Hybrid Halide Perovskite Solar Cell Precursors: Colloidal Chemistry and Coordination Engineering behind Device Processing for High Efficiency
Top Cited Papers
- 25 March 2015
- journal article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 137 (13), 4460-4468
- https://doi.org/10.1021/jacs.5b00321
Abstract
The precursor of solution-processed perovskite thin films is one of the most central components for high-efficiency perovskite solar cells. We first present the crucial colloidal chemistry visualization of the perovskite precursor solution based on analytical spectra and reveal that perovskite precursor solutions for solar cells are generally colloidal dispersions in a mother solution, with a colloidal size up to the mesoscale, rather than real solutions. The colloid is made of a soft coordination complex in the form of a lead polyhalide framework between organic and inorganic components and can be structurally tuned by the coordination degree, thereby primarily determining the basic film coverage and morphology of deposited thin films. By utilizing coordination engineering, particularly through employing additional methylammonium halide over the stoichiometric ratio for tuning the coordination degree and mode in the initial colloidal solution, along with a thermal leaching for the selective release of excess methylammonium halides, we achieved full and even coverage, the preferential orientation, and high purity of planar perovskite thin films. We have also identified that excess organic component can reduce the colloidal size of and tune the morphology of the coordination framework in relation to final perovskite grains and partial chlorine substitution can accelerate the crystalline nucleation process of perovskite. This work demonstrates the important fundamental chemistry of perovskite precursors and provides genuine guidelines for accurately controlling the high quality of hybrid perovskite thin films without any impurity, thereby delivering efficient planar perovskite solar cells with a power conversion efficiency as high as 17% without distinct hysteresis owing to the high quality of perovskite thin films.Keywords
Funding Information
- Research Grants Council, University Grants Committee, Hong Kong (HKUST 605710, HKUST 606551, T23-407/13-N)
- Innovation and Technology Commmission (ITS/004/14)
- Chinese University of Hong Kong
This publication has 47 references indexed in Scilit:
- Inkjet Printing and Instant Chemical Transformation of a CH3NH3PbI3/Nanocarbon Electrode and Interface for Planar Perovskite Solar CellsAngewandte Chemie, 2014
- Cost-efficient clamping solar cells using candle soot for hole extraction from ambipolar perovskitesEnergy & Environmental Science, 2014
- o-Methoxy Substituents in Spiro-OMeTAD for Efficient Inorganic–Organic Hybrid Perovskite Solar CellsJournal of the American Chemical Society, 2014
- Elucidating the charge carrier separation and working mechanism of CH3NH3PbI3−xClx perovskite solar cellsNature Communications, 2014
- Efficient planar heterojunction perovskite solar cells by vapour depositionNature, 2013
- Sequential deposition as a route to high-performance perovskite-sensitized solar cellsNature, 2013
- Low-temperature processed meso-superstructured to thin-film perovskite solar cellsEnergy & Environmental Science, 2013
- All-solid-state hybrid solar cells based on a new organometal halide perovskite sensitizer and one-dimensional TiO2 nanowire arraysNanoscale, 2013
- Efficient Hybrid Solar Cells Based on Meso-Superstructured Organometal Halide PerovskitesScience, 2012
- Lead Iodide Perovskite Sensitized All-Solid-State Submicron Thin Film Mesoscopic Solar Cell with Efficiency Exceeding 9%Scientific Reports, 2012