant increases on increasing the amount of photocatalyst due to an increase in surface area. The rate constant value for CdO/CdS nanocomposite annealed at 615${}^{\circ }$C was found to be very low, which may be largely due to loss in crystallinity at this higher temperature. Further, we compared our results with those reported in the literature and it was observed that CdO/CdS nanocomposites act as a better photocatalyst than others.