Le Quoc Bao

Effect of LiI/I2 concentration and photoelectrode thickness on the photovoltaic properties of NiO-based p-type dye-sensitized solar cells

ABSTRACT In this paper, we have studied the effect of LiI and I2 concentrations on the photovoltaic properties of dye-sensitized solar cells (DSSCs) based on NiO. For all concentrations of iodine, the photo-voltage (VOC) and current density (JSC) increased with increasing LiI concentration. The increment in JSC is ascribed to the higher charge transport efficiency of the device. In addition, the effect of NiO film thickness on the efficiency of the as-fabricated DSSCs was investigated, and an optimum efficiency of 0.0587% was obtained for the DSSC with a double-layer NiO film.

Improved performance of P -type DSCs with a compact blocking layer coated by different thicknesses

The introduction of different thicknesses of a compact NiO blocking layer coating with different spin speeds on FTO and followed by a coating of photoactive NiO electrode for p-type dye-sensitized solar cells (p-DSCs). This study examined the fabrication of a compact NiO blocking layer by decomposing an ethanolic precursor solution of nickel acetate tetrahydrate. The DCBZ dye used as the photosensitizer for the NiO electrode in the p-DSCs device and their performances have been analyzed. The enhancement of photovoltaic performance and resulted from an increase in the power conversion efficiency (η). The electrochemical impedance spectroscopy (EIS) measurement demonstrated that charge recombination was suppressed when a compact NiO blocking layer was applied. The results showed that the best p-DSC was achieved by employing 3000 rpm spin-coated process for different times of blocking layer.

Synthesis and investigation of triphenylamine-based double branched organic dyes for p-type dye-sensitized solar cells

ABSTRACT Two double branched organic dyes (T1I and T2I) were synthesized, characterized, and employed as photosensitizers in p-type dye-sensitized solar cells (p-DSSC); we have compared with corresponding single branched dye (TC1) and reference dye P1. The absorbance of the dyes in solution was red shifted and the oxidation potential gradually decreased with increasing the donating ability. It was found that modification from single branched (TC1) to double branched (T1I and T2I) system resulted in increased photocurrent density leading to the higher photovoltaic performances. The charge transporting ability is increased with the introduction of double branching, as evidenced from electrochemical impedance analysis.