報(bào)告題目：Controlling functional properties and chemical reaction kinetics in low-dimensional systems
報(bào)告人：德國(guó)明斯特大學(xué)Harald Fuchs院士
報(bào)告時(shí)間：2019年10月18日（星期五）上午10:00
報(bào)告地點(diǎn)：長(zhǎng)安校區(qū)啟翔樓233會(huì)議室
邀請(qǐng)人：黃維院士
承辦學(xué)院：柔性電子研究院
聯(lián)系人：張倩文
聯(lián)系電話(huà)：88460889
報(bào)告簡(jiǎn)介：
The electronic and optical properties of inorganic systems as well as the reaction behavior of organic molecules strongly depend on their dimensionality and/or that of their environment. Thus, controlling the dimensionality as well as the bond order in 0D, 1D and 2D systems at the sub-nanometer scale, their physical properties may qualitatively deviate from that of 3D bulk materials of the same chemical composition. For example, materials such a graphene exhibit excellent mechanical and thermal properties as well as high 2D electronic mobility. However, in their unmodified state these Dirac systems are lacking a finite electronic band gap, required for generating transistors. Graphene nanoribbons, representing 1D systems, on the other hand, allowed to overcome this limitation by using bottom up on-surface chemistry to control the ribbon latitude and thus, the band gap. In contrast, in other 2D systems such as Chalcogenides, finite band gaps are found. However, it is still a technical challenge here to grow large-scale systems with well-defined geometry for application in opto-electronic device. Our recent STM investigations on phosphenes and antimonene using UHV epitaxial growth revealed promising perspectives in these directions [1].
In the case or organic molecules, surfaces represent 1D or 2D spatial confinements for on-surface chemistry allowing a unique regioselective and kinetic control of chemical reaction schemes which otherwise cannot be done in liquid- or gas phase chemistry. In addition, surfaces can act catalytically and by reconstruction or faceting, and the confinement can display one- or zero dimensional character. Advanced LT-UHV Scanning probe techniques (LT-STM, nc-AFM) allow a detailed sub-molecularly resolved analysis of the reaction pathways, including intermediates, while complementary PES techniques (XPS/UPS) reveal the chemical reaction status of molecular systems [2, 3]. A novel type of nc-AFM tip developed in our group allows us to quantitatively characterize individual chemical bonds and even their bond-order with unprecedented precision [4].
Finally, the construction of high performance functional organic opto-electronic devices, following the biological self-organization approach can be done bottom up by combining nanotechnological methods with chemistry. Self-assembled pre-patterned interface layers, for example, allow to grow functional molecular layers in OFET/OSC structures in a well-controlled way, resulting, for example, in a significant increase in charge carrier mobility by more than one order of magnitude, without modifying the chemical systems making up the active OFET channel structures [5]. Similarly, flexible organic photo responsive systems with ultrahigh detectivity can be generated [6].
References:
[1] T. Niu et al.Adv. Mater. 2019, 31, 1902606
[2] G. Wang et al., Nature Chemistry, 9 (2017) 152
[3] L. Liu et al., J. Am. Chem. Soc. 140, (2018) 6000
[4] H. M?nig et al., Nature Nanotechnology 13, (2018) 371
[5] D. Ji et al., J. Am. Chem. Soc. 139 (2017) 2734
[6] D. Ji et al., Nature Comm. (2018) 9 (2018) 2339
報(bào)告人介紹：
Harald Fuchs院士是德國(guó)科學(xué)院院士、德國(guó)工程院院士、歐洲科學(xué)院院士以及發(fā)展中國(guó)家科學(xué)院院士。他于1985年在IBM研究實(shí)驗(yàn)室從事博士后研究工作，1985年至1993年擔(dān)任德國(guó)BASF公司項(xiàng)目主管，1993年至今在德國(guó)明斯特大學(xué)從事研究工作，現(xiàn)任德國(guó)明斯特大學(xué)物理研究所所長(zhǎng)。因?yàn)榻艹龅膶W(xué)術(shù)成就，曾獲得“菲利普莫里斯獎(jiǎng)”、德國(guó)聯(lián)邦十字勛章等榮譽(yù)，在國(guó)際學(xué)術(shù)界有廣泛影響力。今年10月，獲得了2019年度“中國(guó)政府友誼獎(jiǎng)”。
Harald Fuchs院士長(zhǎng)期從事表面化學(xué)反應(yīng)及納米生物領(lǐng)域的研究工作并做出了重要貢獻(xiàn)，是國(guó)際知名的表面化學(xué)及納米生物學(xué)學(xué)者。哈拉爾德??？怂乖菏渴敲魉固卮髮W(xué)納米技術(shù)研究中心的創(chuàng)始人，其研究領(lǐng)域主要集中在納米科學(xué)和納米技術(shù)，在掃描探針技術(shù)、自組裝納米材料、納米生物體系等領(lǐng)域都取得了卓越的成就。迄今已在Nature,Science,Nature Nanotech,Nature Mat.,JACS,Angew.Chem.Int.Ed.,Adv.Mater.等重要期刊發(fā)表論文500余篇，擁有35個(gè)專(zhuān)利申請(qǐng)。
