Letian Dou Group

We welcome Dr. Sung-Doo Baek, a research professor from Department of Materials Science and Engineering of Yonsei University, visiting us for 6 months. Dr. Baek is an expert on perovskite LEDs. Welcome to the group and look forward to working together!

Dharini passes her PhD qualifier exam. Congratulations!

We welcome Wonryeol Yang, a second year PhD student from POSTECH (Prof. Yong-Young Noh group), visiting us for 3 months. Wonryeol is an expert on perovskite FETs. Welcome to the group and look forward to working together!

Zitang (Tim) received best oral presentation award in the 31st Annual ChE Graduate Student Organization (GSO) Symposium for his work in topochemical polymerization and sustainable polymers. Congratulations!

Xuyi, Zitang, and Bumjoon’s work on recyclable polymers featuring topochemically elongated and weakened carbon–carbon bonds has been published in JACS! Big congratulations!

We demonstrate a topochemical approach for creating elongated C–C bonds with a bond length of 1.57∼1.63 Å between repeating units with decreased bond dissociation energies. These materials exhibit rapid depolymerization via breakage of the elongated bond within a desirable temperature range (140∼260 °C) while otherwise remaining remarkably stable under harsh conditions. The topochemically prepared polymers are processable and 3D-printable while maintaining a high depolymerization yield and tunable mechanical properties. These results suggest that the crystalline polymers synthesized from simple photochemistry and without expensive catalysts are promising for practical applications with complete materials’ circularity. Read the paper here. Read a Blog on Medium here.

Aidan’s paper entitled “Controlling Crystallization of Quasi-2D Perovskite Solar Cells: Incorporating Bulky Conjugated Ligands” has been published in Advanced Energy Materials. Congratulations!

A bulky bi-thiophene 2T ligand is used to create vertically-aligned quasi-2D perovskite films. By starting with a poorly coordinating solvent (GBL) and adding a small amount of DMSO and methanol, it is found that vertical orientation and z-uniformity is greatly improved. These are examined using grazing-incidence wide-angle X-ray scattering and advanced optical characterizations. Solar cells with an max efficiency of 13.3% are demonstrated. The quasi-2D absorbing layers show excellent stability in moisture, remaining unchanged after hundreds of hours. Read the story here.

Undergrad visiting students Xinan Wu and Peiran Niu, both from Peking University Physics Department, joined the group. Xinan will work on OSiP LEDs and Peiran will work on large area solar cells. Welcome to the group and look forward to working together!

The groups receives Ralph W. and Grace M. Showalter Research Trust award to support our polymer single crystal and sustainable polymer work. Thank you for the generous support! Congratulations to the group!

The group warmly welcomes two new postdoc fellows Dr. Wenhao Shao and Dr. Xuyi Luo joining us. Wenhao received his PhD in Chemistry from University of Michigan with Prof. Jinsang Kim. Wenhao will work on synthesis and applications of novel OSiPs. Xuyi received his PhD in Chemistry from Purdue University with Prof. Jianguo Mei. He actually has been working with us for a year before receiving his PhD and he will continue working with us on polymer single crystals and sustainable polymers for another year. Welcome both to the group. Look forward to working together!

Blake Finkenauer successfully defended his thesis today! — Third PhD in our group. Big congratulations! Blake is heading to First Solar in California as a process engineer to develop perovskite solar modules toward commercialization. Best of luck in your future endeavors! Look forward to seeing the products!