Poly(3,4-ethylenedioxythiophene) (PEDOT) is an excellent hole-conducting polymer able to replace the liquid I(-)/I3(-) redox electrolyte in dye-sensitized solar cells (DSCs). In this work we applied the in situ photoelectropolymerization technique to synthesize PEDOT and carried out a careful analysis of the effect of different doping anions on overall solar cell performance. The anions analyzed in this work are ClO4(-), CF3SO3(-), BF4(-), and TFSI(-). The best solar cell performance was observed when the TFSI(-) anion was used. Photoelectrochemical and impedance studies reveal that the doped anions in the PEDOT hole conductor system have great influences on I-V curves, conductivity, and impedance. The optimization of these parameters allowed us to obtain an iodine-free solid-state DSC with a maximum J(sc) of 5.3 mA/cm2, V(oc) of 750 mV, and a conversion efficiency of 2.85% which is the highest efficiency obtained so far for an iodine-free solid-state DSC using PEDOT as hole-transport material.

CH3NH3PbI3 is deposited as a light absorber on a mesoporous TiO2 film and the structure and morphology are investigated at different table temperatures and with various amounts of added CH3NH3Cl. The optimized device exhibits the highest power conversion efficiency of 12.3% with an average value of 11.2%.

Tin-based halide perovskite materials have been successfully employed in lead-free perovskite solar cells,b ut the overall power conversion efficiencies (PCEs) have been limited by the high carrier concentration from the facile oxidation of Sn 2+ to Sn 4+ .N ow ac hemical route is developed for fabrication of high-quality methylammonium tin iodide perovskite (MASnI 3 )f ilms:h ydrazinium tin iodide (HASnI 3 ) perovskite film is first solution-deposited using presursors hydrazinium iodide (HAI) and tin iodide (SnI 2 ), and then transformed into MASnI 3 via acation displacement approach. With the two-step process,adense and uniform MASnI 3 film is obtained with large grain sizes and high crystallization. Detrimental oxidation is suppressed by the hydrazine released from the film during the transformation. With the MASnI 3 as light harvester,m esoporous perovskite solar cells were prepared, and amaximum power conversion efficiency (PCE) of 7.13 %i sdelivered with good reproducibility.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.