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1.
Polyacrylonitrile (PAN)/β-cyclodextrin (β-CD) composite nanofibrous membranes immobilized with nano-titanium dioxide (TiO2) and graphene oxide (GO) were prepared by electrospinning and ultrasonic-assisted electrospinning. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray diffraction (XRD) confirmed that TiO2 and GO were more evenly dispersed on the surface and inside of the nanofibers after 45 min of ultrasonic treatment. Adding TiO2 and GO reduced the fiber diameter; the minimum fiber diameter was 84.66 ± 40.58 nm when the mass ratio of TiO2-to-GO was 8:2 (PAN/β-CD nanofibrous membranes was 191.10 ± 45.66 nm). Using the anionic dye methyl orange (MO) and the cationic dye methylene blue (MB) as pollutant models, the photocatalytic activity of the nanofibrous membrane under natural sunlight was evaluated. It was found that PAN/β-CD/TiO2/GO composite nanofibrous membrane with an 8:2 mass ratio of TiO2-to-GO exhibited the best degradation efficiency for the dyes. The degradation efficiency for MB and MO were 93.52 ± 1.83% and 90.92 ± 1.52%, respectively. Meanwhile, the PAN/β-CD/TiO2/GO composite nanofibrous membrane also displayed good antibacterial properties and the degradation efficiency for MB and MO remained above 80% after 3 cycles. In general, the PAN/β-CD/TiO2/GO nanofibrous membrane is eco-friendly, reusable, and has great potential for the removal of dyes from industrial wastewaters.  相似文献   
2.
Perovskite solar cells have been studied extensively in the area of perovskite solar cells because they have a comparatively free hysteresis. Through fabrication of a perovskite solar cell based on a vanadium oxide buffer, this study clarified the mechanism of electron and hole transport in the laminated layer upon irradiation with light. The power conversion efficiency (PCE) of the Vanadium (Ⅳ) oxide (VO2) sputtering process device was approximately 13% and with the spin-coating process was 8.5%. To investigate the physicochemical origin of such PCE differences depending on the process type, comprehensive band alignment and band structure analyses of the actual cell stacks were performed using X-ray photoelectron spectroscopy depth measurements. Accordingly, it was found that the inconsistent valence band offset between the perovskite absorption layer and V2O5 layer as a function of the VO2 process type caused a difference in the hole transport, resulting in the difference in the efficiency.  相似文献   
3.
An amorphous cobalt boride alloy with high electronic conductivity is fabricated through the liquid-phase reduction method. Benefiting from large specific surface area and hierarchical pore structure, the as-synthesized Co-B nanoflakes expose substantial electrochemical active sites, promote the transfer of electrons and ions, and accelerate the redox kinetic process. The as-obtained amorphous Co-B alloy sample displays a specific capacitance of 411 F g−1 at 0.5 A g−1, and with the current density increased to 10 A g−1, it maintains 69% of the initial capacitance. The as-assembled asymmetric supercapacitor device reveals electrochemical properties comprising an excellent specific capacitance of 64.3 F g−1 at 0.25 A g−1, superior cyclical stability of 105% after 20,000 cycles at 3 A g−1, and maximum energy density of 22.9 Wh kg−1 at a power density of 200.3 W kg−1. This study demonstrates great potential in developing high-conductivity materials for an asymmetric supercapacitor through utilizing an amorphous cobalt boride alloy as a promising electrode material.  相似文献   
4.
The detection of cancer biomarkers is of great significance for the early screening of cancer. Detecting the content of sarcosine in blood or urine has been considered to provide a basis for the diagnosis of prostate cancer. However, it still lacks simple, high-precision and wide-ranging sarcosine detection methods. In this work, a Ti3C2TX/Pt–Pd nanocomposite with high stability and excellent electrochemical performance has been synthesized by a facile one-step alcohol reduction and then used on a glassy carbon electrode (GCE) with sarcosine oxidase (SOx) to form a sarcosine biosensor (GCE/Ti3C2TX/Pt–Pd/SOx). The prominent electrocatalytic activity and biocompatibility of Ti3C2TX/Pt–Pd enable the SOx to be highly active and sensitive to sarcosine. Under the optimized conditions, the prepared biosensor has a wide linear detection range to sarcosine from 1 to 1000 µM with a low limit of detection of 0.16 µM (S/N = 3) and a sensitivity of 84.1 µA/mM cm2. Besides, the reliable response in serum samples shows its potential in the early diagnosis of prostate cancer. More importantly, the successful construction and application of the amperometric biosensor based on Ti3C2TX/Pt–Pd will provide a meaningful reference for detecting other cancer biomarkers.  相似文献   
5.
近年来,随着社会环保意识的迅速提高以及对可再生能源利用能力的大幅增强,以燃料电池和电解池为代表的电化学技术已经逐渐在能源的存储、转化和利用方面发挥着不可或缺的独特作用.其中,固态氧化物电解池经过多年的发展,在装置成本和工作效率上取得了长足的进步,在储能转化方面具有重要的潜力.与此同时,伴随着《巴黎协定》签订以来各国的“碳中和”路线图逐渐出台,利用相对廉价易得的可再生电能,将二氧化碳(CO2)和甲烷(CH4)等碳-(C1)分子电解转化为高附加值的可再生燃料(如水煤气、乙烯等),对于碳中和目标的实现具有重要的意义.因此,C1分子电化学转化的研究成为了当下重点关注的研究领域,许多重要的研究成果和技术进步在过去几年中不断涌现.固态氧化物电解池作为一种代表性的C1分子电解和转化平台,也日渐引起相关领域研究人员的关注和兴趣.与传统的C1分子催化转化方法相比,基于固态氧化物电解池的电解转化技术具有两个重要优点:高能量转换效率与体系抗中毒能力.这两个特性作为体系稳健性的基石,保障了C1分子转化为可再生燃料的反应过程的长期可持续性.本文首先简要回顾了固态氧化物电解池的前沿技术与发展,并从电解池系统分类、反应体系的特征和反应体系发展的前景与挑战这三个方面,简要介绍了近年来基于固态氧化物电解池体系的C1分子电化学转化的代表性工作.CO2与CH4作为廉价易得的C1分子的代表,其转化因其反应分子惰性及反应过程不可控性而广受研究者关注,本文重点关注了在固态氧化物电解池中CO2,CO2/H2O和CH4三个体系的电化学反应过程和近期研究进展,希望可为相关研究人员未来设计更合适的催化剂和构建更优的电解池结构提供有益的参考.本文还针对目前固态氧化物电解池体系在C1分子转化领域所面临的挑战,提出了未来的一些可能的研究方向,以期助力研究者在不远的将来实现C1分子电解生产可再生燃料的实用化.  相似文献   
6.
7.
Oil refinery is one of the fast growing industries across the globe and it is expected to progress in the near future. The worldwide increase in the generation of refinery wastewater along with strict environmental regulations in the discharge of industrial effluent, persistent efforts have been devoted to recycle and reuse the treated water. The wastewater from the refining operation leads to serious environmental threat to the ecosystem. Therefore, this study aimed to synthesize silica (SiO2) and calcium carbonate nanoparticles (CaCO3) in the reduction of organics from refinery wastewater. The synthesized nanoparticles were employed in the reduction of chemical oxygen demand (COD) from refinery wastewater by studying the influence of solution pH, contact time, dosage of nanoparticles and stirring speed on adsorption performance. From the batch experimental studies, the optimized processing conditions for the reduction of COD using SiO2 nanoparticles are pH 4.0, dosage 0.5 g, stirring speed 125 rpm and 90 min stirring time, and the corresponding values for CaCO3 nanoparticles are pH 8.0, dosage 0.4 g, stirring speed 100 rpm and 90 min stirring time. The study demonstrates that SiO2 and CaCO3 nanoparticles have a promising future in the reduction organics from refinery wastewater in different pH regimes.  相似文献   
8.
《Mendeleev Communications》2022,32(4):520-522
Investigations of nanocomposite thin films based on polyarylene- phthalide, single-walled carbon nanotubes and graphene oxide have been carried out. Using these films as a transport layer, field-effect transistors were assembled and their output and transfer characteristics were measured. The mobility of charge carriers was estimated and the obtained values are as follows: μPAP/GO = 0.020 cm2 V?1 s?1 and μPAP/SWCNT = 0.071 cm2 V?1 s?1.  相似文献   
9.
Fabrication of bioactive nanomaterials with improved stability and low toxicity towards healthy mammalian cells have recently been a topic of interest. Bioactive metal nanomaterials such as silver nanoparticles (AgNPs) tend to lose their stability with time and become toxic to some extent, limiting their biological applications. AgNPs were separately encapsulated and loaded on the surface of a biocompatible polydopamine (PDA) to produce Ag-PDA and Ag@PDA nanocomposites to unravel the issue of agglomeration. PDA was coated through the self-polymerization of dopamine on the surface of AgNPs to produce Ag-PDA core-shells nanocomposites. For Ag@PDA, PDA spheres were first designed through self-polymerization of dopamine followed by in situ reduction of silver nitrate (AgNO3) without any reductant. AgNPs sizes were controlled by varying the concentration of AgNO3. The TEM micrograms showed monodispersed PDA spheres with an average diameter of 238 nm for Ag-PDA and Ag@PDA nanocomposites. Compared to Ag@PDA, Ag-PDA nanocomposites have shown insignificant toxicity towards human embryonic kidney (HEK-293T) and human dermal fibroblasts (HDF) cells with cell viability of over 95% at concentration of 250 µg/mL. A excellent antimicrobial activity of the nanocomposites was observed; with Ag@PDA possessing bactericidal effect at concentration as low as 12.5 µg/mL. Ag-PDA on the other hand were only found to be bacteriostatic against gram-positive and gram-negative bacteria was also observed.  相似文献   
10.
刘晓艳  王磊  童祎 《中国物理 B》2022,31(1):16102-016102
Most amorphous carbon(a-C)applications require films with ultra-thin thicknesses;however,the electronic structure and opto-electronic characteristics of such films remain unclear so far.To address this issue,we developed a theoretical model based on the density functional theory and molecular dynamic simulations,in order to calculate the electronic structure and opto-electronic characteristics of the ultra-thin a-C films at different densities and temperatures.Temperature was found to have a weak influence over the resulting electronic structure and opto-electronic characteristics,whereas density had a significant influence on these aspects.The volume fraction of sp3 bonding increased with density,whereas that of sp2 bonding initially increased,reached a peak value of 2.52 g/cm3,and then decreased rapidly.Moreover,the extinction coefficients of the ultra-thin a-C films were found to be density-sensitive in the long-wavelength regime.This implies that switching the volume ratio of sp2 to sp3 bonding can effectively alter the transmittances of ultra-thin a-C films,and this can serve as a novel approach toward photonic memory applications.Nevertheless,the electrical resistivity of the ultra-thin a-C films appeared independent of temperature.This implicitly indicates that the electrical switching behavior of a-C films previously utilized for non-volatile storage applications is likely due to an electrically induced effect and not a purely thermal consequence.  相似文献   
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