Enhanced Charge Carrier Transport and Device Performance Through Dual-Cesium Doping in Mixed-Cation Perovskite Solar Cells with Near Unity Free Carrier Ratios.

PbI-enriched mixed perovskite film [FAMAPb(IBr)] has been widely studied due to its great potential in perovskite solar cell (PSC) applications. Herein, a FAMAPb(IBr) film has been fabricated with the temperature-dependent optical absorption spectra utilized to determine its exciton binding energy. A ∼13 meV exciton binding energy is estimated, and a near-unity fraction of free carriers out of the total photoexcitons has been obtained in the solar cell operating regime at equilibrium state.

Electrosprayed TiO nanoporous hemispheres for enhanced electron transport and device performance of formamidinium based perovskite solar cells.

Titanium dioxide (TiO) nanoporous hemispheres (NHSs) with a radius of ∼200 nm are fabricated by electrospraying a hydrothermally synthesized TiO nanoparticle (NP) suspension solution. The resulting TiO NHSs are highly porous, which are beneficial to the infiltration of perovskites and provide a larger contact area, as building blocks to construct a mesoporous TiO layer for FAMAPb(IBr) based perovskite solar cells (PSCs). By varying the TiO NHS collecting period (15 s, 30 s, 60 s and 90 s) during the electrospraying process, the performance of PSCs changes with different TiO NHS distribution densities.

Simultaneous improvements in power conversion efficiency and operational stability of polymer solar cells by interfacial engineering.

This article addresses simultaneous improvements in the photovoltaic performance and operational stability of organic photovoltaic devices (OPVs) in the inverted configuration when nanostructured ZnO characterized by a lower density of localized surface atomic energy states is employed as an electron transport layer. Two sets of devices with the configuration ITO/ZnO/P3HT:PCBM/MoO3/Ag are employed in the present study. A difference in the density of localized energy states in the band gap of ZnO was produced by altering the crystallinity by annealing the ZnO at two temperatures, viz.

Enhancing the stability of polymer solar cells by improving the conductivity of the nanostructured MoO3 hole-transport layer.

This article demonstrates improvements in the operational stability of organic solar cells (OSCs) by taking advantage of the relationship between oxygen stoichiometry and conductivity in nanostructured metal oxide semiconductors (n-MOS). OSCs in the inverted device configuration of ITO/Ca/P3HT:PCBM/MoO3/Ag were employed in the present study. A high degree of oxygen defects were introduced in the hole-conducting MoO3 layer by annealing the devices under vacuum (≥10(-5) mbar) for nominal temperature (120 °C) and time (10 min).

Random nanowires of nickel doped TiO2 with high surface area and electron mobility for high efficiency dye-sensitized solar cells.

Mesoporous TiO(2) with a large specific surface area (~150 m(2) g(-1)) is the most successful material in dye-sensitized solar cells so far; however, its inferior charge mobility is a major efficiency limiter. This paper demonstrates that random nanowires of Ni-doped TiO(2) (Ni:TiO(2)) have a dramatic influence on the particulate and charge transport properties. Nanowires (dia ~60 nm) of Ni:TiO(2) with a specific surface area of ~80 m(2) g(-1) were developed by an electrospinning technique.