报告介绍 报告摘要： Recent advance in solution phase synthesis has made it possible to obtain nanoparticles (NPs) with their dimensions controlled at near-atomic precision for catalytic applications. In this talk, I highlight two examples demonstrated in our lab on the synthesis and self-assembly of Co-, and Cu-based NPs for enhanced electrocatalytic reactions.Monodisperse Co NPs were synthesized via thermal...

报告介绍 Abstract： The deep understanding of the physical properties of 2D materials requires the study crossing over from microscopic to macroscopic. New quantum phenomena emerge at the mesoscopic and macroscopic level, such as interference effects, quantum confinement effects, and charging effects. For structures with scales larger than 100 nanometers, the ab initio calculations are unfeasible. Tight-bind...

报告介绍 Abstract： Computational chemistry has become a more and more important technique in scientific discovery process. It has been recognized that the computational chemistry methods "can be used to study all kinds of chemistry; from the molecules of life to industrial chemical processes. Scientists can optimise solar cells, catalysts in motor vehicles or even drugs, to take but a few examples.&quo...

报告介绍 Abstract： The remarkable performance of lead halide perovskites in solar cells comes from the long carrier lifetimes and low non-radiative recombination rates, the same physical properties that are ideal for lasers and light-emitting devices (LEDs). I will first discuss a general growth mechanism of anisotropic nanomaterials, in which screw dislocation defects provide the self-perpetuating steps to...

报告介绍 Abstract： Stretchable and wearable electronics is attracting intensive attention due to their promising applications in many areas where electronic devices undergo large deformation and/or form intimate contact with curvilinear surfaces. On the other hand, a plethora of nanomaterials with outstanding properties have emerged over the past decades. In this talk, I will summarize recent advances in st...

报告介绍 Abstract： The problem of unconventional magnetism in materials without d and f electrons has attracted continuous attention. In particular, a lot of efforts have been devoted to understand the origin and effects of magnetic moments induced in graphene with structure defects such as missing carbon atoms, absorption of light atoms such as hydrogen or fluorine. We have measured the magnetoresista...

报告介绍 Abstract： The fundamental energy gap of a solid is not only an excitation energy but also a ground state energy difference (ionization energy minus electron affinity). The corresponding gap in the band structure of the exact Kohn-Sham theory is less than the fundamental gap, as found by Perdew and Levy, and by Sham and Schlueter, in 1982. The reason is that a multiplicative effective potential that...

报告介绍 Abstract： Ultrafast nonlinear spectroscopy and microscopy are powerful approaches for obtaining structural features, equilibrium dynamics, and spatial arrangements of molecular systems. In this talk, I will first describe the application of ultrafast two-dimensional infrared (2D-IR) spectroscopy to oligopeptides that serve as a paradigm for studies of backbone conformations in proteins. Using multi...

报告介绍 Abstract： The photo- and electro-catalysts play a critical role in clean energy generation and conversion technologies. Although the precious metal-based materials are widely recognized as superior catalysts for energy applications, their large-scale commercial use has been hindered by their expensive and scarcity nature. The development of high performance, plentiful and cheap nonprecious-metal ca...

报告介绍 Abstract： In this talk, I will summarize the recent research on synthesis, characterization and applications of two-dimensional nanomaterials in my group. I will introduce the synthesis and characterization of novel low-dimensional nanomaterials, such as graphene-based composites including the first-time synthesized hexagonal-close packed (hcp) Au nanosheets (AuSSs) on graphene oxide, surface-...

报告介绍 Abstract： 　　Motivated by the problem of time optimal control of two level quantum systems, we investigate the role of symmetries in general time-optimal control problems. If a symmetry is present the underlying (reduced) orbit space where the geodesics are studied is not simply a manifold but it has a reduced dimension and the structure of a stratified space. We study the relationship betwee...

报告介绍 报告摘要： 宇宙射线成因核素41Ca（半衰期约十万年）作为年代计和示踪剂在考古学、生物医学和地质学等许多领域都具有十分重要的科学意义和实用价值。然而，由于自然界里的41Ca含量极其低，目前还不能够实现对其进行准确测量。在各种高灵敏的分析手段中，加速器质谱（AMS）是最有可能实现自然界41Ca准确测量的分析手段之一。报告内容包括：AMS原理介绍、国内外发展现状、41Ca应用的意义以及AMS对41Ca测量存在的关键问题和挑战等。报告...

报告介绍 Abstract：　　In this talk, we first highlight issues with orbital related theory in predicting molecular reactivity. Conceptual density functional theory is then introduced next, whose strength and weakness are both showcased. The main purpose of this talk is to introduce to the audience a new recent effort to appreciate and entertain molecular reactivity using simple density functionals, which is ...

报告介绍 Abstract： Solar energy conversion, particularly solar-driven chemical fuel formation, has been intensely studied in the past decade as a potential approach for renewable energy generation. Efficient solar-to-fuel conversion requires artificial photosynthetic systems with strong light absorption, long-lived charge separation and efficient catalysis. Colloidal quantum confined nanoheterostructures ha...

报告介绍 Abstract： Here, I will present our systematic investigation of a K–O2 battery that uses K+ ions to capture superoxide (O2-) to form the thermodynamically stable KO2 product. This allows for the battery to operate through the facile one-electron redox process of O2/ O2-. Without the use of catalysts, the battery shows a low discharge/charge potential gap of less than 50 mV at a modest current ...

报告介绍 Abstract： 　　This talk will focus on a special class of functional polymers, made up from polymerization of ionic liquids (ILs). They are commonly termed poly(ionic liquid)s or polymerized ionic liquids (PILs). In such a structure configuration, some unique properties of ILs are incorporated into the macromolecular architecture. This inno...