I3 Perovskite Research Articles

Highly Efficient Perovskite Solar Cells with Substantial Reduction of Lead Content.

Despite organometal halide perovskite solar cells have recently exhibited a significant leap in efficiency, the Sn-based perovskite solar cells still suffer from low efficiency. Here, a series homogeneous CH3NH3Pb(1−x)SnxI3 (0 ≤ x ≤ 1) perovskite thin films with full coverage were obtained via solvent engineering. In particular, the intermediate complexes of PbI2/(SnI2)∙(DMSO)x were proved to retard the crystallization of CH3NH3SnI3, thus allowing the realization of high quality Sn-introduced perovskite thin films. The external quantum efficiency (EQE) of as-prepared solar cells were demonstrated to extend a broad absorption minimum over 50% in the wavelength range from 350 to 950 nm accompanied by a noteworthy absorption onset up to 1050 nm. The CH3NH3Pb0.75Sn0.25I3 perovskite solar cells with inverted structure were consequently realized with maximum power conversion efficiency (PCE) of 14.12%.

Regulatory band gap of vacancy at the B sites in CH3NH3Pb1−xI3 perovskite

The structure, electronic structure, states density and optics properties of the orthorhombic CH3NH3Pb[Formula: see text]I3 perovskite with vacancy at the B sites are calculated by the CASTEP program. The calculated results indicate that the cell volume shrinks with the content of vacancy at the B sites increasing, and the structure has the large degree of distortion from the cubic structure. The band gaps are 1.656, 1.750, 3.077, 3.256 and 4.76 eV, corresponding to [Formula: see text], 0.25, 0.50, 0.75 and 1.00, respectively. As an application, the additional absorption peak can be obtained by CH3NH3Pb[Formula: see text]I3 perovskite doped vacancy at the B sites.

Stable Low-Bandgap Pb-Sn Binary Perovskites for Tandem Solar Cells.

A low-bandgap (1.33 eV) Sn-based MA0.5 FA0.5 Pb0.75 Sn0.25 I3 perovskite is developed via combined compositional, process, and interfacial engineering. It can deliver a high power conversion efficiency (PCE) of 14.19%. Finally, a four-terminal all-perovskite tandem solar cell is demonstrated by combining this low-bandgap cell with a semitransparent MAPbI3 cell to achieve a high efficiency of 19.08%.

Alternative, Lead-free, Hybrid Organic–Inorganic Perovskites for Solar Applications: A DFT Analysis

Abstract We here theoretically investigate, by means of a density functional-based approach, the MATl0.5Bi0.5I3 (MA: CH3NH3+) perovskite, where Tl/Bi aliovalent ionic pairs replace Pb cations of the parental MAPbI3. On the basis of a pure structural and electronic analysis, considering the close similarities with the well-assessed MAPbI3 system, we predict such compounds as potential alternative materials for solar applications.

CH3NH3SnxPb(1-x)I3 Perovskite Solar Cells Covering up to 1060 nm.

We report photovoltaic performances of all-solid state Sn/Pb halide-based perovskite solar cells. The cell has the following composition: F-doped SnO2 layered glass/compact titania layer/porous titania layer/CH3NH3SnxPb(1-x)I3/regioregular poly(3-hexylthiophene-2,5-diyl). Sn halide perovskite itself did not show photovoltaic properties. Photovoltaic properties were observed when PbI2 was added in SnI2. The best performance was obtained by using CH3NH3Sn0.5Pb0.5I3 perovskite. 4.18% efficiency with open circuit voltage 0.42 V, fill factor 0.50, and short circuit current 20.04 mA/cm(2) are reported. The edge of the incident photon to current efficiency curve reached 1060 nm, which was 260 nm red-shifted compared with that of CH3NH3PbI3 perovskite solar cells.