Nano

Multi-walled carbon nanotube (MWCNT)-modified MoS₂/BiVO₄ was manufactured and used for the photoelectrochemical (PEC) detection of hydrogen peroxide (H₂O₂) and hypochlorite (ClO⁻). A solvothermal method was used to synthesize an MWCNT/MoS₂/BiVO₄ composite that showed perfect PEC properties because the MWCNTs and MoS₂/BiVO₄ heterostructures increased the composite’s stability against photocorrosion. Compared with the same signal of MWCNT/MoS₂/BiVO₄, the photocurrent signal of other composites was much smaller upon irradiation by visible light. According to this PEC sensor, the linear range of the H₂O₂ concentration was 1–200$\mu$M and 280–1560$\mu$M at $\mathrm{\text{pH}}=7.4$ based on the same pH when detecting ClO⁻ concentrations between 0.5–10$\mu$M and 20–340$\mu$M in a bleach sample. As a result, this sensor can be used to detect reactive oxygen species (ROS) in practical samples.

Collecting water from the fog becomes a promising strategy to address the water shortage. In this work, the CoO nanoneedle hierarchical structure was designed and prepared on the surface of the copper mesh by hydrothermal synthesis. The number of nanoclusters on the CoO nanoneedle array was changed by adjusting the mass concentration of the precursor solution. CoO nanoneedle array and nanoclusters form a hierarchical structure, which is conducive to the binding of air and the aggregation of water droplets. The results show that the surface of CoO nanoneedle hierarchical structure with good orientation and moderate sparsity has weak adhesion and stronger air binding capacity. Compared with other CoO nanoneedle structures, the hierarchical structure can effectively maintain the Cassie state wetting model for a long time, which improves the fog harvesting efficiency. This research offers a new strategy to design nanostructures for efficient fog collection, which has important implications on water harvesting from the air.

Multi-walled carbon nanotubes (MWCNTs) were grown on Silicon (Si) substrate by using low-pressure chemical vapor deposition (LPCVD) technique where iron (Fe) and silver (Ag) colloidal solution act as a catalyst were prepared by chemical route. The as-prepared solutions in varied concentrations were deposited on a Si substrate using a spin coating process at 700rpm. The purpose of Fe in composite catalysts is to have high carbon solubility and diffusion rate, and Ag utilization can change catalyst activity temperature and enhance carbon yields. In this work, we demonstrate the growth of carbon nanotubes (CNTs) on different catalyst concentrations (${}_{0.025\text{M}}$Fe/${}_{0.100\text{M}}$Ag), (${}_{0.050\text{M}}$Fe/${}_{0.100\text{M}}$Ag), (${}_{0.075\text{M}}$Fe/${}_{0.100\text{M}}$Ag) and (${}_{0.100\text{M}}$Fe/${}_{0.100\text{M}}$Ag) catalytic films. Field Emission Scanning Electron Microscopy (FESEM) was used to image the morphologies of various catalyst concentrations MWCNTs. The natures of the synthesized CNTs were determined using Raman spectroscopy and it was revealed that as-prepared CNTs are MWCNTs due to the absence of radial breathing mode (RBM). Raman spectroscopy demonstrated the lower I_D/I_G ratio (Ratio of the intensity of D-Raman peak and G-Raman peak) of (${}_{0.025\text{M}}$Fe/${}_{0.100\text{M}}$Ag) MWCNTs. The I_D/I_G ratio for (${}_{0.025\text{M}}$Fe/${}_{0.100\text{M}}$Ag) catalyzed MWCNTs was 0.76, while the I_D/I_G ratio for (${}_{0.100\text{M}}$Fe/${}_{0.100\text{M}}$Ag) catalyzed MWCNTs was 0.89. The (${}_{0.100\text{M}}$Fe/${}_{0.100\text{M}}$Ag) catalyzed MWCNTs were found to be more defective as compared to other. Electron Emission from (${}_{0.025\text{M}}$Fe/${}_{0.100\text{M}}$Ag) catalyzed MWCNTs were much stronger than from other samples, as demonstrated by Field Emission measurement using diode configuration. The turn-on field for (${}_{0.025\text{M}}$Fe/${}_{0.100\text{M}}$Ag) catalyzed MWCNTs was (0.92 V/$\mu$m) which is slightly lower than that of (${}_{0.100\text{M}}$Fe/${}_{0.100\text{M}}$Ag) catalyzed MWCNTs (1.83 V/$\mu$m), indicating superior enhancement.

Aim: In the present study, we sought to enhance the efficacy of radiotherapy via increasing the cellular uptake of Fe₃O₄@AuNPs as radiosensitizing agents using reversible electroporation, attaining a higher sensitivity for cancer cells to therapy-induced damage. Methods: The KB human nasopharyngeal carcinoma cell line was treated with different concentrations of gold-coated magnetic nanoparticles. The cells then received electroporation (750V/cm, 8 pulses for a duration 100$\mu$s with 100ms intervals) and radiotherapy (6MV X-ray, 2Gy). Control groups were carefully considered to assess the pure effect of both single and combinational therapeutic protocols. The MTT test and flow cytometry assay using Annexin V-PI kit were performed to evaluate potential effects on cell survival rate and to determine the induced level of apoptosis. Additionally, cellular uptake of nanoparticles was assessed and quantified using ICP-OES analysis. Results: Our study showed that nanoparticles and the applied procedure of electroporation had no considerable effects when utilized separately, but their combined application induced significant cell death ($>$45%) and apoptosis ($>$17%). Besides, the application of Fe₃O₄@AuNPs in the presence of electric field, 24h before the radiotherapy of tumor cells enhanced the cancer cell death ($>$53%) as well as apoptosis rate ($>$33%). The same scenario was also observed with normal HGF human gingival fibroblasts, confirmed by significantly lower levels of cell death and apoptosis. Conclusion: It can be concluded that electric fields at low voltage levels may significantly and selectively enhance the entry of nanoparticles into cancer cells, thereby accentuating the sensitivity of these cells to nanoparticle-mediated radiation therapy.

Neuroblastoma (NB) is one of the most common extracranial malignancies in children, accounting for 7–8% of childhood malignancies. As one of the main treatments for NB, radiotherapy is limited by various factors in clinics, such as the hypoxia microenvironment in tumor and serious side effects. Herein, we synthesized a kind of nanoscale coordination polymer denoted as Hf@DAP nanoparticles composed of hafnium ion (Hf${}^{4+})$ and 2,6-diaminopimelic acid (DAP), one of bacterial derivatives. From the image of transmission electron microscope (TEM), nanoparticles had uniform dispersion. Furthermore, the hydrodynamic diameter measured by dynamic light scattering method was about 190 nm. In this structure, the Hf${}^{4+}$ can enhance radiotherapy by effectively enhancing the function of X-ray, and the DAP was a biocompatible ligand for fabricating the nanoscale coordination nanoparticles. Furthermore, Hf@DAP nanoparticles were stable in various mediums and exhibited favorable biocompatibility in various cell lines in vitro. Cell viabilities were tested by cell counting kit (CCK-8) in vitro. There was no obvious cytotoxicity to normal cells, including NIH3T3, RAW264.7, and HUVECs, after incubation with Hf@DAP nanoparticles, indicating biocompatibilities of Hf@DAP nanoparticles. Additionally, a significantly enhanced radiotherapy effect was observed in the N2a cells, a kind of NB cell line, pretreated with Hf@DAP nanoparticles in vitro. The in vivo tumor growth was obviously inhibited in the mice with the combined therapy of Hf@DAP nanoparticles and X-ray, compared with PBS group, Hf@DAP group, and X-ray group. Furthermore, the survival time of the mice in the combined group was significantly prolonged, compared with PBS group. In addition, tissues structures of main organs, such as the lung, liver, spleen, and kidney in these mice, were ordered without the influence of Hf@DAP nanoparticles. Thus, this work proposed a potential radio-sensitizer for further clinical radiotherapy with limited side effects and high efficiency.

Membrane separation technology is attracting a broad spectrum of attention because of its low energy consumption and superior availability in oily wastewater treatment. Poly(vinylidene fluoride) (PVDF) membranes play an important role in membrane separation field. Herein, a kind of superhydrophilic/underwater superoleophobic nanoparticles modified PVDF membrane based on mussel-inspired chemistry was prepared via a one-pot method. This method applied the Michael addition/Schiff base reactions between dopamine (DA) and alkoxy hydrolysis of (3-Aminopropyl) trimethoxysilane (APTMS). The water contact angle (WCA) decreased from 117^∘ to 12.6^∘ after the modification. The resultant superhydrophilic/underwater superoleophobic membrane exhibited the outstanding water flux (12280.4L m${}^{-2}$ h${}^{-1}$ bar${}^{-1})$, which was a sixfold increment compared to Pristine PVDF. Besides, the resultant membranes showed the effective separation of various oil–water emulsions $(>98\%)$, and a high recoverability in multiple-iterations presented the membrane possessing the performance of persistent separation. With the simplicity of one-pot method preparation, outstanding performance, and environmental friendliness, this work provided a potential strategy to large-scale modified membrane materials for the treatment of oily wastewater.

Nano-porous Ta₂O₅ thin film electrodes are prepared by magnetron sputtering at low pressure in the presence of an oxygen atmosphere with an inert gas. The sputtered Ta₂O₅ thin film is subsequently annealed at 350^∘C for 2h in high pure N₂ (Ta₂O₅-350) to introduce oxygen deficiency. The Ta₂O₅-350 electrode possesses highly reversible lithium ion storage and good rate capability, which has high specific capacities of about 480mAh g${}^{-1}$ at a rate of 0.1C. Furthermore, after 2000 cycles at a rate of 5C the Ta₂O₅-350 electrode shows no obvious capacity decay and retains specific capacity of about 160mAhg${}^{-1}$. The excellent lithium storage properties of Ta₂O₅-350 electrode can be correlated to the nano-porous electrode architecture and oxygen deficiency.

In situ nanocomposites of graphene (Gr) and tungsten oxide hydrate (WO${}_3\cdot {\mathrm{\text{H}}}_2$O) nanoplates were synthesized via facile and energy-saving acid precipitation method at room temperature. The effect of the in situ composition on the physicochemical properties of WO${}_3\cdot {\mathrm{\text{H}}}_2$O platform material in nanocomposites was examined with X-ray diffraction, Raman scattering, UV–Vis reflectance spectra. Gr helped reduce microstrain, reduce the average crystalline size, increase the distance between (111) planes in WO${}_3\cdot {\mathrm{\text{H}}}_2$O platform nanoplates, and abnormally increase the optical bandgap. All samples showed a moderate photocatalytic activity in methylene blue (MB) removing efficiency under visible light irradiation, which was remarkably enhanced by adding 0.1mL H₂O₂. In comparison with both pristine and nanocomposite samples, the sample having 0.1wt.% of Gr in nanocomposite showed the highest MB removing efficiency of 47% and 99% in corresponding to without and with 0.1mL H₂O₂. The photocatalytic activity was assigned to the key role of the photogenerated holes, which was enhanced by compositing with Gr and/or the appearance of H₂O₂. The results of this work were a contribution to studying the photocatalytic mechanism of tungsten oxide hydrate-based nanocomposite and also proposed a facile method for preparing WO${}_3\cdot {\mathrm{\text{H}}}_2$O-based nanocomposite.