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991.
Cong Chen Yue Jiang Jiali Guo Xiayan Wu Wenhui Zhang Sujuan Wu Xingsen Gao Xiaowen Hu Qianming Wang Guofu Zhou Yiwang Chen Jun‐Ming Liu Krzysztof Kempa Jinwei Gao 《Advanced functional materials》2019,29(30)
A high‐quality polycrystalline SnO2 electron‐transfer layer is synthesized through an in situ, low‐temperature, and unique butanol–water solvent‐assisted process. By choosing a mixture of butanol and water as a solvent, the crystallinity is enhanced and the crystallization temperature is lowered to 130 °C, making the process fully compatible with flexible plastic substrates. The best solar cells fabricated using these layers achieve an efficiency of 20.52% (average 19.02%) which is among the best in the class of planar n–i–p‐type perovskite (MAPbI3) solar cells. The strongly reduced crystallization temperature of the materials allows their use on a flexible substrate, with a resulting device efficiency of 18%. 相似文献
992.
993.
MMSE‐based transceiver design for distributed MIMO amplify‐and‐forward cooperative networks in correlated channels 下载免费PDF全文
Chia‐Chang Hu Wei‐Yu Liang Guan‐Yi Li 《International Journal of Communication Systems》2014,27(10):1686-1701
In this paper, the source‐precoder, multiple‐relay amplifying matrices, and destination‐equalizer joint optimization is investigated in distributed MIMO amplify‐and‐forward multiple‐relay networks with direct source–destination transmission in correlated fading channels. With the use of taking both the direct link and spatial correlation between antenna elements into account, the cooperative transceiver joint design is developed based on the minimum mean‐squared error criterion under individual power constraints at the source and multiple‐relay nodes. Simulation results demonstrate that the cooperative transceiver joint design architecture for an amplify‐and‐forward MIMO multiple‐relay system outperforms substantially the noncooperative transceiver design techniques on the BER performance under the spatial‐correlation channels.Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
994.
Photoinduced Proton Transfer between Photoacid and pH‐Sensitive Dyes: Influence Factors and Application for Visible‐Light‐Responsive Rewritable Paper 下载免费PDF全文
Ting Zhang Lan Sheng Junning Liu Le Ju Jianhua Li Zhen Du Weiran Zhang Minjie Li Sean Xiao‐An Zhang 《Advanced functional materials》2018,28(16)
Ink‐free printing based on rewritable paper is an efficient and environmental friendly way to reuse paper, protect resources, and save energy for sustainable development of human society. Among various kinds of rewritable media, light responsive rewritable paper (LRP) is one of the most popular research areas due to its clean and favorable noncontact writing. Visible light is more suitable for LRP for its superior penetration and much less damages to organic molecules than UV light. However, visible‐light‐responsive rewritable paper (VLRP) has only limited successes so far. Herein, a VLRP is newly designed and fabricated based on photoinduced proton transfer (PPT) between photoacid and pH‐sensitive dyes. Success of it is highly benefited from systematical investigation and in‐depth understanding on the key influence factors, such as concentration‐induced undesired isomerization, temperature, humidity, and light intensity, on the PPT and its inverse process. As‐prepared VLRP shows long‐awaited properties, such as, high color contrast and resolution, appropriate legible time of prints, excellent reversibility (>100 cycles), easiness to achieve multicolor prints, and agreeing well with environmental concept of green printing. In addition, study of influence factors on PPT in this work, to some extent, may also help people understand complex photocycle process in biosystem. 相似文献
995.
Functionalized Natural Particles: Light‐Induced Surface Modification of Natural Plant Microparticles: Toward Colloidal Science and Cellular Adhesion Applications (Adv. Funct. Mater. 18/2018) 下载免费PDF全文
996.
Antonio Sánchez‐Díaz Marta Izquierdo Salvatore Filippone Nazario Martin Emilio Palomares 《Advanced functional materials》2010,20(16):2695-2700
Organic solar cells made using a blend of DPM12 and P3HT are studied. The results show that higher Voc can be obtained when using DPM12 in comparison to the usual mono‐substituted PCBM electron acceptor. Moreover, better device performances are also registered when the cells are irradiated with sun‐simulated light of 10–50 mW cm?2 intensity. Electrochemical and time‐resolved spectroscopic measurements are compared for both devices and a 100‐mV shift in the density of states (DOS) is observed for DPM12/P3HT devices with respect to PCBM/P3HT solar cells and slow polaron‐recombination dynamics are found for the DPM12/P3HT devices. These observations can be directly correlated with the observed increase in Voc, which is in contrast with previous results that correlated the higher Voc with different ideality factors obtained using dark‐diode measurements. The origin for the shift in the DOS can be correlated to the crystallinity of the blend that is influenced by the properties of the included fullerene. 相似文献
997.
Functionalization of Graphene Oxide Films with Au and MoOx Nanoparticles as Efficient p‐Contact Electrodes for Inverted Planar Perovskite Solar Cells 下载免费PDF全文
Sumit S. Bhosale Efat Jokar Amir Fathi Cheng‐Min Tsai Chi‐Yung Wang Eric Wei‐Guang Diau 《Advanced functional materials》2018,28(37)
A graphene oxide (GO) film is functionalized with metal (Au) and metal‐oxide (MoOx) nanoparticles (NPs) as a hole‐extraction layer for high‐performance inverted planar‐heterojunction perovskite solar cells (PSCs). These NPs can increase the work function of GO, which is confirmed with X‐ray photoelectron spectra, Kelvin probe force microscopy, and ultraviolet photoelectron spectra measurements. The down‐shifts of work functions lead to a decreased level of potential energy and hence increased Voc of the PSC devices. Although the GO‐AuNP film shows rapid hole extraction and increased Voc, a Jsc improvement is not observed because of localization of the extracted holes inside the AuNP that leads to rapid charge recombination, which is confirmed with transient photoelectric measurements. The power conversion efficiency (PCE) of the GO‐AuNP device attains 14.6%, which is comparable with that of the GO‐based device (14.4%). In contrast, the rapid hole extraction from perovskite to the GO‐MoOx layer does not cause trapping of holes and delocalization of holes in the GO film accelerates rapid charge transfer to the indium tin oxide substrate; charge recombination in the perovskite/GO‐MoOx interface is hence significantly retarded. The GO‐MoOx device consequently shows significantly enhanced Voc and Jsc, for which its device performance attains PCE of 16.7% with great reproducibility and enduring stability. 相似文献
998.
本文基于多光谱遥感图像,提出了一种融合光谱特征和空间信息的主溜特征提取方法.将遥感影像的两大表现形式--光谱和空间信息结合,利用像元及其邻域的关系来描述其空间结构,用方向线来描述黄河主溜,从而确定其位置和走向.实验结果表明,该方法可有效地提取出黄河主溜特征. 相似文献
999.
1000.
Tong Jiang Yi‐Fei Zhu Jun‐Cheng Zhang Jiajie Zhu Min Zhang Jianrong Qiu 《Advanced functional materials》2019,29(51)
Visually readable codes play a crucial role in anticounterfeiting measures. However, current coding approaches do not enable time‐dependent codes to be visually read, adjusted, and differentiated in bright and dark fields. Here, using a combined strategy of piezoelectric lattice selection, oxygen vacancy engineering, and activator doping, a lanthanide ion‐doped titanate is developed that integrates mechano‐, thermo‐, and photo‐responsive color change (>18 h for bright field), persistent luminescence (>6 h for dark field), and stimulus‐triggered multimodal luminescence. The feasibility of optical encoding, visual displaying, and stimulus‐responsive encrypting of time‐dependent, dual‐field information by using the developed material is demonstrated. In particular, the differentiated display of dual‐field modes is achieved by combining mechanostimulated abolition of only the persistent luminescence and thermo‐ and photostimulated reversal of both the color change and persistent luminescence. The results provide new insights for designing advanced materials and encryption technologies for photonic displays, information security, and intelligent anticounterfeiting. 相似文献