We have synthesized water-soluble polymer, poly[(9,9-bis((6'-(N,N,N-trimethylammonium)hexyl)-2,7-fluorene))-alt-bisphenylfumaronitrile]dibromide (AHF-alt-PFN), the polymer typically obtained by the Suzuki type of polymerization reaction and shows good solubility in methanol. Bulk heterojunction polymer solar cells (BHJ-PSCs) fabricated by using water soluble conjugated polymer and positive (Cs+) and negative (F-, CO2-(3)) charge ions doping as an interfacial layer for poly(3-hexylthiophene):phenyl-C61 butyric acid methyl ester (P3HT:PCBM). We have achieved an enhancement of the short circuit density and power conversion efficiency in solar cell by introducing poly(AHF-alt-PFN) layer between the active layer and the cathode metal. The device with poly(AHF-alt-PRN) layer containing F-, CO2-(3) showed a short circuit current density more 1.3, 2.3 times higher than those of the device without poly(AHF-alt-PFN) + ion layer. We explain the better performance in solar cell with poly(AHF-alt-PFN) + ion layer was due not only to the increase of electron mobility in poly(AHF-alt-PFN) layer but also to the decrease of the electron barrier near cathode by the addition of the negative ions.

Microtubular type La0.6Sr0.4Ti0.2Fe0.8O3−δ(LSTF) membranes were prepared by electrophoretic deposition (EPD). The oxygen permeation and hydrogen production behavior of the membranes were investigated under various conditions. LSTF green layer was successfully coated onto a carbon rod and, after heat treatment at 1400°C in air, a dense LSTF tubular membrane with a thickness of 250 mm can be obtained. The oxygen permeation and hydrogen production rate were enhanced by CH4in the permeate side, and the hydrogen production rate by water splitting was 0.22 mL/min·cm2at 1000°C. It is believed that hydrogen production via water splitting using these tubular LSTF membranes is possible.