CUI Yi, world famous scientist innanotechnology and professor of Department of Material Science and Engineering, Stanford University,came to Yanqihu Campus of University of Chinese Academy of Sciences (UCAS) to deliver a speech at the Yanqihu Eminent Speakers Lecture Series entitled “Nanotechnology for Energy and Environment” recently, and exchanged ideas with the audience on topics about environment, energy and future technology.
Prof. CUIis delivering an excellent report
Prof. Y.Cui firstly reviewed the development of clean energy internationally during the past decade, and pointed the decline in solar power generation cost and the widespread availability of electric vehicles remained the two key advancements in the application of clean energy in industrial development, which marksa coming economic era led by electric energy. In the past ten years, Prof. CUIhas been constantly focused on new material designs and applied these scientific achievements to energy and environment spheres.
In his speech, Prof. CUI shared hiswork of designing high-energy lithium-sulfur batteries with students present. The design and generation of high energy lithium battery requires further researches probing problems arising in current battery system. Through the comparison between merits and demerits of a series of positive and negative electrode materials, Prof. Y.Cui and his team members initially put forward the solution to the problem of volume expansion of silicon-based materials which can be improved by using silicon nanowires as negative electrons, and used the in-situ electron microscopy to study the attenuation mechanism of the negative electrode of silicon material and the structural changes of the nanowire during charge and discharge. Via the upgrade of nanostructure, the team suggested the interface problem of silicon-based anode and achieved remarkable breakthroughs in the field. Hence after, Pros. Y.Cui led his team successfully conducted and updated silicon-based anode gradually applied to industry.
Prof. Y. Cui asked a question “what should we do after the silicon “after the success of silicon-based anode. He pointed that if we want to make the density of the battery reach 500 wh/kg, we must develop lithium-metal battery. The serious dendrite problem of lithium hinders the absolute security of lithium-metal battery which makes the problem be a universally worldwide issue. Prof. added lithium dendrite ingrains its own high reactivity and large volume change. Therefore the team got started at electrode interface research, added a framework to lithium negative electrode, and directional control of lithium-metal deposition sites thus greatly avoiding lithium dendrite issue. The outstanding performance of Prof. Y. Cui and the team has promoted the development of lithium-metal battery and the industrialization of lithium-metal anode.
Report meeting situation
Next, Prof. Y. Cui suggested material and technology deserved equal importance and attention, as premium materials and sophisticated technologies were co-related with each other and the latter is contributed to the introduction of the design and the development of the materials. Prof. Y. Cui took advantage of in-situ gas environment electron microscopy to study the processing of lithium surface witch has an instructive meaning to lithium stability and its commercialization. In 2017, Prof. Y. Cui initially introduced cryo-electron microscopy into the study of lithium-metal and SEI membrane mechanism, obtained the atomic images of lithium-metal for the first time in the international stage and enhanced the scientific researches on the micro-interface of lithium-metal electrodes. The scientific practice is with crucial significance. Thanks to the sensitivity to scientific research, Prof. Y. Cui’s researches are at the forefront of technology and lead the trend of technology.
Prof. Y. Cui also introduced the application of new nanomaterials in life. People wearing clothes made by a sort of wearable nano-polyethylene fabric will feel they carry an air conditioner adjusting temperature and thus reducing energy consumption of the machine. Additionally, Pros. Y. Cui introduced outstanding contributions of his team in nanomaterial in purifying water, nanomaterials in fighting smog and etc. The industrialization worth and meaning of these research results lay in theiravailability to solve problems in reality.
By ZHANG Liyun