The organic metal halide perovskite material is capable of high throughput manufacturing via traditional deposition processes used in roll-to-roll, yet thermal annealing post deposition may require long ovens. We report rapid annealed perovskite thin films using intense pulsed light (IPL) to initiate a radiative thermal response that is enabled by an alkyl halide additive that collectively improves the performance of a device processed in an ambient environment from a baseline of 10 to 16.5% efficiency. Previous reports on CH 3 NH 3 PbI 3 perovskite films using IPL processing achieved functional devices in milli-second time scales and are promising for high throughput manufacturing processes under ambient conditions. In this study, we found that the addition of diiodomethane (CH 2 I 2 ) as an additive to the methylammonium iodide (MAI)/lead iodide (PbI 2 ) precursor ink chemistry and subsequent IPL thermal annealing are inter-dependent. The concentration of CH 2 I 2 and IPL processing parameters have a direct effect on the surface morphology of the films and performance within a perovskite solar cell (PSC). The CH 2 I 2 dissociates under exposure to ultraviolet (UV) radiation from the IPL source liberating iodine ions in the film, influencing the perovskite formationmore »
Energy-distinguishable bipolar UV photoelectron injection from LiCl-promoted FAPbCl 3 perovskite nanorods
High-performance optoelectronic devices, such as solar cells and light-emitting diodes, have been fabricated with lead halide perovskites owing to their superior carrier properties. However, charge transport in such optoelectronics is intrinsically directional due to the existence of p–n junctions, which thus lacks the potential to elucidate any perturbations in light or electricity during energy conversion. Here, with the presence of a LiCl additive in a formamidinium chloride (FACl) solution, the as-grown LiCl:FAPbCl 3 nanorods demonstrate greatly enhanced crystallinity and UV photoresponse as compared to pristine FAPbCl 3 nanostructures without the LiCl additive. Most importantly, the LiCl:FAPbCl 3 nanorod film exhibits unprecedented distinguishability to UV photons with different energies and oscillating intensities, in the form of bipolar and periodically oscillatory photocurrents. This work could advance the fundamental understanding of photoinduced carrier processes in halide perovskites and facilitate the development of novel UV-based optical communications.
- Award ID(s):
- 1806152
- Publication Date:
- NSF-PAR ID:
- 10097251
- Journal Name:
- Journal of Materials Chemistry A
- Volume:
- 7
- Issue:
- 21
- Page Range or eLocation-ID:
- 13043 to 13049
- ISSN:
- 2050-7488
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Publisher's Version of Record
- https://doi.org/10.1039/C9TA01160A
