報告時間：2019年5月7日（周二）9:30-10:30
報告地點：北辰校區材料樓517
報告題目: High-Resolution Visualization of the Redox Activity of Li2O2 in Non-Aqueous Media: Conformal Layer VS. Toroid Structure
報告內容: A strong relationship between the surface structure and the redox activity of the Li2O2 is visualized directly using a scanning electrochemical cell microscopy, byemploying a dual-barrel nanopipette containing a unique gel polymer electrolyte. These measurements reveal considerable local heterogeneity with significantly enhanced electrochemical activity at toroidal Li2O2 structures when compared to the conformal layer that is usually formed on the cathode of Li–O2 batteries.
報告人簡介：
Dr. Pei San E，女，英國華威大學制造工程系研究員。2017年畢業于英國華威大學，獲得理學博士學位。從2011年至今，先后在Fuji Electric公司擔任工程師、在英國劍橋大學任職副研究員、以及在英國華威大學擔任研究員等職務。迄今獲得過馬來西亞國家科研創新獎、英國創新展金獎、英國最佳創新獎、馬來西亞可持續發展創新獎等獎項。目前主要從事于基礎電化學、納米電化學、生物電化學、氣體傳感器以及鋰離子電池等方面的研究工作，且在國際著名期刊包括ACS Applied Mater. Inter.,ElectrochimicaActa, J. Phys. Chem. C, PCCP等國際期刊上發表SCI論文多篇，并20余次被邀請在國際重要會議做學術報告。
報告時間：2019年5月7日（周二）10:30-11:30
報告地點：北辰校區材料樓517
報告題目: Non-Aqueous Electrodeposition of Functional Materials
報告內容: Thermoelectric materials are of interest for converting waste heat to electricity and could be useful in applications such as power generation. Currently bulk bismuth telluride (Bi2Te3) is the most commonly used materials for refrigeration and waste heat recovery. However, theoretical calculation predicts that the performance can be dramatically improved by confining the dimensions of this material.
Electrodeposition provides a bottom-up technique compared to conventional coating methods, such as physical vapor deposition (PVD). It is of advantage in the efficient use of the starting material and can be used to plate curved surfaces and even inside of topologically demanding surfaces. The use of electrodeposition to fill nano-structures is also achievable, which is exploited in the Damascene process to grow 20 nm diameter Cu wires.
In electrochemical experiments water is the most commonly used solvent but its limitation includes narrow potential window, which is crucial in electrodeposition as water reduction will be a competing process as for metal reduction/deposition and provides introduces complexity to experiments. Here we employ an electrolyte system based on tetrabutylammoniumchlorometallate metal sources with compatible tetraalkyl halide supporting electrolytes in non-aqueous, weakly coordinating solvents, which provides the ability to deposit alloys with desired structures and properties.
In this work we report the deposition of Bi2Te3 films from dichloromethane. Bi2Te3 is a narrow band gap layered semi-conductor and it is demonstrated that the composition and structure of the BiTefilms can be controlled by tuning the electrochemical parameters, such as the electrolyte concentration and deposition potential.
報告人簡介：
孟令聰，男，英國南安普頓大學化學系研究員。2010和2012年在中南大學材料學院獲得學士和碩士學位，2016年在英國華威大學獲得理學博士學位。2016至今分別在英國華威大學從事博士后研究員和英國南安普頓大學擔任研究員職務。其目前主要從事于基礎電化學、高溫高壓電化學、電沉積功能材料等領域的研究工作。在國際知名期刊，如ACS Nano、J. Phys. Chem. C、Faraday Discussions等上發表十余篇代表性論文。
