Colloidal PbS and PbSeS Quantum Dot Sensitized Solar Cells Prepared by Electrophoretic Deposition

Here we report the developement of quantum dot sensitized solar cells (QDSCs) using colloidal PbS and PbSeS QDs and polysulfide electrolyte for high photocurrents. QDSCs have been prepared in a novel sensitizing way employing electrophoretic deposition (EPD), and protecting the colloidal QDs from corrosive electrolyte with a CdS coating. EPD allows a rapid, uniform and effective sensitization with QDs, while the CdS coating stabilizes the electrode. The effect of electrophoretic deposition time and of colloidal QD size on cell efficiency is analyzed. Efficiencies as high as 2.1±0.2% are reported

Ind. Eng. Chem. Res.

This work describes a self-consistent unified chemical model for calculating the solubility of CaSO4 phases in the H + Na + Ca+ Mg + Al + Fe(II) + Cl + SO4+ H2O system from low to high solution concentration within the temperature range of 298-353 K. The model was built with the aid of OLI Systems platform via the regression of new solubility data of calcium sulfate dihydrate in HCl or HCl + CaCl2 aqueous solutions containing various metal chloride salts, such as NaCl, MgCl2, FeCl2, and AlCl3. Via this regression analysis, new Bromley-Zemaitis activity coefficient model parameters and empirical dissociation constant parameters were determined for many ion pairs consisting of cations (Na+, Mg2+ Fe2+, and Al3+) and anions (SO42-) as well as for the species MgSO4(aq), AlSO4+, and Al(SO4)(2)(-). The new model was HSO4-, and Al(SO4)(2)(-)) shown to successfully predict the solubility of calcium sulfate phases in multicomponent systems not used in model parametrization. The new model is used to explain the complex effect metal chlorides have on the solubility of CaSO4 phases on the basis of governing metal-sulfate speciation equilibria.This work describes a self-consistent unified chemical model for calculating the solubility of CaSO4 phases in the H + Na + Ca+ Mg + Al + Fe(II) + Cl + SO4+ H2O system from low to high solution concentration within the temperature range of 298-353 K. The model was built with the aid of OLI Systems platform via the regression of new solubility data of calcium sulfate dihydrate in HCl or HCl + CaCl2 aqueous solutions containing various metal chloride salts, such as NaCl, MgCl2, FeCl2, and AlCl3. Via this regression analysis, new Bromley-Zemaitis activity coefficient model parameters and empirical dissociation constant parameters were determined for many ion pairs consisting of cations (Na+, Mg2+ Fe2+, and Al3+) and anions (SO42-) as well as for the species MgSO4(aq), AlSO4+, and Al(SO4)(2)(-). The new model was HSO4-, and Al(SO4)(2)(-)) shown to successfully predict the solubility of calcium sulfate phases in multicomponent systems not used in model parametrization. The new model is used to explain the complex effect metal chlorides have on the solubility of CaSO4 phases on the basis of governing metal-sulfate speciation equilibria