(Young Scholar's Forum, Apr 17) Lectures of School of Materials Science and Engineering
April 15,2018 15:42:27 readCount:42
Venue: Room 502, State Key Laboratory of Luminescent Materials And Devices, Building No.1, Northern Area, Wushan Campus
Time: Tuesday, Apr 17, 2018
Lecture 1
Speaker: Dr. Zhou Jiawang (Northwestern University)
Specific Time: 9:15-10:00
Lecture 2
Speaker: Dr. He Jiating
Specific Time: 10:10-10:55
Lecture 3
Speaker: Dr. Liu Fengjie
Specific Time: 11:05-11:50
Lecture 4: Rational Material and Interface Engineering to Improve the Performance and Stability of Perovskite Solar Cells
Speaker: Dr. Zhu Zonglong (The Hong Kong University of Science and Technology)
Specific Time: 14:00-14:45
The potential for perovskite photovoltaics to create transformative energy generation is currently restrained by its reliability issues regard hysteresis and degradation. In order to address these challenges, we have employed an integrated material, interface, and device engineering approach to establish interfacial material design rules to enable rational design of highly efficient and stable devices. This has resulted in devices with both high power conversion efficiency (PCE of >18%) and minimum hysteresis.This integrated design approach will have the potential to address these issues at their source, enabling better and timely design of suitable perovskite compositions and interfacial materials to facilitate technology translation to industry.
Lecture 5: Real Time Liquid Phase TEM Observations of Chain-like and Rod-like ZnO Formation via Oriented Attachment
Speaker: Dr. Liu Lili
Specific Time: 14:50-15:35
Oriented attachment (OA), an important crystal growth mechanism, involves collision of nanocrystals followed by attachment and coalescence with a common crystallographic orientation on planar interfaces to produce lower energy configurations. Up till now, OA has been cited as responsible for particle growth in many systems and for exerting control over the size, shape and morphology of the resulting materials. However, controlling crystal morphology via this process is still a tremendous challenge owing, in part, to the complex impact of growth conditions, such as the influence of ions in solution.Zinc oxide (ZnO) is an attractive II-VI compound semiconductor material with a direct band-gap (Eg = 3.37eV) and a large exciton binding energy (60 meV).. There are only a few reports of preparing ZnO nanorods in a controllable manner by solvent evaporation. But nearly no experiment or simulation results have clarified the detailed mechanism information about ZnO OA formation process because the previous ex-situ transmission electron microscope (TEM) is far insufficient obtain the direct evidence.
Here we report the results of a liquid phase (LP)-TEM investigation aimed at filling these knowledge gaps. We observed the growth of chain-like ZnO from primary particles in both methanol and aqueous solution. In the absence of added Zn salts, even at the lowest electron doses possible, the primary particles underwent dissolution, presumably owing to the effects of electron-beam induced radiolysis on solution speciation. None-the-less, coalescence events did occur, resulting in chain-like ZnO structures with a high degree of crystallographic co-alignment. Addition of Zn2+ions to solution prevented dissolution and enabled imaging of both classical nanocrystal growth and oriented attachment. The approach reported here overcomes the problem of dissolution common to LP-TEM studies of mineral systems and the results provide insights into the growth of this important oxide semiconductor.
Lecture 6: Nanoparticle-Mediated Delivery of Iron Chelators as a Novel Therapy for Iron Overload Diseases
Speaker: Dr. Liu Tianqing
Specific Time: 15:40-16:15
Iron loading haemoglobinopathies, such as β-thalassaemia, are treated with iron chelators to remove excess iron. Deferoxamine (DFO) is an effective iron chelator with a favorable safety profile, but an onerous parenteral administration regimen limits its routine use. In order to develop more effective methods for delivering iron chelators, we have examined whether amphiphilic copolymer nanoparticles (NPs), can be used to deliver DFO more efficiently. We found DFO-NPs were much more effective at depleting iron than free DFO using cellular models and three different iron overload animal models. Pharmacokinetic analysis showed that NP-encapsulated DFO had a much longer half-life than free DFO, and that DFO-NPs could be readily taken up by tissues, and, in particular, by hepatic Kupffer cells.
Iron accumulation has been reported in neurological disorders as well. Iron chelation therapy using deferoxamine (DFO) may inhibit this nigrostriatal degeneration and prevent the progress of PD. We used a polymeric nanoparticle system modified with brain targeting peptide rabies virus glycoprotein (RVG) that enables intracerebral delivery of DFO. Administration of these nanoparticles significantly decreased iron content and oxidative stress levels in the brain of PD mice and effectively reduced their dopaminergic neuron damage as well as reversed their neurobehavioral deficits, without causing any overt adverse effects in the brain or other organs. This novel DFO-based nanoformulation holds great promise for safe and effective delivery of DFO into brain and for realizing iron chelation therapy in PD treatment.
Lecture 7
Speaker: Dr. Hou Shuang
Specific Time: 16:20-17:05

Announced by School of Materials Science and Engineering