Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Editor-in-Chief: Peter Gregory, Deputy Editors: Martin Ottmar, Carolina Novo da Silva, Lorna Stimson
Online ISSN: 1521-4095
Associated Title(s): Advanced Energy Materials, Advanced Engineering Materials, Advanced Functional Materials, Advanced Healthcare Materials, Advanced Optical Materials, Particle & Particle Systems Characterization, Small
Recently Published Articles
- 25th Anniversary Article: Bulk Heterojunction Solar Cells: Understanding the Mechanism of Operation
Alan J. Heeger
Article first published online: 6 DEC 2013 | DOI: 10.1002/adma.201304373
The operation of bulk heterojunction (BHJ) solar cells is reviewed. Ultrafast charge transfer arises from fundamental quantum uncertainty as expressed by the uncertainty principle; mobile charges are generated directly by ultrafast charge transfer. Sweep-out of the mobile carriers by the internal field prior to recombination is essential to obtain a high performance, especially a high fill factor.
- A Multilevel Intermediate-Band Solar Cell by InGaN/GaN Quantum Dots with a Strain-Modulated Structure
Liwen Sang, Meiyong Liao, Qifeng Liang, Masaki Takeguchi, Benjamin Dierre, Bo Shen, Takashi Sekiguchi, Yasuo Koide and Masatomo Sumiya
Article first published online: 6 DEC 2013 | DOI: 10.1002/adma.201304335
Multiple stacked InGaN/GaN quantum dots are embedded into a InGaN p-n junction to develop multi-level intermediate-band (MIB) solar cells. IBs transition is evidenced from both experiment and theoretical calculations. The MIB solar cell shows a wide photovoltaic response from the UV to the near-infrared region. This work opens up an interesting opportunity for high-efficiency IB solar cells in the photovoltaic field.
- Optical Wavelength Filters Based on Photonic Confinement in Semiconductor Nanowire Homojunctions
Jian Ye, Chuang Zhang, Chang-Ling Zou, Yongli Yan, Jianmin Gu, Yong Sheng Zhao and Jiannian Yao
Article first published online: 5 DEC 2013 | DOI: 10.1002/adma.201303482
An optical wavelength filter at the nanoscale can be fabricated with semiconductor nanowire homojunctions based on photonic confinement in the nanowire channels with different diameters. By assembling the nanowire homojunctions with short-pass functions, and crossed junctions with long-pass functions, multichannel wavelength filters are set up for dividing the UV and visible green light signals and route them into the designated output ports.
- Alignment-Free Three-Dimensional Optical Metamaterials
Yang Zhao, Jinwei Shi, Liuyang Sun, Xiaoqin Li and Andrea Alù
Article first published online: 5 DEC 2013 | DOI: 10.1002/adma.201304379
Three-dimensional optical metamaterials based on multilayers typically rely on critical vertical alignment to achieve the desired functionality. Here we analyze and experimentally demonstrate the conditions under which three-dimensional metamaterials with different functionalities may be realized without constraints on alignment. Our study allows releasing alignment constraints for multilayered metamaterials, while preserving their anomalous interaction with light.
- Controllable Co-segregation Synthesis of Wafer-Scale Hexagonal Boron Nitride Thin Films
Chaohua Zhang, Lei Fu, Shuli Zhao, Yu Zhou, Hailin Peng and Zhongfan Liu
Article first published online: 5 DEC 2013 | DOI: 10.1002/adma.201304301
A facile and scalable co-segregation method is used to grow hexagonal boron nitride (h-BN) thin films from B- and N-containing metals. By annealing the sandwiched metal substrates in vacuum, sub-monolayer h-BN flakes, monolayer h-BN films, and multilayer h-BN thin films of varying thickness are successfully prepared. This approach follows an underneath-growth mode and exhibits good thickness- and location-control.