Bobby Sebo

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.

Highly Uniform, Bifunctional Core/Double‐Shell‐Structured β‐NaYF4:Er3+, Yb3+ @ SiO2@TiO2 Hexagonal Sub‐microprisms for High‐Performance Dye Sensitized Solar Cells

Highly uniform core/double-shell-structured β-NaYF4:Er(3+),Yb(3+)@SiO2@TiO2 hexagonal sub-microprisms are prepared and employed in dye-sensitized solar cells (DSCs) internally. This work paves a facile way to enable the most-efficient upconversion material (β-NaYF4:Er(3+),Yb(3+)) to be used as scattering and upconversion centers in the photoelectrode of a DSC.

Microstructure, electrical and magnetic properties of Ce-doped BiFeO3 thin films

Bi1−xCexFeO3 (x=0, 0.05, 0.1, 0.15, and 0.20) (BCFO) thin films were deposited on Pt/TiN/Si3N4/Si and fluorine-doped SnO2 glass substrates by sol-gel technique, respectively. The effect of Ce doping on the microstructure, electrical and magnetic properties of BCFO films was studied. Compared to counterparts of BiFeO3 (BFO) film, the fitted Bi 4f7/2, Bi 4f5/2, Fe 2p3/2, Fe 2p1/2, and O 1s peaks for Bi0.8Ce0.2FeO3 film shift toward higher binding energy regions by amounts of 0.33, 0.29, 0.43, 0.58, and 0.49 eV, respectively. Raman redshifts of 2–4 cm−1 and shorter phonon lifetimes for the Bi0.8Ce0.2FeO3 film might be related to anharmonic interactions among Bi–O, Ce–O, (Bi, Ce)–O, and Fe–O bonds in the distorted oxygen octahedron. Compared to the pure counterparts, the dielectric and ferroelectric properties of the Bi0.8Ce0.2FeO3 film are improved due to the decreased oxygen vacancies by the stabilized oxygen octahedron. Current density values for the BFO and Bi0.8Ce0.2FeO3 film capacitors are 9.89×10−4 and...

Self-assembled free-standing polypyrrole nanotube membrane as an efficient FTO- and Pt-free counter electrode for dye-sensitized solar cells.

The construction of nanoporous conductive polymer membranes has potential applications in catalysts and energy-conversion devices. In this letter, we present a facile method to prepare free-standing polypyrrole (PPy) nanotube films by simply heating pulp-like homogeneous suspensions at a low temperature, which can be employed as a novel counter electrode (CE) to substitute for the expensive fluorine-doped tin oxide (FTO) glass and Pt used in dye-sensitized solar cells (DSSCs). The DSSCs assembled with these paper-like PPy membranes show an impressive conversion efficiency of 5.27%, which is about 84% of the cell with a conventional Pt/FTO CE (6.25%).

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.