Novel CuO/Cu2O hollow polyhedrons with porous shells were fabricated by thermal decomposition of coordination compound [Cu3(btc)2]n (btc = benzene-1,3,5-tricarboxylate) polyhedrons at 350 °C. When tested as anode materials for lithium-ion batteries, these hollow polyhedrons exhibited a reversible lithium storage capacity as high as 740 mA h g(-1) at 100 mA g(-1) after 250 cycles even if the charge-discharge process is stopped for one week during the test time.

Photovoltaic conversion of solar energy into electricity is an alternative way to use renewable energy for sustainable energy production. The great demand of low-cost and efficient solar cells inspires research on solution-processable light-harvesting materials. Antimony trisulfide (Sb 2 S 3) is a promising light-harvester for photovoltaic purposes. Here we report on the in situ grown monolayer of preferentially oriented, large Sb 2 S 3 single-crystalline cuboids on a polycrystalline titania (TiO 2) nanoparticle film. A facile, oriented seed-assisted solutionprocessing method is used, providing the Sb 2 S 3 /TiO 2-based bulk/nano-planar heterojunction with a preferred structure for efficient planar solar cells. An orientation-competing-epitaxial nucleation/growth mechanism is proposed for understanding the growth of the Sb 2 S 3 singlecrystalline cuboids. With an organic hole transporting material, the stable solar cell of the heterojunction yields a power conversion efficiency of 5.15% (certified as 5.12%). It is found that the [221]-oriented Sb 2 S 3 cuboids provide highly effective charge transport channels inside the Sb 2 S 3 layer.

Since the 1990s, we have witnessed remarkable progress in organic semiconductor technology.[1] In particular, reasonably high carrier mobilities, exceeding those of amorphous silicon, were observed in thin-film transistors fabricated from a single crystal of rubrene. [2] In general, it is difficult to fabricate single crystals of aromatic compounds; therefore, zone-melt and Bridgeman crystal-growth [3] or vacuum crystal-growth techniques [4] are indispensable. Polycrystalline thin films are relatively easy to fabricate and suitable for practical devices. High carrier mobilities-of the order of 1 cm 2 V -1 s -1 -have been observed in field-effect transistor (FET) devices based on polycrystalline pentacene thin films. [5] However, defects and domain boundaries affect the carrier transport in aromatic polycrystalline thin films; therefore, the crystal growth under the vacuum process is rigorously controlled.[6]Device fabrication with a more practical solution process has been investigated. As well as conjugated polymers, [7] precursor methods in which thin films fabricated using soluble precursors are transformed to polycrystalline thin films by thermal treatment, [8] and solution-processable pentacene and anthradithiophene derivatives, which form polycrystalline thin films using a spin-coat method, have been investigated.[9]The field-effect mobilities in these studies are of the order of 10 -2 cm 2 , and the carrier mobility is increased up to 0.1 ≈ 1 cm 2 V -1 s -1 by thermal treatment. [8,9] The optimum mobility is lower than those of the FET devices fabricated using vacuum deposition; the device characteristics strongly depend upon the film morphology, because the organic semiconductor thin films fabricated by the solution process have many defects and exhibit low carrier mobility.Liquid-crystalline semiconductors are also possible materials for solution-processable semiconductors. The bulk carriertransport properties have been investigated in discotic columnar, [10,11] smectic, [12][13][14] nematic, [15,16] and cholesteric [17] phases by using the time-of-flight (TOF) technique and pulse-radiolysis time-resolved microwave conductivity. Recently, high hole drift mobilities exceeding 0.1 cm 2 V -1 s -1 have been reported in the highly ordered smectic phases of alkynylquaterthiophene and dithienylbenzene derivatives; [18,19] furthermore a high microscopic band mobility exceeding 1 cm 2 V -1 s -1 has also been observed in the columnar phase of hexabenzocoronene derivatives.[20]Liquid-crystal materials are generally soluble in organic solvents because of their alkyl chains; therefore, solution-processable liquid-crystalline semiconductors have recently been synthesized and applied to light-emitting diode (LED) [21] and FET devices, [22,23] although, FET devices can also be fabricated by vacuum deposition of liquid-crystalline semiconductors. [24] In discotic systems, the zone-cast technique has been utilized for FET devices that exhibited p-type operation with a carrier mobility of the order of 10 -2 cm 2 V -1 s -1 ...

Organic semiconductors (OSCs) are characteristic of long spin-relaxation lifetime due to weak spin-orbit interaction and hyperfine interaction. However, short spin diffusion length and weak magnetoresistance (MR) effect at room temperature (RT) was commonly found on spin valves (SVs) using an organic spacer, which should be correlated with low carrier mobility of the OSCs. Here, N-type semiconducting polymer P(NDI2OD-T2) with high carrier mobility is employed as the spacer in the SV devices. Exceedingly high MR ratio of 90.0% at 4.2 K and of 6.8% at RT are achieved, respectively, via improving the interface structure between the polymer interlayer and top cobalt electrode as well as optimal annealing of manganite bottom electrode. Furthermore, we observe spin dependent transport through the polymeric interlayer and a large spin diffusion length with a weak temperature dependence. The results indicate that this polymer material can be used as a good medium for spintronic devices.

A facile strategy to fabricate FeCo nanocrystals with nitrogen-doped graphene shells has been designed, which involves one-step thermal decomposition of Prussian blue analogue (PBA) Fe3[Co(CN)6]2 spheres. The as-prepared product can be used as a non-precious-metal catalyst with a highly efficient catalytic activity and a magnetically separable capability in the reduction of 4-nitrophenol.

The controlling of molecular orientation and structural ordering of organic semiconductors is crucial to achieve high performance electronic devices. In this work, large‐area highly oriented and ordered films of an excellent electron transporter Poly{[N,N′‐bis(2‐octyldodecyl)‐1,4,5,8‐naphthalenedicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (P(NDI2OD‐T2)) are achieved by improved solution‐cast in high magnetic field. Microstructural characterizations reveal that the chain backbones of P(NDI2OD‐T2) are highly aligned along the applied magnetic field in the films. Based on the synchrotron‐based X‐ray diffraction analysis of the polymer films cast from different solvents, a mechanism which controls the alignment process is proposed, which emphasizes that molecular aggregates of P(NDI2OD‐T2) preformed in the solution initiate magnetic alignment and finally determine the degree of film texture. Furthermore, the time‐modulated magnetic field technique is utilized to effectively control the orientation of π‐conjugated plane of the backbones, thus the degree of face‐on molecular packing of P(NDI2OD‐T2) is enhanced significantly. Thin film transistors based on the magnetic‐aligned P(NDI2OD‐T2) films exhibit an enhancement of electron mobility by a factor of four compared to the unaligned devices, as well as a large mobility anisotropy of seven.

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5-Hexyl-5''-hexynyl-2,2':5',2''-terthiophene exhibits the smectic E phase below 200 degrees C and does not crystallize when it is cooled to -100 degrees C. Between 200 and -100 degrees C, non-dispersive transport is observed for holes and electrons with time-of-flight spectroscopy. Over the entire temperature range, the electron mobility is approximately twice as high as that of the hole. The hole and electron transport characteristics in the smectic phase below 0 degrees C are explained by the Gaussian disorder model, which was proposed for amorphous organic semiconductors. The disorder parameters, sigma and Sigma, are almost the same for holes and electrons. However, the pre-exponential parameter mu(0) for the electron is twice as large as that for the hole, which can be attributed to the difference in the extension of the LUMO of the molecules. The energetic disorder sigma is primarily determined by the disorder in the orientation of the permanent dipoles of liquid crystal molecules.