Research Achievements
Congratulations to Prof. Raymond Wong, Dean of Faculty of Science, on receiving the successive endowed professorship - Clarea Au Endowed Professorship in Energy! The professorship has strengthen his research in developing new molecular and nano materials for energy conversion.
Meanwhile, Prof. Wong’s research project on the topic, “Development of new, stable, highly efficient blue emissive materials that can be processed by wet methods, and the associated large-area solid-state lighting technologies”, is supported by the National Key R&D Program – International Science and Technology Cooperation Project with a funding of RMB 4.2 million. PolyU is the only granted Hong Kong institution in that round of the exercise. The project will focus on the design, synthesis and characterisation of various blue light-emitting materials; and facilitate the commercialisation of the related technologies.
恭喜院長黃維揚教授獲繼任勵學教授席 —— 歐雪明能源教授席。勵學教授席加強了黃教授開發適用於能源轉換的新分子及納米材料的研究。
與此同時，黃教授的研究項目「可溶液加工、高效率、高穩定藍光材料與大面積固態照明器件研究」獲 「國家科技部重點研發計劃 —— 國家國際科技合作專項」撥款人民幣 420 萬元支持。理大是唯一一間在本輪計劃獲資助的香港高校。項目將聚焦於發展各種藍光發光材料，涵蓋其設計、合成和表徵探索，務求促進上述技術的產業化進程。
Improving carrier mobility in two-dimensional semiconductors with rippled materials – “Nature Electronics”
Dr Yang Ming and his team developed an approach to realise record-high carrier mobility in the 2D semiconductor MoS2. The team showed that by conforming to bulged substrates, the rippled structures could be introduced in the 2D MoS2, which not only resolves the low carrier mobility in 2D semiconductors at room temperature and leads to an increased intrinsic dielectric constant of MoS2 but also can effectively suppress the phonon scattering.
晶格彎曲增强二維半導體載流子遷移率
─《自然─電子學》
楊明博士及其團隊成功利用彎曲基底，在二維半導體（二硫化鉬）中引入彎曲的結構，可增加二維半導體内稟的介電常數，并有效地減弱室溫下的聲子散射，從而解決了二維半導體的載流子遷移率在室溫下會下降的問題並實現了室溫下超高的載流子遷移率。
Multiple exciton generation in tin-lead halide perovskite nanocrystals for photocurrent quantum efficiency enhancement – “Nature Photonics”
Dr Li MingJie and his team have recently developed high-quality halide perovskite nanocrystals with enhanced multiple exciton generation (MEG). Nanocrystals (also known as quantum dots) developed by rational design can convert a high-energy photon into multiple electron-hole pairs, breaking the power conversion efficiency limit. The team successfully demonstrated that the internal quantum efficiency exceeded 100% at a low threshold using such perovskite nanocrystals for the first time.
鈣鈦礦納米晶體中的多重激子效應以提高光電流量子效率
─《自然─光子學》
李明杰博士帶領的研究團隊開發了具有增強多重激子效應的鹵化物鈣鈦礦納米晶體。通過合理設計的納米晶體 (或稱為量子點) 能將高能光子轉化為多個電子電洞對，突破光電轉換效率的極限。更重要的是團隊首次證明了使用這種新設計的納米晶體，內部量子效率在低閾值下能超過 100%。
Ferroelectricity in untwisted heterobilayers of transition metal dichalcogenides – “Science”
Prof. Daniel Lau, Head of the Department and his research team have achieved a significant breakthrough in 2D ferroelectric materials. The team has shown how the widely known nanomaterials molybdenum disulfide (MoS2) and tungsten disulfide (WS2), although not ferroelectric by themselves, can be stacked to form a new heterogeneous crystal that is ferroelectric in nature. It happens through the interaction of the atoms of both materials with each other. The final product is only two molecular layers thin, at the very limit of what nano-sized means. This discovery is an important step to making ultra-thin electronics at a low cost and high reproducibility rate, creating new 2D ferroelectric materials.
非轉角過渡金屬硫族化合物雙層異質結中的鐵電性
─《科學》
應用物理學系系主任劉樹平教授及其研究團隊，在鐵電材料研究領域上取得了重大的突破。劉教授發現納米材料二硫化鉬 (MoS2) 和二硫化鎢 (WS2)，雖然兩者本身不是鐵電體，但可以堆疊形成一種新的、具備鐵電性的異質晶體。這種新的鐵電薄膜是通過兩種材料的原子之間的相互作用形成。最終的成品只有兩個分子層，處於納米尺寸的極限。 這項發現是以低成本和易複製的方法來製備超薄電子產品的重要一步，更開拓了二維鐵電材料家族的領域添加新成員。
