Institute of Chemistry
Changchun Institute of Applied Chemistry, Chinese Academy Of SciencesNot a member yet
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聚噻吩/绝缘聚合物共混物的形貌调控及电学性能研究
No full text有机半导体因其柔性、轻质、可溶液加工、适合于大面积化制备等优点，在有机电子学器件领域得到了广泛的关注和深入的研究。为了满足工业化应用的需求，进一步降低其成本，提升器件稳定性及电学性能十分必要。鉴于此，半导体/绝缘体聚合物（SP/IP）复合材料应运而生。虽然研究人员目前制备出了高电学性能的SP/IP复合材料，但是对电荷传输增强的物理机制并不清楚，而且甚至不清楚产生这种增强现象的形态学关键特征，这严重制约了这个现象的进一步优化和应用。本论文以半导体聚合物聚（3-己基噻吩）(P3HT)及其共混物为研究对象，重点考察了同组分复合薄膜中，薄膜形貌对材料电学性能的影响；探究了不同绝缘聚合物对P3HT/IP复合薄膜电导率贡献差异的原因及一种新型的聚合物掺杂剂对P3HT的掺杂效果。本论文的主要内容及所取得的创新性成果如下： 首先，以P3HT/PS(聚苯乙烯)共混物为研究对象，研究了薄膜形貌对电导率的影响。...Organic semiconductors have gained wide attention and deep research in the past few years in the field of organic electronic devices due to their advantages of flexibility, light weight, solution processing and large area fabrication. To meet the requirements for industrial application, it is necessary to further reduce cost, and improve stability and device performance. To this end, semiconducting-/insulating polymer (SP/IP) composites emerge. Though researchers have fabricated SP/IP composites with high electrical performance, the physical mechanism for enhanced charge transport is not clear, and even do not know the critical morphological characteristics, which seriously restrict the optimization and application of this phenomenon. Herein, semiconducting polymer, poly(3-hexylthiophene) ..
Significantly Enhancing Grain Growth in Cu2ZnSn(S,Se)(4) Absorber Layers by Insetting Sb2S3, CuSbS2, and NaSb5S8 Thin Films
No full textThe Cu2ZnSn(S,Se)(4) (CZTSSe) has gained extensive attention in thin film solar cells due to their potential as a nontoxic, low-cost, and earth-abundant absorber material, and a rapid increase in power conversion efficiencies has been demonstrated in laboratory. Compared with the most successful hydrazine-based solution process, the nanocrystal-based ink method and non-hydrazine molecular precursor solution approach are more eco-friendly for fabricating high-efficiency CZTSSe solar cells. However, it is hard to obtain a complete large-grain CZTSSe absorber thin film which can facilitate the transport of photogenerated carriers while minimize grain boundary recombination. Here, we present a simple and effective strategy to significantly enhance grain growth of CZTSSe absorber layers by insetting Sb2S3, CuSbS2, and NaSb5S8 thin films. The incorporation of Sb-based thin films can induce grain growth in the selenization process, and did not produce the impurity phase confirmed by XRD patterns and Raman spectra. It was found that the order of the crystal growth promotion ability is Sb2S3 > CuSbS2 > NaSb5S8 under the same experimental conditions. The presented approach can be extended to other solution processes of fabricating CZTSSe solar cells to enhance their microstructural properties, which are critical for applications in CZTSSe absorbers with fine-grain layers
Label-Free Surface-Enhanced Infrared Spectroelectrochemistry Studies the Interaction of Cytochrome c with Cardiolipin-Containing Membranes
No full textInteractions of cytochrome c (cyt c) with cardiolipin (CL)-containing membranes have been revealed to play an important role in inducing early apoptosis. In this paper, we studied the interaction of cyt c with solid-supported CL-containing lipid bilayers by a lable-free spectroelectrochemistry method. The biomimetic membrane was fabricated by fusing cardiolipin-phosphatidylcholine (CL_PC, 1:4) vesicles onto the hydrophobic surface of a preadsorbed 1-dodecanethiol (DT) on a gold electrode (CL_PC/DT/Au). The adsorption of cyt c onto the CL_PC/DT/Au was in-situ studied by cyclic voltammetry (CV) and surface-enhanced Infrared adsorption spectroscopy (SEIRAS). The electrochemistry of Cyt c/CL_PC/DT/Au exhibits the formal potential (E-f) at 0.21 V (vs Ag/AgCl), a positive shift of 190 mV as compared to that of native cyt c adsorbed at the mercaptoundecanoic acid-modified gold electrode (Cyt c/MUA/Au). The potential-induced SEIRA difference spectroscopy discloses that cyt c was loosely adsorbed onto CL_PC/DT/Au in a different orientation and underwent a new beta-sheet formation relative to native cyt c adsorbed onto MUA/Au. It could be the enhanced hydration change of CL-bound cyt c upon oxidization and reduction and the different adsorption orientation that determine the positive shift in its formal potential
End-Group Engineering of Low-Bandgap Compounds for High-Detectivity Solution-Processed Small-Molecule Photodetectors
No full textSeveral pi-conjugated compounds based on diketopyrrolopyrrole and trithiophene substituted with different end groups (alkyl, alkyloxy, and alkylthio) were designed and synthesized for investigation of the material properties and photodetector performance brought by subtle changes in the end groups. Among all, compound 4 with hexylthio groups exhibits the most red-shifted absorption, strongest molecular stacking, highest mobility, and ideal film morphology. These unique properties make it a promising material for use in small-molecule photodetectors. Photodetector SMPD-4 based on compound 4 exhibits broad response from 300 to 900 nm and a high specific detectivity (D*) of 1.3 x 10(13) Jones at 650 nm under -0.1 V. This result is among the best values reported for solution-processed small-molecule photodetectors and even in the same order of conventional silicon photodetector. The molecular structure-material property-device performance relationships are established with these compounds. This work suggests that end-group engineering is a useful method in tuning the material properties and device performance of organic semiconductors
Immobilization of nattokinase-loaded red blood cells on the surface of superhydrophobic polypropylene targeting fibrinolytic performance
No full textA platform for capture and release of drug-loaded red blood cells (RBCs) is demonstrated by utilizing polymer grafted superhydrophobic polypropylene (PP). Combined with micro/nanobinary structures, thermoresponsive polymers, and lectin-saccharides recognition, this platform enables highly efficient capture and release of RBCs loaded with nattokinase, which endows PP with potent fibrinolytic ability
A dextran-platinum(IV) conjugate as a reduction-responsive carrier for triggered drug release
No full textReduction-responsive nano-carriers have been confirmed to be promising for intracellular drug delivery. To develop multifunctional polymer-based drug delivery system, a novel dextran-Pt(IV) conjugate was synthesized by conjugating Pt(IV) to the side chains of the hydrophilic dextran and used for doxorubicin (DOX) delivery. Pt(IV) conjugation could change the hydrophilicity of dextran, leading to the self-assembly of dextran-Pt(IV) conjugates with different morphologies. Pt(IV) segments served as the key components in assembly formation and as the antitumor prodrug. Under a reductive environment, Pt(IV) was found to be reduced to its active Pt(II) form and cleaved from dextran, shifting the hydrophilic-hydrophobic balance of the dextran-Pt(IV) conjugate. The collapse of the assembly structure due to the partial or complete recovery of the hydrophilicity of dextran led to triggered release of DOX. The DOX-loaded dextran-Pt(IV) conjugate obtained by combining the released hydrophobic DOX and recovered hydrophilic Pt(II), was found to be very effective as an antitumor agent as demonstrated in in vitro cytotoxicity evaluations. This DOX-loaded dextran-Pt(IV) conjugate system provided a new strategy to trigger the release of hydrophobic and hydrophilic drugs at the same time via single reduction-responsive control to provide an enhanced anti-tumor effect
Generation of orange and green emissions in Ca2GdZr2(AlO4)(3):Ce3+, Mn2+, Tb3+ garnets via energy transfer with Mn2+ and Tb3+ as acceptors
No full textUtilizing Mn2+ and Tb3+ ions as energy-transfer acceptors, we report a series of emission color-tunable Ca2GdZr2(AlO4)(3):Ce3+, Mn2+, Tb3+ aluminate garnets. Incorporating Mn2+ and Tb3+ into Ca2GdZr2(AlO4)(3):Ce3+ phosphor generates an orange emission band peaking at 572 nm and a green line peaking at 550 nm. The energy transfers from Ce3+ to Mn2+ and Ce3+ to Tb3+ ions are deduced from the spectral overlap between the Ce3+ emission and Mn2+/Tb3+ excitation spectra. Fluorescence decay patterns are studied as a function of Mn2+ and Tb3+ concentration. The calculated values based on the luminescence dynamical process indicate that the intensity ratios of the orange to green bands as a function of Mn2+ concentration are in good agreement with those obtained directly from the emission spectra. We have demonstrated that the color emission as well as the luminescence external quantum yield (20.4-48.9%) can be tuned by precisely controlling the content of Ce3+, Mn2+, and Tb3+. The energy transfer significantly enables the achievement of a broad emission spectrum covering an orange spectral region. It is suitable for near-UV light-emitting diode (LED) excitation
Enhancement of luminescence performance from the alteration of stacking patterns of Pt(II) dendrimers
No full textFour red emission Pt(II) dendrimers, in which the emitting core and dendrons are joined by a flexible alkylene chain, have been designed and synthesized. They exhibit nearly identical emissive wavelength both in photoluminescence in solution and electroluminescence. Improved luminescence performance results from a favourable packing pattern compared with their parents. A maximum current efficiency up to 22.11 cd A(-1), the corresponding power efficiency of 12.29 lm W-1 and EQE of 11.70%, have been recorded in a doped and solution-processed OLED
Interplay between local environments and photoluminescence of Eu2+ in Ba2Zr2Si3O12: blue shift emission, optimal bond valence and luminescence mechanisms
No full textBa2(1-x)Zr2Si3O12(BZSO): xEu(2+) (x = 0.005-0.06) phosphors have been prepared by a high temperature solid state reaction. Using X-ray powder diffraction, the structural properties including the phase purity were analyzed through Rietveld analysis. The BZSO: Eu2+ phosphors exhibit a broad excitation band ranging from 200 to 450 nm, and an intense asymmetric green emission band centered at 501 nm under an excitation of 365 nm. The optimum doping concentration of Eu2+ was found for x = 0.03. The detailed energy transfer mechanism among Eu2+ in BZSO is found to be a dipole-dipole mechanism, and the critical distance (R-C) for the Eu2+ ions calculated by the concentration quenching and spectral overlap methods are 20.45 and 25.83 angstrom, respectively. Furthermore, the unexpected blue shift (from green to cyan) in the emission and the increase in the thermal quenching barrier upon cation substitutions (Ca2+/Sr2+ for Ba2+) in the BZSO: 0.03Eu(2+) system have been investigated, which is due to the variation of the crystal field strength that the 5d orbital of the Eu2+ ion experiences. The underlying mechanism is ascribed to the differences between the average structure and the local coordination environments on the activator ions (Eu2+), as confirmed by the refinement results. Considering the merits of the near-UV light excitation, broad band emission, and good thermal stability, these materials have a potential application as white light emitting diode phosphors
A Platinum Highly Concave Cube with one Leg on each Vertex as an Advanced Nanocatalyst for Electrocatalytic Applications
No full textPlatinum highly concave cubes with one leg on each vertex (HCCLV) enclosed by {750} facets were conveniently synthesized for the first time through a one-pot solvothermal method in a mixed solvent of oleylamine and isopropanol containing platinum(II) acetylacetonate. This method can also be extended to the synthesis of Pt dendrite nanocubes at shorter reaction times. Preferential overgrowth may facilitate the formation of Pt HCCLV in the presence of oleylamine and isopropanol. The Pt HCCLV exhibit excellent electrocatalytic activity for the oxidation of methanol (7.76x) and ethanol (5.46x) compared to commercial Pt black. Furthermore, the Pt HCCLV show higher stability than Pt dendrite nanocubes and commercial Pt black. The Pt HCCLV also remarkably improve the electrochemiluminescence activity of the luminol/H2O2 system