题 目:Photo(redox)-active and photo-switchable materials: a journey from molecular design to applications
主讲人:劳伦·鲁尔曼(法国斯特拉斯堡大学教授)
时 间:2023年5月5日(星期五)下午15:30 – 17:00
地 点:化学馆241报告厅
主讲人简介:
劳伦·鲁尔曼教授(Prof. RUHLMANN Laurent)是法国知名的资深电化学专家和光电催化材料学专家,并且是法国国家研究署French national research agency(ANR)三个学术委员会的委员,E-COST POCHEMON的委员,2017年任GDR MAPYRO的委员;他在新材料的设计与电化学合成,光催化、电催化技术, 光谱电化学,有机和无机化合物的纯化、表征和研究,光化学和顺磁和反磁核磁共振技术, 自由基的检测,光电催化还原NO2、CO2、NO3-、Cr(III)、Cr(IV)等污染物,电化学方法保护环境等领域有着深厚的经验和优秀的成果。已在J. Am. Chem. Soc.,Angew. Chem. Int. Ed, Chem. Comm. 等期刊上发表200余篇学术研究论文,多篇论文被评为“Hot Paper热点论文”。目前担任Angewandte Chemie,Journal. American Chemical Society, Chemical Communication, Chemistry - A European Journal等20余个国际著名期刊的审稿人或编委。他作为项目负责人已完成欧盟、法国和德国科研项目20余项,劳伦·鲁尔曼教授曾与L'ORÉAL GROUP,SOLVAY等多家欧美企业有科研项目合作(涉密),目前也是法中高端品牌联合会的主席。2017年,劳伦·鲁尔曼教授被评为法国特级教授;2018年度劳伦·鲁尔曼教授被兼聘为中国国家外专局教科文卫高端外国专家(项目编号:GDW20183300465);2020年, 劳伦·鲁尔曼教授入选浙江省高端引才名单;2022年劳伦·鲁尔曼教授被聘为清华大学Polyoxometalates期刊副主编。截至2018年底,组织国际学术会议九次,本人及其科研团队在国际会议中做重要口头报告或讲座九十一次,学术墙报八十八次。
讲座内容概要:
The conference will be divided into two parts. The first part will be on the development of hybrid systems incorporating polyoxometalates (POMs) which is a promising approach to elaborate new redox active materials. To expand the practical applications, their association to a visible-light photosensitizer is needed and has been explored. In this context, we have also developed a method of electropolymerization of POMs based on nucleophilic attack onto the electrogenerated porphyrin radical cation or dications. The formation of hybrid POM-porphyrin copolymeric films (Fig. 1bc) can be obtained by the electro-oxidation of porphyrin in the presence of the hybrid POM bearing two pyridyl groups (Py-POM-Py). This process is feasible for various type of POMs such as Dawson, Lindqvist or Keggin type POMs.Using the same methodology, the synthesis of a diarylethene-porphyrin photoswitchable copolymer has been developed. The incorporated diarylethene maintains its reversible photochromism upon the UV-Vis radiation with multiple cycles of ring-opening and closing. Stable isoporphyrin [6,7] – POM copolymers have been also develop recently showing interesting properties even upon the NIR illumination. A second methodology is also proposed to form hybrid POM-porphyrin films: first the formation of cationic polyporphyrin electropolymer. Then, by metathesis reaction, the (partial) exchange onto the surface of the initial counter ions by the POMn- or by the nanoparticles stabilized with POMn-. The photovoltaic performances of these hybrid materials have been investigated by photocurrent transient measurements under visible-light illumination given by now good efficiency. In the second part, the photoredox-switchable molecular grippers based on resorcin arene cavitand platforms equipped with alternating quinone (Q) and quinoxaline walls carrying hydrogen bond donating groups will be presented briefly. The semiquinones (SQ) state can be generated electrochemically and photochemically. It was shown that these systems adopt an open conformation in the oxidized Q state until redox interconversion to the paramagnetic SQ radical anion provides the stabilization of the closed form through hydrogen bonding.