Layered Double Hydroxides as an Effective Additive in Polymer Gelled Electrolyte based Dye-Sensitized Solar Cells

Layered double hydroxides (LDH), a class of anionic clay materials, were developed as an effective additive for polymer gelled electrolytes for use in dye-sensitized solar cells (DSSC). Carbonate and chloride intercalated Zn-Al LDHs, ZnAl-CO₃ LDH, and ZnAl-Cl LDH were prepared with coprecipitation methods. The addition of the two LDHs significantly improved, in terms of power conversion efficiency (PCE), over the plain poly­(vinylidene fluoride-<i>co</i>-hexafluoropropylene) (PVDF-HFP) gelled electrolyte and competed favorably with the liquid electrolyte based DSSCs, 8.13% for the liquid electrolyte, 7.48% for the plain PVDF-HFP gelled electrolyte, 8.11% for the ZnAl-CO₃ LDH/PVDF-HFP gelled electrolyte, and 8.00% for the ZnAl-Cl LDH/PVDF-HFP gelled electrolyte based DSSCs. The good performance in PCEs achieved by the LDH-loaded DSSCs came mainly from the significant boost in open circuit voltages (<i>V</i>_oc), from 0.74 V for both the liquid electrolyte and PVDF-HFP gelled electrolyte based DSSCs to 0.79 V for both the ZnAl-CO₃ LDH/PVDF-HFP and ZnAl-Cl LDH/PVDF-HFP gelled electrolyte based DSSCs. The boost in <i>V</i>_oc was contributed mainly by the positive shift in redox potential of the redox couple, I^–/I₃^–, as revealed from cyclic voltammetry analyses. As for the long-term stability, PCE retention rates of 96 and 99% after 504 h were achieved by the ZnAl-CO₃ LDH/PVDF-HFP and ZnAl-Cl LDH/PVDF-HFP gelled electrolyte based DSSCs, respectively, appreciably better than 92% achieved by the liquid electrolyte based one after 480 h

Associations of child’s use of mobile devices and parent–child shared reading with the emotional and behavioral problems among children with mothers with a low depression level—results from multiple linear regression models.

Associations of child’s use of mobile devices and parent–child shared reading with the emotional and behavioral problems among children with mothers with a low depression level—results from multiple linear regression models.</p

Associations of general traits and maternal use of mobile devices with child’s exceeding the recommended use of mobile devices—results from multiple logistic regression models (n = 202).

Associations of general traits and maternal use of mobile devices with child’s exceeding the recommended use of mobile devices—results from multiple logistic regression models (n = 202).</p

Associations of child’s use of mobile devices and parent–child shared reading with the emotional and behavioral problems among children with mothers with a high depression level—results from multiple linear regression models.

Associations of child’s use of mobile devices and parent–child shared reading with the emotional and behavioral problems among children with mothers with a high depression level—results from multiple linear regression models.</p

Child’s daily use of mobile devices according to general characteristics of participants (n = 202).

Child’s daily use of mobile devices according to general characteristics of participants (n = 202).</p