Guest Speaker: Prof. ZHU Jia
School of Sustainable Energy and Resources
Nanjing University
Prof. Zhu Jia is a faculty member at Nanjing University, the founding dean of School of Sustainable Energy and Resources (SSER), awardee of the National Natural Science Funds for Distinguished Young Scholar, fellow of Optica and fellow of Royal Society of Chemistry.
He received his B.S. in physics from Nanjing University in China, and his M.S. and Ph.D. in electrical engineering from Stanford University, respectively. He went on to work as a postdoctoral scholar at the University of California, Berkeley. As a Highly Cited Researcher of Clarivate, he has published over 160 papers, with over 30,000 citations, on prestigious journals such as Nature, Science, Nature series, National Science Review, Joule, Advanced Materials. He also serves as the executive editor of Nanophotonics and the editorial board member of Advanced Photonics and National Science Review.
Recent honors include: The Xplorer Prize, Tan Kah Kee Young Scientist Award, MIT Technology Review Innovators Under 35.
Abstract
Light and heat are the two most common and widely used energy in the society. Manipulating the flow of light and heat through hierarchical designs enable novel devices and functionalities in an unconventional manner. In this talk, I will present two examples.
The first example is about passive cooling. Radiative cooling which sends heat to space through atmospheric transparency window without any energy consumption, is attracting significant attention. For radiative cooling to achieve high cooling performance, it is ideal to have a selective emitter, with an emissivity dominant in the atmospheric transparency window. However, so far scalable production of radiative cooling materials with selective emissivity has not been realized. Here I will present a hierarchical design for a selective thermal emitter to achieve high performing all-day radiative cooling. Moreover, it is revealed that this hierarchically designed selective thermal emitter shows significant advantage if being applied to alleviate Global Warming or to regulate temperature of the Earth-like planet.
The second example is about interfacial solar evaporation. We report that efficient and broad-band plasmonic absorber can be fabricated through a three-dimensional self-assembly process. Because of its efficient light absorption and strong field enhancement, it can enable very efficient (>90%) solar vapor generations. Inspired by the transpiration process in plants, we report an artificial transpiration device with a unique design of two-dimensional water path. The energy transfer efficiency of this artificial transpiration device is independent of water quantity, therefore representing the signature of “interfacial evaporation”, also significantly improve the scalability and feasibility. At the end, we would like to demonstrate that this type of interfacial solar vapor generations can have direct implications in various fields such as solar desalination, zero liquid discharge, sterilization and power generations.
