| 姓名 | 黃奕騰 |
|---|---|
| 職稱 | 助理教授 |
| 學歷 | 英國劍橋大學博士 |
| 電子郵件 | |
| Tel | +886-2-33669544 |
| 辦公室 | 電機二館535室 |
| 研究領域 | Future Research Direction Over the last decade, lead-halide perovskites (LHPs) have emerged as a promising novel material with outstanding performance in solar cells, photodetectors, light-emitting diodes, lasers, and so on. Their fast emergence has been attributed to the extraordinary electronic band structure, which allows them to tolerate high defect densities and hence can be easily processed using facile low-temperature solution-based methods. Nevertheless, the commercialization of LHPs is still faced with the challenges in lead toxicity and instability issue. My research interest hence lies in studying other alternatives to LHPs, or “perovskite-inspired materials (PIMs)”, which are non-toxic, air-stable, while can potentially preserve similar electronic band structures to LHPs. My future research plans can be mainly split into three main topics and include both fundamental and application studies. The topic (I) focuses on the spectroscopic study of PIMs. Since defect tolerance is one of the most important features of LHPs, I will aim to investigate if such a feature can be also replicated by other PIMs. Through the AI screening and density functional theory (DFT) calculations, numerous potential PIM candidates can be identified. These PIMs with different defect densities will be prepared either by tuning stoichiometry of the precursors or applying external treatment (e.g., plasma etching). Afterward, ultrafast spectroscopy will be utilized to investigate the impacts of defects on the carrier dynamics of PIMs. Importantly, optical-pump-terahertz-probe (OPTP) technique will be an ideal tool here because it can not only directly monitor free carrier kinetics, but also provide insightful THz spectra highly associated with the carrier transport features. The topic (II) is to build up models for describing the physics in PIMs and further propose the “selection rules” for finding promising materials in the future. Until now, despite many PIMs being identified, there is still not a single material showing comparable performance to LHPs, suggesting our understanding on the defect tolerance theory is still incomplete. With the analysis on carrier dynamics acquired from ultrafast spectroscopy along with the support from theoretical calculations, I hope to unravel the correlation between defects and carrier lifetimes within PIMs. Additionally, carrier localization was recently observed in many Bi-based PIMs that it has been almost considered as a hallmark. Although carrier localization seems to prevent carriers from recombination with defects in some PIMs, it unfortunately reduces the carrier mobility and thus impedes carrier transport. Therefore, it is also important to develop physics models for describing this unusual phenomenon in PIMs. With the built-up of physics models, I will aim to find out the key characters leading to defect tolerance and propose associated selection rules, which I believe can not only greatly advance the discovery of novel materials, but also benefit conventional semiconductor industries. The topic (III) is to develop practical applications based on PIMs. I had accumulated experience on fabricating PIMs-based solar cells and photodetectors during my PhD period, while PIMs can be applied to far more aspects according to their optoelectronic properties. For example, the self-trapped excitons in (octylammonium)2SnX4 (X = Cl, Br) are suitable for broadband LEDs, while the strong radiation absorption of BiOI is ideal for X-ray detectors. The advantages of low-toxicity, high air-stability, and solution-processability also make several PIMs perfect candidates for wearable optoelectronic devices, which could be applied to indoor photovoltaics (IPVs), Internet of Things (IoT) systems or biomedical microdetectors. In addition, my previous experience on plasmonics can be further integrated with the research in this direction as well. With the help of optical simulation and advanced lithography techniques, various nanostructures could be used to tune the optoelectronic properties of PIMs, and create even more efficient devices. PIMs hence have very great potential in a wide range of applications, and it would be amazing to have more talents involved into this exciting field! |