Light‐controlled electrical behavior of polymer/nanoparticle hybrid system in ambient condition is demonstrated. By embedding gold nanoparticles (Au NPs) in a poly(3‐hexylthiophene) (P3HT) matrix, the photoresponses of the nanocomposite films are enhanced. The electrical behavior of the P3HT/Au NPs nanocomposite transistors and inverters are tuned over a wide range in depletion mode. UV‐visible absorption spectroscopy, ultraviolet photoelectron spectroscopy (UPS), and steady‐state photoluminescence (PL) spectroscopy are used to analyze the nanocomposite films. The findings provide a better understanding of light‐induced threshold voltage shifts of P3HT‐based field‐effect transistors and inverters and demonstrate their potential applications in electronic signal modulation for solution‐processed integrated circuits. 相似文献
Transition metal dichalcogenides (TMDC) are important representatives in the emerging field of two‐dimensional materials. At present their combination with molecular films is discussed as it enables the realization of van der Waals bound organic/inorganic hybrids which are of interest in future device architectures. Here, we discuss the potential use of molybdenum disulfide (MoS2) as supporting substrate for the growth of well‐defined, crystalline organic adlayers. By this means, hybrid systems between the TMDC surface and organic compounds can be prepared, allowing for the profound investigation of mutual optical and electronic coupling mechanisms. As model system, we choose pentacene and perfluoropentacene as prototypical organic semiconductors and analyze their film formation on MoS2(001) surfaces. In both cases, we observe smooth, crystalline film growth in lying molecular configuration, hence enabling the preparation of well‐defined hybrid systems. By contrast, on defective MoS2 surfaces both materials adopt an upright molecular orientation and exhibit distinctly different film morphologies. This emphasizes the importance of highly ordered TMDC surfaces with low defect density for the fabrication of well‐defined hybrid systems. 相似文献
1D nanostructured metal oxides with porous structure have drawn wide attention to being used as high‐performance anode materials for lithium‐ion batteries (LIBs). This study puts forward a simple and scalable strategy to synthesize porous NiO nanorods with the help of a thermal treatment of metal‐organic frameworks in air. The NiO nanorods with an average diameter of approximately 38 nm are composed of nanosized primary particles. When evaluated as anode materials for LIBs, an initial discharge capacity of 743 mA h g?1 is obtained at a current density of 100 mA g?1, and a high reversible capacity is still maintained as high as 700 mA h g?1 even after 60 charge–discharge cycles. The excellent electrochemical performance is mainly ascribed to the 1D porous structure. 相似文献
We have demonstrated a simple near‐infrared (NIR) photodetector (PD) based on charge transfer complex (CTC) formed in molybdenum trioxide (MoO3) doped N,N′‐di(naphthalene‐1‐yl)‐N,N′‐diphenyl‐benzidine (NPB), which shows a photocurrent of about 0.35 A/cm2 at –3 V under 980 nm illumination. The existence of CTC formation promotes photocurrent generation which is investigated by comparison with MoO3 doped 2‐methyl‐9,10‐di(2‐naphthyl)anthracene (MADN) film which has no CTC absorption. It can be evolved that this kind of simple‐structure photodetector has potential application in the near‐infrared (NIR) detection area. It is shown in this Letter that although both MoO3 and NPB have larger energy gaps of about 3 eV and weak absorption in the NIR region, the charge transfer complexes formed by mixing the two materials show an extra absorption band and good photoelectric response in the NIR region.
Low‐voltage‐control circuit is one of the most important parts of the modern electrical control system due to the avoidance of operation risk and easy automation. Here, based on a C60: m‐MTDATA bulk heterojunction, a blue‐light‐sensitive organic photodiode (OPD) is explored for the development of flexible low‐voltage‐control circuit. The control of circuit under 2000 V high voltage is achieved. The influences of the organic‐layer thickness, the donor/acceptor volume ratio and the matching of energy levels on the photocurrent are investigated. The maximum light/dark current ratio and current transfer ratio of 1.3 × 104 and 1.3% are achieved, respectively. The highest photoresponse is up to 130 mA/W, markedly higher than some commercial inorganic photodiodes. This device could also be used as flexion and mechanical force sensors with the current density changing under different bending conditions. Therefore, this sort of OPD has a promising application in low‐voltage‐controlled, high‐voltage‐endurable hands for intelligent robots. 相似文献
Combined small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) is a powerful technique for the study of materials at length scales ranging from atomic/molecular sizes (a few angstroms) to the mesoscopic regime (~1 nm to ~1 µm). A set‐up to apply this technique at high X‐ray energies (E > 50 keV) has been developed. Hard X‐rays permit the execution of at least three classes of investigations that are significantly more difficult to perform at standard X‐ray energies (8–20 keV): (i) in situ strain analysis revealing anisotropic strain behaviour both at the atomic (WAXS) as well as at the mesoscopic (SAXS) length scales, (ii) acquisition of WAXS patterns to very large q (>20 Å?1) thus allowing atomic pair distribution function analysis (SAXS/PDF) of micro‐ and nano‐structured materials, and (iii) utilization of complex sample environments involving thick X‐ray windows and/or samples that can be penetrated only by high‐energy X‐rays. Using the reported set‐up a time resolution of approximately two seconds was demonstrated. It is planned to further improve this time resolution in the near future. 相似文献
Mass production and commercial availability are prerequisites for the viability and wide application of MoS2. Here, we demonstrate enhanced grindstone chemistry for a one‐step synthesis of biofunctionalized MoS2. By adding a SiO2 auxiliary agent the exfoliation efficiency increases from 16.23% to 58.59% and a rapid and high‐yield exfoliation of MoS2 is seen. SiO2 exhibits a fragmentation effect, which reduces the lateral size and facilitates the exfoliation of MoS2, thus inducing a high‐efficient paradigm in the top‐down fabrication of biofunctionalized MoS2 nanosheets. The as‐prepared MoS2‐chitosan (MoS2‐CS) nanosheets display complete disaggregation and homogeneous dispersion, as well as a high content of chitosan (ca. 20 wt%). As a proof‐of‐concept application, the MoS2‐CS nanosheets act as a biosorbent for PbII removal, exhibiting a good adsorption capacity and recyclability. This green and facile enhanced grindstone chemistry with minimal use of organic solvents and high‐throughput efficiency can be extended to the fabrication of other biocompatible inorganic 2D analogues for a variety of applications. 相似文献
The integration of unique functionality into mesoporous organosilica hybrid carriers is an important issue in solving the challenges of dual/multi delivery for combined therapy with drugs with a distinct therapeutic effects. Newly designed mesoporous organosilica hybrid microcarriers (HMCs) are synthesized on the basis of the triblock‐copolymer‐templated sol–gel method. The synthesized HMCs, which integrate both heteroaromatic pyridine and diurea functionalities, are combined in a mesoporous organosilica hybrid network to design functional hybrid microcarriers with a range of mechanisms for the pH‐triggered release of two drugs. The drugs include the hydrophilic anticancer therapeutic agent 5‐fluorouracil (5‐FU) and the non‐steroidal hydrophobic anti‐inflammatory drug ibuprofen (IBU). 5‐FU and IBU are encapsulated in the HMCs using multiple hydrogen bonding and electrostatic interaction sites and are delivered under a range of pH conditions. The release of 5‐FU and IBU is tested at pH 5.5 and 7.4. The results show that the release is sensitive to pH. The antitumor activity of the released 5‐FU is evaluated using the MCF‐7 cell line. The released 5‐FU has the capacity to kill cancer cells under acidic pH conditions. 相似文献
Organic light‐emitting diodes (OLEDs) are discussed for electro‐optical integrated devices that are used for optical signal transmission. Organic optical devices including polymeric optical fibers are used for optical communication applications to realize polymeric electro‐optical integrated devices. The OLEDs were fabricated by vacuum process, i.e. the organic molecular beam deposition (OMBD) technique or a solution process on a polymeric or a glass substrate, for comparison. Optical signals faster than 100 MHz have been created by applying pulsed voltage directly to the OLED utilizing rubrene doped in 8‐hydoxyquinolinum aluminum (Alq3), as an emissive layer. OLEDs fabricated by solution process utilizing rubrene doped in carrier‐transporting materials have also discussed. OLEDs utilizing polymeric materials by solution process are also fabricated and discussed. Moving‐picture signals are transmitted utilizing both vacuum‐ and solution‐processed OLEDs, respectively. 相似文献
Complex wax@water@SiO2 multicore capsules are synthesized by combining sol‐gel process and formulation of wax‐in‐water‐in‐oil double emulsions. The inner direct wax‐in‐water emulsion is stabilized with modified silica nanoparticles using limited coalescence occurring in Pickering emulsions. In a second step, this obtained liquid dispersion is emulsified in poly‐dimethylsiloxane (PDMS) using a non ionic surfactant to stabilize the second water/oil interface. Finally, a sol‐gel process is employed to mineralize the as‐generated double emulsions giving rise to wax@water@SiO2 multicore capsules. Due to the wax volume expansion through melting, the as‐synthesized multicore capsules offer thermally stimulated release that is enhanced when surfactant is added in the surrounding continuous oil phase. In addition, the melted wax release can be tuned from a one‐step process to a more sequential dropping mode by varying the mineral precursor tetraethoxy‐orthosilane (TEOS) concentration in the oily phase during mineralization. 相似文献
Graphene‐based phosphorus‐doped carbon (GPC) is prepared through a facile and scalable thermal annealing method by triphenylphosphine and graphite oxide as precursor. The P atoms are successfully doped into few layer graphene with two forms of P–O and P–C bands. The GPC used as anode material for Na‐ion batteries delivers a high charge capacity 284.8 mAh g?1 at a current density of 50 mA g?1 after 60 cycles. Superior cycling performance is also shown at high charge?discharge rate: a stable charge capacity 145.6 mAh g?1 can be achieved at the current density of 500 mA g?1 after 600 cycles. The result demonstrates that the GPC electrode exhibits good electrochemical performance (higher reversible charge capacity, super rate capability, and long‐term cycling stability). The excellent electrochemical performance originated from the large interlayer distance, large amount of defects, vacancies, and active site caused by P atoms doping. The relationship of P atoms doping amount with the Na storage properties is also discussed. This superior sodium storage performance of GPC makes it as a promising alternative anode material for sodium‐ion batteries. 相似文献
Currently, the major commercial white light‐emitting diode (WLED) is the phosphor‐converted LED made of the InGaN blue‐emitting chip and the Ce3+:Y3Al5O12 (Ce:YAG) yellow phosphor dispersed in organic epoxy resin or silicone. However, the organic binder in high‐power WLED may age easily and turn yellow due to the accumulated heat emitted from the chip, which adversely affects the WLED properties such as luminous efficacy and color coordination, and therefore reduces its long‐term reliability as well as lifetime. Herein, an innovative luminescent material: transparent Ce:YAG phosphor‐in‐glass (PiG) inorganic color converter, is developed to replace the conventional resin/silicone‐based phosphor converter for the construction of high‐power WLED. The PiG‐based WLED exhibits not only excellent heat‐resistance and humidity‐resistance characteristics, but also superior optical performances with a luminous efficacy of 124 lm/W, a correlated color temperature of 6674 K and a color rendering index of 70. This easy fabrication, low‐cost and long‐lifetime WLED is expected to be a new‐generation indoor/outdoor high‐power lighting source. 相似文献
Organic optoelectronic devices including organic light‐emitting diodes (OLEDs) and polymer solar cells (PSCs) have many advantages, including low‐cost, mechanical flexibility, and amenability to large‐area fabrication based on printing techniques, and have therefore attracted attention as next‐generation flexible optoelectronic devices. Although almost 100% internal quantum efficiency of OLEDs has been achieved by using phosphorescent emitters and optimizing device structures, the external quantum efficiency (EQE) of OLEDs is still limited due to poor light extraction. Also, although intensive efforts to develop new conjugated polymers and device architectures have improved power conversion efficiency (PCE) up to 8%–9%, device efficiency must be improved to >10% for commercialization of PSCs. The surface plasmon resonance (SPR) effect of metal nanoparticles (NPs) can be an effective way to improve the extraction of light produced by decay of excitons in the emission layer and by absorption of incident light energy within the active layer. Silver (Ag) NPs are promising plasmonic materials due to a strong SPR peak and light‐scattering effect. In this review, different SPR properties of Ag NPs are introduced as a function of size, shape, and surrounding matrix, and review recent progress on application of the SPR effect of AgNPs to OLEDs and PSCs. 相似文献