Qidong Tai

In situ prepared transparent polyaniline electrode and its application in bifacial dye-sensitized solar cells.

Highly uniform and transparent polyaniline (PANI) electrodes that can be used as counter electrodes in dye-sensitized solar cells (DSSCs) were prepared by a facile in situ polymerization method. They were used to fabricate a novel bifacially active transparent DSSC, which showed conversion efficiencies of 6.54 and 4.26% corresponding to front- and rear-side illumination, respectively. Meanwhile, the efficiency of the same photoanode employing a Pt counter electrode was 6.69%. Compared to conventional Pt-based DSSCs, the design of the bifacial DSSC fabricated in this work would help to bring down the cost of energy production due to the lower cost of the materials and the higher power-generating efficiency of such devices for their capabilities of utilizing the light from both sides. These promising results highlight the potential application of PANI in cost-effective, transparent DSSCs.

Electrospun TiO2 Nanofiber‐Based Cell Capture Assay for Detecting Circulating Tumor Cells from Colorectal and Gastric Cancer Patients

A nanostructured platform that combines electrospun TiO(2) nanofibers (TiNFs)-deposited substrate and cell-capture agent realizes significant capture of circulating tumor cells (CTCs). The enhanced local topographic interactions between the horizontally packed TiNFs deposited substrates and extracellular matrix scaffolds, in addition to anti-EpCAM/EpCAM biological recognition, contributes to the significantly enhanced capture efficiency compared to flat surfaces.

Improvement in dye-sensitized solar cells with a ZnO-coated TiO2 electrode by rf magnetron sputtering

A surface modification method was carried out by rf magnetron sputtering to fabricate ZnO-coated TiO2 electrodes (TiO2∕ZnO) for improving the performance of dye-sensitized solar cells. The TiO2∕ZnO electrodes had been characterized by x-ray photoelectron spectroscopy, scanning electron microscopy, UV-visible spectrophotometer, and electrochemical impedance spectroscopy. The study results revealed that the TiO2 modification suppresses interfacial recombination. Sputtering ZnO for 3min on 5μm TiO2 greatly improves all cell parameters, resulting in increasing efficiency from 4.76% to 6.55%.A surface modification method was carried out by rf magnetron sputtering to fabricate ZnO-coated TiO2 electrodes (TiO2∕ZnO) for improving the performance of dye-sensitized solar cells. The TiO2∕ZnO electrodes had been characterized by x-ray photoelectron spectroscopy, scanning electron microscopy, UV-visible spectrophotometer, and electrochemical impedance spectroscopy. The study results revealed that the TiO2 modification suppresses interfacial recombination. Sputtering ZnO for 3min on 5μm TiO2 greatly improves all cell parameters, resulting in increasing efficiency from 4.76% to 6.55%.

Optimization of a quasi-solid-state dye-sensitized solar cell employing a nanocrystal?polymer composite electrolyte modified with water and ethanol

A quasi-solid-state dye-sensitized solar cell employing a poly(ethylene oxide)-poly(vinylidene fluoride) (PEO-PVDF)/TiO2 gel electrolyte modified by various concentrations of water and ethanol is described. It is shown that the introduction of water and ethanol prevents the crystallization of the polymer matrix, and enhances the free I(-)/I(3)(-) concentration and the networks for ion transportation in the electrolyte, thus leading to an improvement in conductivity. A high energy conversion efficiency of about 5.8% is achieved by controlling the additive concentration in the electrolyte. Optimization of the additive-modified electrolyte performance has been obtained by studying the cross-linking behavior of water and ethanol with Fourier transform infrared (FTIR), differential scanning calorimetry (DSC) and viscosity measurements, and the electrical conduction behavior of the electrolyte with impedance spectra measurements.

Facile preparation of nanofibrous polyaniline thin film as counter electrodes for dye sensitized solar cells

A fibrous polyaniline (PANI) thin film has been fabricated from prepared PANI nanofiber solution by Marangoni flow. The PANI retained its original fiber morphology after being deposited into films and formed highly interconnected network structures, which leads to an excellent electrochemical catalytic activity. This PANI thin film was applied in dye sensitized solar cell (DSSC) as counter electrode. A power conversion efficiency (PCE) of 3.8% of the DSSC by this PANI counter electrode was obtained without optimization of synthesis conditions, compared with 5.1% PCE by traditional Pt counter electrode. Better performances are attainable by improving the conductivity of PANI with acid doping process to decrease the sheet resistance of this electrode. Facile synthesis process and good performance of these nanofibrous PANI thin films highlight the potential large scale applications for low-cost counter electrode in DSSCs.

A methylene bridged bisimidazolium iodide based low-volatility electrolyte for efficient dye-sensitized solar cells

In this paper, we demonstrate that 1,1′-methylene bis(3-n-methylimidazolium) diiodide (MMIDI) can be used as an excellent alternative iodide source to conventional lithium iodide (LiI) in electrolyte for dye-sensitized solar cell (DSSC). The MMIDI is cheaper and shows much improved physical and chemical stability compared to LiI. Noticeably, smaller charge transfer resistance for the reduction of triiodide and longer electron lifetime are found in the DSSCs based on MMIDI electrolyte, which result in a 23% higher overall conversion efficiency (5.26%) than that based on LiI electrolyte (4.27%). When the initial MMIDI electrolyte is optimized with functional additives, a promising 6.24% conversion efficiency is achieved.