Semiconductor nanostructures are considered as a good perform for studying their interesting physical properties and potential applications in renewable energy harvesting and optoelectronic devices. Recently, there is a renaissance of halide perovskites as a promising class of semiconductor materials for a variety of photovoltaics and optoelectronics. This talk will focus on the new strategies for the syntheses of 1D and 2D halide perovskite nanostructures and fabrication of novel functional heterojunctions and optoelectronic devices.

Firstly, we present new synthetic methodology of halide perovskite nanowires with desired size, composition, and properties. Such synthetic approach includes colloidal, solution-phase, and vapor-phase growth. Sub-micrometer single crystal nanowires from solution-phase growth were demonstrated as efficient optical medium for high-performance and robust laser application. Due to the relatively weak bonding in halide perovskites, ions are highly dynamics inside the crystal lattice. Anion exchange was demonstrated in these 1D materials with high PLQE throughout the exchange reaction. Based on this, we demonstrate perovskite nanowire heterojunctions with high spatial resolution. The solid-solid anion exchange dynamics can be resolved in CsPbBr3-CsPbCl3 hetero-junction nanowires through a non-destructive optical method. Secondly, we will discuss our new discoveries on the synthesis of atomically thin two-dimensional halide perovskites. These new 2D structure exhibits high PLQE and tunable optical properties for optoelectronics and photonics application. Thirdly, we demonstrate phase transition solar cells based on halide perovskites that can change color under different external stimuli. Overall, halide perovskites nanomaterials offer unique opportunities for exploring fundamental research and enable nanoscale optoelectronic devices.

Dr. Dou obtained his B.S. in Chemistry from Peking University in 2009. He received his Ph.D. from the Department of Materials Science and Engineering at UCLA, in 2014.

Prior to joining Purdue University, he was a Postdoc Fellow at the University of California-Berkeley and Materials Science Division, Lawrence Berkeley National Laboratory. Dr. Dou was part of a research team that set a certified world record of 10.6% power conversion efficiency for organic solar cells. He has been awarded six patents and is the recipient of the Link Foundation Energy Fellowship (2013-2015).

Dr. Dou’s research interests include the synthesis of organic semiconductors, inorganic nanostructures, hybrid materials, and related optoelectronic properties and devices. The Dou research group is interested in hybrid materials synthesis and processing for the next generation energy harvesting and optoelectronics devices. Both fundamental understanding of the materials structure-property relationships and the application in high performance energy-efficient devices are emphasized.

Birck Nanotechnology Center

Researchers should cite this work as follows:

• Letian Dou (2018), "Semiconducting Halide Perovskite Nanomaterials and Heterojunctions," https://nanohub.org/resources/28501.

  BibTex | EndNote

1. halides
2. heterojunctions
3. nanoelectronics
4. nanophotonics
5. nanowires
6. Optoelectronic Devices
7. perovskites
8. photovoltaics (PV)
9. solar cells