Research
The Current and Completed Research Projects
1. The Electrical, Optical and Mechanical Properties of Two-dimensional Transition Metal Dichalcogenides/their Hybrid Systems (2017~2020)
2. Degradation on Two Dimensional Materials (2017~2020)
3. The patterned functionalization of Transition Metal Dichalcogenides and their applications for optoelectronic applications (2019~2020)
4. Electrical transport investigation through single defect in Two-dimensional materials (2019~)
5. Learning through projects: advanced characterization technique training using the world's thinnest materials (2019~2020)
6. Engineering the Surface Plasmonic Coupling with Atomic-scale Antennas in Two-dimensional Transition Metal Dichalcogenides (2019~)
7. 快速海水淡化氧化石墨烯(GO)反滲透膜關鍵技術研究 (2020~)
8. Reversible phase transition and lattice direction switching in anisotropic two-dimensional transition metal dichalcogenides (2021~)
9. Three-dimensional Self-assembled Graphene Nanofluidic Chip (2021~)
10. Learning through projects (II): remote lab through home projects (2021~)
11. Generalized Vapor-Liquid-Adatom-Solid (VLAS) synthesis of two-dimensional (2D) transition metal dichalcogenides (TMDC) (2021~)
12. Graphene oxide moisture condenser for high efficiency dehumidifiers (2022~)
13. Precise phase engineering in two-dimensional chalcogenides via localized external stimuli (2023~)
14. 二维材料界面与构效关系 (2023~)
15. 工况下二维半导体晶格缺陷的局域偶极电场测量 (2023~)
16. Scalable two-dimensional polymorphic ferroelectrics towards in-memory processing (2024~, co-PI)
Research Highlights
1. We have synthesized a variety of 2D materials through CVD methods, which has been published in Advanced Materials 36, 17, 2304808 (2024), JACS, 142, 13130 (2020), Advanced Materials, 21, 7723 (2016) and Advanced Science, 7, 2001742 (2020), and we have developed one way by ultraviolet light exposure in humid to selectively oxidize the grain boundaries and atomic vacancies in graphene as well as transition metal dichalcogenide(TMD) materials, which can be seen by optical microscopy. This smart technique can distinguish the chemical activity contrast at the grain boundary and perfect crystals. The chemical reaction activity difference between perfect crystal and defective position as well as strained parts will be the main solution. The UV method can also induced reversible straining in 2D materials. The aforementioned works were published in Advanced Functional Materials 23, 5183-5189 (2013), ACS Nano 8, 11401-11408 (2014), ACS Nano 10, 770-777 (2016), Advanced Functional Materials, 31, 2009166 (2021).
2. We have comprehensively studied the grain boundary (GB) structures and the criterion to determine the position and morphology of GB, relative to the nearby grains. The electrical property of inter-grain was also investigated and compared with the intra-grain size. The impact of GB on resistance in TMD materials are huge, orders of magnitude difference. This work was published in Nature Communications 7, 10426 (2016), and reported in Phys.org, Nanowerk, Nanotechnology Now, etc. We have studied the metal-semiconductor contact with two-dimensional materials by in situ TEM, which shows the clean vdW contact is beneficial for the electrical transport, overcoming the usual Schottky contact with two-dimensional materials. This work is published in Nature Communications, 11, 3982 (2020). We also modulate the defects to create efficient hydrogen evolution in Advanced Materials 36, 17, 2304808 (2024).
3. The interfacial strains have been carefully studied between 2D materials and substrates, the optical and OM characterizations showed the inhomogeneity in strains and puckering from edges. The work was published in ACS Nano 11, 7354-7541 (2017). The interfacial strain between the atomic layers will also affect the generation of dislocations and delamination, this work was published in Nano Letters 16, 7807-7813 (2016). The prestrain induced wrinkles in 2D materials have been characterized in detail, reported by us in the papers on Nano Letters, 20, 8420, 2020, ACS Nano 11, 7354-7541 (2017). The poststrain induced cracks were observed both in ambient conditions and in corrosive conditions, the cracking behavior is highly dependent on environment conditions. These results can be found in our publications on Nature Communications 8, 14116 (2017), Science Advances 6, 47, eabc2282 (2020), Physical Review Letters 125, 246102 (2020).
4. We propose a contamination-free method for transferring 2D materials to and from different substrates. Our ice-aided transfer/stamping method fundamentally solves the contamination issue that has perplexed the scientific community for over a decade. This technique could also help increase the breadth of application, especially in the fields of semiconductors or biomedicine, where the absence of contaminants is critical. Moreover, we also observed the ultralow friction between two-dimensional (2D) ice, a solid phase of water confined to the 2D space, and the 2D materials. The results can be found in our publications on Advanced Materials 35, 14, 2210503 (2023) and Nano Letters 23, 4, 1379–1385 (2023).
The philosophy of the research in our group can be described as the chart below:
Recently, we also summarized our work and gave perspective in 1. the fundamental research of GBs and boost the wide application of multifunctional devices (Acc. Chem. Res., 54, 22, 4191–4202 (2021)), 2. developing of precision chemistry down to an atomic scale for 2D materials (Acc. Mater. Res., 2, 10, 863–868 (2021)), 3. new insights into the interactions between two-dimensional ice and two-dimensional materials (Droplet, 2, 4, e88 (2023)), 4. Comprehensive review on clean transfer of 2D materials (ACS Nano, (2024)), 5. Scanning Probe Microscopies for Characterizations of Two-Dimensional Materials (Small Methods, (2024)) and 6. Ferroic Phases in Two-Dimensional Materials (Chem. Rev.,123, 10990-11046 (2023)).
