Hyperbranched conjugated polyelectrolyte bilayers for solar-cell applications

Cationically and anionically charged hyperbranched conjugated polyelectrolytes (HB-CPEs) PNMe3+ and PSO3- have been synthesized via the Heck coupling method using A(3) + B-2 type approach. Both HB-CPEs are highly fluorescent and soluble in polar organic solvents allowing processing to electrostatic adsorption. TiO2 hybrid solar cells have been fabricated with the HB-CPEs as sensitizers. The self-assembled bilayer HB-CPE films show higher overall efficiencies when compared to their respective monolayers