A single‐junction polymer solar cell with an efficiency of 10.1% is demonstrated by using deterministic aperiodic nanostructures for broadband light harvesting with optimum charge extraction. The performance enhancement is ascribed to the self‐enhanced absorption due to collective effects, including pattern‐induced anti‐reflection and light scattering, as well as surface plasmonic resonance, together with a minimized recombination probability.

The photoconductive characteristics of CdS single nanoribbons were investigated. The device characteristics, including spectral response, light intensity response, and time response, were studied systematically. It is found that CdS nanoribbon has the response speed substantively faster than those ever reported for conventional film and bulk CdS materials and the size of nanoribbons has a significant influence on the response speed with smaller CdS nanoribbons showing higher response speed. The high photosensitivity and high photoresponse speed are attributable to the large surface-to-volume ratio and high single-crystal quality of CdS nanoribbons and the reduction of recombination barrier in nanostructures. Measurements in a different atmosphere demonstrate that the absorption of ambient gas (mainly oxygen) can significantly change the photosensitivity of CdS nanoribbons through trapping electrons from the nanoribbons.

Patient-related factors are as important as procedure-related factors in determining high-risk predictors for post-ERCP overall complications and pancreatitis. However, the risk factors for asymptomatic hyperamylasemia may be mostly procedure related.

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Recent advances in organic light-emitting diodes toward smart lighting and displays are reviewed in terms of materials, devices, fabrication and applications.

As an important II-VI semiconductor, ZnO has attracted increasing interests owing to its unique properties such as wide band-gap (3.37 eV) and large exciton binding energy (60 meV).[1] ZnO has shown great potential in optoelectronic devices such as light emitting diodes (LED) and laser diodes (LDs) operating in the short-wavelength or UV region.[2]Compared to their thin-film counterparts, [3][4] nanoscale devices assembled on free-standing nanowires [5][6][7][8][9][10] could enable new functions, high efficiency, enhanced performance, and diverse applications. [11][12][13][14][15][16][17][18][19][20] As in thin-film devices, the success of nanodevices similarly relies on the capability of controlling the transport and electrical properties of the selected materials. Doping via introducing electron donor or acceptor elements into the host crystal is a successful approach in thin-film or planar electronic/optoelectronic devices. However, such doping approach remains a challenge for nanostructured materials. To date, while n-and p-type dopings have been achieved in Si, [11][12] InP, [13] CdS, [14] and GaN [15] nanowires/ nanoribbons, many issues of doping, such as control of doping type and conductivity, remain largely untapped or unresolved. For ZnO nanostructures, group III elements (Al, Ga, or In) are commonly used to substitute Zn to induce n-type conductivity. The success of doping is often accompanied and characterized by changes in optical, electrical, and/or structural properties of ZnO nanostructures. For example, Al-doped ZnO nanowires exhibited a blue shift from 3.29 to 3.34 eV in the cathodoluminescent (CL) spectra.[21] Ga 2 O 3 was also employed to dope n-type ZnO nanofibers grown in a vaporphase transport process. [22] however switched to n-type after two months storage in an ambient environment. Despite the considerable efforts, rational synthesis of ZnO nanostructures with tunable n-type conductivity is not available. The as-synthesized ZnO nanostructures are often randomly oriented, and thus have limited applications in optoelectronic devices. Therefore, it is necessary to have a better understanding of the doping efficiency and transport properties of ZnO nanostructures. Herein, we report a controlled growth and doping process of well-aligned ZnO nanowire (NW) arrays via thermal evaporation. The growth direction of ZnO NWs was found to depend on the dopant content, and NW conductivity could be varied over two orders of magnitude. The electrical properties of ZnO NWs were characterized using single-nanowire field-effect transistors (FETs). Figure 1 shows the electron microscopy images of ZnO NW arrays synthesized on a-plane sapphire substrates. The content of Ga 2 O 3 in the source mixtures was varied from 0 to 1 at %. The representative NWs synthesized with 0, 0.2, and 1 at % of Ga 2 O 3 are denoted as samples A, B, and C, respectively. Both the undoped (Fig. 1a and b) and Ga-doped (Fig. 1c) ZnO NWs are aligned vertically on the substrates, and uniform over a large area. The NWs have a uniform dia...

This review summarizes the recent achievements in flexible OLEDs involving transparent conductive electrodes, device fabrication, light extraction technologies, as well as encapsulation methods.

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