Biomimetic Optoelectronics with Nanostructures
基于微纳结构的仿生光电子器件
Zhiyong Fang（范智勇）
ABSRACT
Billions of years of natural evolution have created today's colorful biological world. Biomimetics have given us many inspiring ideas for solving scientific and engineering problems for more than 100 years. From a material perspective, many biological structures are made of nanomaterials with intriguing capabilities to manipulate light propagation. In this talk, the speaker will firstly briefly summarize some inspirations from micro-nano biomimetics that have led to unique designs of optical and optoelectronic devices, including solar cells, light-emitting diodes and photodetectors. Then the speaker will focus on one example which is a unique spherical bionic electrochemical eye. The key component of the bionic eye is a hemispherical retina which is made of a high-density perovskite nanowire array grown by the vapor phase method. We use ionic liquid as the front common electrode of the nanowire, and the liquid metal wire as the back contact electrode of the nanowire light sensor, mimicking the optic nerve fiber behind the retina. Device measurement shows that the electrochemical eye has high responsivity, reasonable response speed, lower detection limit and wider field of view, as well as basic imaging functions. In addition to the structure similar to the human eye, the nanowire density of the hemispherical artificial retina is higher than the density of the photoreceptor in the human retina, so it has the potential to achieve higher image resolution if individual photoreceptors are addressed.
数十亿年的自然进化创造了当今多彩的生物世界，而百多年来仿生学已经给了我们许多解决科学和工程问题的重要思路。从材料的角度来看，许多生物结构都是由具有光学调控功能的微纳结构组成。这些结构都有提高生物光学器件效能的功用。本报告将首先简要介绍一些生物微纳光学结构，以及从这些生物器件得到的一些仿生技术的灵感。在此启发之下，一些独特的光电器件已经被设计和制成，包括太阳能电池，发光二极管和光电探测器等。然后，本报告将介绍一种特殊的球形仿生电化学眼，其半球形视网膜是通过气相法生长的高密度钙钛矿纳米线阵列制成的。我们使用离子液体电解质用作纳米线的正面公共电极，液态金属线用作纳米线光传感器的背接触电极，同时仿生视网膜后的视神经纤维。器件测试表明，电化学眼具有高响应度，合理的响应速度，较低的检测极限以及较宽的视野，还具有基本的成像功能。除了与人眼的结构相似之外，半球形人工视网膜的纳米线密度高于人类视网膜中感光器的密度，因此有实现更高图像分辨率的潜力。
BIOGRAPHY
Dr. Zhiyong Fan received Bachelor and Master degrees on Materials Science from Fudan University, China, then move on to University of California, Irvine for his PhD study. He worked as a postdoctoral fellow in the Department of Electrical Engineering and Computer Sciences at the UC, Berkeley, with a joint appointment at Lawrence Berkeley National Laboratory in 2007~2010. He then joined the Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology (HKUST) in 2010 and now is a full professor. He is a Director of HKUST-ATAL Joint Innovation Laboratory, Associate Director of Material Characterization and Preparation Facility. He is a member of the State Key Laboratory of Advanced Display and Optoelectronics Technologies at HKUST, Fellow of the Royal Society of Chemistry, Senior Member of IEEE, and Founding Member of the Young Academy of Sciences of Hong Kong. He has won a number of awards, including the BSAC Outstanding Research Award, HKUST SENG Young Investigator Award, Outstanding Research Award, HKUST President Award and Innovation Award, and the Shandong Natural Science Second Prize. His research interest is focused on functional nanomaterials and structures for electronic and optoelectronic devices. To date, he has published more than 170 peer reviewed papers in Nature, Nature Materials, Nature Communications, PNAS, Nano Letters, Advanced Materials, etc., with citations ~19,000, H index 69, and is a highly cited author of Clarivate Analytics in 2018.
范智勇，香港科技大学电子与计算机工程系教授，博导。香港科大-ATAL联合实验室主任，香港科大材料表征中心副主任，香港科大能源学院，先进显示与光电子技术国家重点实验室成员，英国皇家化学会会士，IEEE资深会员，香港青年科学院院士，中国化学会会员，中国材料学会纳米材料与器件分会创会理事。复旦大学本科和硕士，加州大学欧文分校材料科学博士。曾任加州大学伯克利分校电气工程和计算机科学系博士后研究员，劳伦斯伯克利国家实验室博士后研究员。获得多项奖项，包括加州大学BSAC杰出研究报告奖，香港科技大学工院青年研究员奖，杰出研究奖及香港科技大学校长奖及创新奖，山东省自然科学二等奖等。研究兴趣集中在可用于电子及光电器件的纳米材料和结构。迄今在Nature, Nature Materials, Nature Communications, PNAS, Nano Letters, Advanced Materials等期刊发表了170多篇学术论文，引用次数~19,000，H指数69，为2018科睿唯安高引作者。