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1.
采用氯化锌(ZnCl_(2))修饰镉基CdSe/ZnS蓝光量子点(B-QD)薄膜,发现与量子点表面结合力更强的ZnCl_(2)能够部分取代量子点长链配体油酸,有效钝化量子点表面缺陷,提高薄膜的荧光量子效率(PLQY)。此外,由于ZnCl_(2)具有偶极作用,使量子点真空能级提高0.2 eV,一方面可改善电子和空穴载流子注入平衡,另一方面可有效降低发光器件的启亮电压,提高器件的发光寿命。这种无机配体修饰量子点薄膜的方法可能为解决蓝光量子点发光二极管(B-QLEDs)因空穴注入困难和量子点表面缺陷导致器件性能不高的问题提供一个有效思路。  相似文献   
2.
A comparison of the analytical performances of four different (bio)sensor designs in H2O2 determination is discussed. The (bio)sensor designs developed were based on the use of (i) multiwalled carbon nanotubes (MWCNT), zinc oxide nanoparticles (ZnONP), prussian blue (PB); (ii) MWCNT, ZnONP, PB and ionic liquid (IL); (iii) MWCNT, ZnONP and horseradish peroxidase (HRP) and (iv) MWCNT, ZnONP, HRP and IL modified glassy carbon electrode (GCE). A performance comparison of (bio)sensors showed that the one based on HRP/IL-MWCNT-ZnONP/GCE showed the best analytical characteristics with a linear dynamic range of 9.99×10−8–7.55×10−4 M, detection limit of 1.37×10−8 M and sensitivity of 17.00 μA mM−1.  相似文献   
3.
Herein, we report a facile method for synthesizing MoCo-layered double hydroxide (LDH) nanosheets employing Prussian blue analog (PBA) as the precursor. The introduction of Mo in Co-LDH modulates the electronic structure, increases the number of active sites and electrochemical surface area to improve the hydrogen evolution, oxygen evolution, and overall water splitting activity. As a result, PBA-derived Mo0.25Co0.75-LDH nanosheets demonstrated 10 mA cm?2 current density at only 220 mV and 115 mV overpotentials for OER and HER, respectively. The overall water splitting was attained at 1.52 V cell voltage for 10 mA cm?2 current density.  相似文献   
4.
以锰金属有机框架(Mn?MOF)为前驱体制备了Mn2O3微球。所得微球大小约为4μm,尺寸均匀,具有完美的球形结构,表面粗糙,结晶度好,产率较高。同时,研究了Mn?MOF衍生的Mn2O3微马达在不同条件下的运动性能以及对甲基蓝的降解性能。Mn2O3微马达运动性能优异,在10%的H2O2溶液中,其运动速度可达81.32μm·s-1。实验结果表明,加入H2O2后,Mn2O3微马达在5 min内通过降解作用可有效去除MB。  相似文献   
5.
Degradation of trypan blue (TB) by persulfate/CuNPs system was investigated as a function of TB concentration, persulfate concentration, CuNPs concentration, pH, and reaction temperature in aqueous solution. The rate of the decolorization and destruction of aromatic ring were studied spectrophotometrically. The dye mineralization was performed with potassium dichromate for the determination of chemical oxygen demand (COD) in solution. The blue color reaction mixture became red-chocolate, purple, light blue to dark blue as a function of time. The CuNPs acted as an activator of K2S2O8 and generates various reactive oxygen and/or sulphur species. Decolorization of dye starts due to the cleavage of azo bond by the generated radical species. The role of sulfate radicals (SO4?-), and hydroxyl radicals (HO?) were established by using different radical scavengers. Degradation and mineralization of dye follows first-order kinetics. These results can support the design of remediation processes and also assist in predict their fate in environment.  相似文献   
6.
Graft copolymers show microphase separated structure as seen in block copolymers and have lower intrinsic viscosity than block copolymers because of a branching structure. Therefore, considering molding processability, especially for polymers containing rigid segments, graft copolymers are useful architectures. In this work, graft copolymers containing rigid poly(diisopropyl fumarate) (PDiPF) branches were synthesized by full free‐radical polymerization process. First, synthesis of PDiPF macromonomers by addition‐fragmentation chain transfer (AFCT) was investigated. 2,2‐Dimethyl‐4‐methylene‐pentanedioic acid dimethyl ester was found to be an efficient AFCT agent for diisopropyl fumarate (DiPF) polymerization because of the suppression of undesired primary radical termination, which significantly took place when common AFCT agent, methyl 2‐(bromomethyl)acrylate, was used. Copolymerization of PDiPF macromonomer with ethyl acrylate accomplished the generation of the graft copolymer having flexible poly(ethyl acrylate) backbone and rigid PDiPF branches. The graft copolymer showed a microphase separated structure, high transparency, and characteristic thermal properties to PDiPF and poly(ethyl acrylate). © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2474–2480  相似文献   
7.
8.
In this work, the modified Prussian blue (PB) film showed more stable performance in alkaline solution by one‐step electrodepositon of PB with tris(hydroxymethyl) aminomethane (Tris) on screen‐printed electrode (SPE). The morphology and structure of the modified Tris‐PB/SPE was characterized by scanning electronic microscopy, infra spectroscopy, Raman spectroscopy and X‐ray diffraction. It was inferred that the Tris particles embedded in the PB deposit layer resulted in the change of PB structure and improve its stability in alkaline solution. And then, the modified Tris‐PB/SPE was applied in the detection of Glycosylated hemoglobin (HbA1c). The optimum experimental conditions are pH 7.5, 100 mV/s, 4 μL FAOD and 5 min reaction time. The linearship of HbA1c is i=22.90 C+101.9 in the range of 0.1–2 mmol/L. Comparing with PB/SPE, Tris‐PB/SPE shows better sensitivity and recovery.  相似文献   
9.
Due to the difficulty in achieving high efficiency and high color purity simultaneously, blue emission is the limiting factor for the performance and stability of OLEDs. Since 2003, we have been working on organic light‐emitting diodes (OLEDs), especially on blue light. After a series of molecular designs, novel strategies have been proposed from different aspects. At first, highly efficient deep blue emission could be achieved through molecular design with highly twisted structure to suppress fluorescence quenching and redshift. Deep blue emitters with high efficiency in solid state, a twisted structure with aggregation induced emission (AIE) characteristics was incorporated to inhibit molecular aggregation, and triplet‐triplet fusion (TTF) and hybridized localized charge transfer (HLCT) were adopted to increase the ratio of triplet exciton used. Secondly, a highly efficient blue OLED could be achieved through improving charge transport. New electron transport materials (ETMs) with wide band gap were developed to control charge transport balance in devices. Thirdly, a highly efficient deep blue emission could be achieved through a mesoscopic structure of out‐coupling layer. A mesoscopic photonic structured organic thin film was fabricated on the top of metal electrode by self‐aggregation in order to improve the light out‐coupling efficiency.  相似文献   
10.
Photocatalysis has been extensively studied due to its potential ability to avoid the excessive use of chemical reagents and reduce the energy consumption by employing solar energy. Moreover, to alleviate the reduction in the membrane permeation selectivity, separation efficiency, and membrane service life caused by the emerging micro-pollutants and membrane fouling, membrane technology is often coupled with microbial, electrochemical, and catalytic processes. However, although physical/chemical cleaning and membrane module replacement can overcome the inherent limitations caused by membrane fouling and other membrane separation processes, high operating costs limit their practical applications. In this review, common preparation methods for TiO2 photocatalytic membranes are described in detail, and the main approaches to enhancing their photocatalytic performance are discussed. More importantly, the mechanism of the TiO2 photocatalytic membrane antifouling process is elucidated, and some applications of photocatalytic membranes in other areas are described. This review systematically outlines future research directions in the field of photocatalytic membrane modification, including metal and non-metal doping, fabrication of heterojunction structures, control over reaction conditions, increase in hydrophilicity, and increase in membrane porosity.  相似文献   
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