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A series of new organic D−π−A dyes, coded as DS-1, DS-2, DS-3, and DS-4, was designed, synthesized, and characterized by 1H NMR,13C NMR, infrared spectroscopy, mass spectrometry, and elemental analysis. These dyes consist of a di(p-tolyl)phenylamine moiety as an electron donor, a cyanoacetic acid moiety as an electron acceptor/anchoring group, and different types of conducting thiophene units as electron spacers to bridge the donor and acceptor. It was found that both the use of di(p-tolyl)phenylamine donor and the variation of electron spacers in the D−π−A dyes played an essential role in modifying and/or tuning physical properties of organic dyes. These dyes were developed as sensitizers for the application in dye-sensitized TiO2 nanocrystalline solar cells (DSSCs), and their photophysical and electrochemical properties were investigated. The DSSCs based on the dyes gave good performance in terms of incident photon-to-current conversion efficiency (IPCE) in the range of 400−700 nm. A solar-energy-to-electricity conversion efficiency (η) of 7.00% was obtained with the DSSC based on 5-[[2-[p-(di-p-tolylamino)]styryl]thiophene-yl]thiophene-2-cyanoacrylic acid (DS-2) under simulated AM 1.5 G irradiation (100 mW/cm2): short-circuit current density (J sc) of 15.3 mA cm−2; open-circuit voltage (V oc) of 0.633 V; fill factor (FF) of 0.725. The density functional theory (DFT) calculation suggests that the electron-transfer distribution moves from the donor unit to the acceptor under light irradiation, which means efficient intramolecular charge transfer.

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The surface defects of the organometallic perovskite play an important role in the photovoltaic performance of solar cells, which depress the conversion efficiency and cause photocurrent hysteresis.

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The rate‐determining process for electrochemical energy storage is largely determined by ion transport occurring in the electrode materials. Apart from decreasing the distance of ion diffusion, the enhancement of ionic mobility is crucial for ion transport. Here, a localized electron enhanced ion transport mechanism to promote ion mobility for ultrafast energy storage is proposed. Theoretical calculations and analysis reveal that highly localized electrons can be induced by intrinsic defects, and the migration barrier of ions can be obviously reduced. Consistently, experiment results reveal that this mechanism leads to an enhancement of Li/Na ion diffusivity by two orders of magnitude. At high mass loading of 10 mg cm−2 and high rate of 10C, a reversible energy storage capacity up to 190 mAh g−1 is achieved, which is ten times greater than achievable by commercial crystals with comparable dimensions.

Large-area Ag nanowires are ordered by spontaneous spreading of volatile droplet on a wettable solid surface. Compared with other nanowires orientation methods, radial shaped oriented Ag nanowires in a large ring region are obtained in an extremely short time. Furthermore, the radial shaped oriented Ag nanowires are transferred and aligned into one direction. Based on the hydrodynamics, the coactions among the microfluid, gravity effect and the adhesion of substrate on the orientation of the Ag nanowires are clearly revealed. This spreading method opens an efficient way for extreme economic, efficient and “green” way for commercial producing ordered nanowire arrays.