Ko Pui Kei

Hong Kong University of Science and Technology | UST · Department of Chemistry

Quantum information science has garnered significant attention due to its potential in solving problems that are beyond the capabilities of classical computations based on integrated circuits. At the heart of quantum information science is the quantum bit or qubit, which is used to carry information. Achieving large-scale and high-fidelity quantum...

Chiral semiconducting nanomaterials offer many potential applications in photodetection, light emission, quantum information, and so on. However, it is difficult to achieve a strong circular dichroism (CD) signal in semiconducting nanocrystals (NCs) due to the complexity of chiral ligand surface engineering and multiple, uncertain mechanisms of chi...

In this review, the recent development of blue perovskite light‐emitting diodes (PeLED) are summarized. On deep‐blue (≤465 nm) perovskite nanomaterials of different structural forms are mainly focused, including nanocrystals (NCs), quantum dots (QDs), nanoplatelets (NPLs), quasi‐2D thin film, 3D bulk thin film, as well as lead‐free perovskite nanom...

The halide migration effect in mixed-halide lead-based perovskite is a serious problem hindering the development of its display technology. In this study, we have successfully addressed this issue by reporting formadinium (FA) doped mixed-halide perovskite nanocrystals (NCs) with ultra-deep-blue emission of 450 nm, narrow bandwidth of 16 nm, and a...

Lead‐free low‐dimensional organic–inorganic metal halides have gained increasing attention in a wide range of applications due to their low toxicity, outstanding optical performance, and structural tunability. In this work, a general method of incorporating organic molecule into sodium antimony bromides is introduced. The 1D Na 3 SbBr 6 (C 2 H 6 OS...

Despite recent advances, it is still difficult to fabricate deep blue‐emitting perovskite light‐emitting diodes (LEDs) that are immune to the color instability caused by halide mixing. This is largely because it is still challenging to achieve bright, stable, pure bromide perovskite materials with deep blue emission. Here, a novel strategy is repor...

Metal halide perovskite nanoplatelets (NPLs) have demonstrated excellent optical properties for light‐emitting applications and achieved tunable blue luminescence through thickness control. However, their translation into electronic devices has lagged behind due to poor colloidal and film stability. The main reason for this is the deprotonation of...

Metal halide perovskite nanoplatelets (NPLs) have demonstrated excellent optical properties for light‐emitting applications and achieved tunable blue luminescence through thickness control. However, their translation into electronic devices has lagged behind due to poor colloidal and film stability. The main reason for this is the deprotonation of...

Producing efficient blue and deep blue perovskite LEDs (PeLEDs) still represents a significant challenge in optoelectronics. Blue PeLEDs still have problems relating to color, luminance, and structural and electrical stability so new materials are needed to achieve better performance. Recent reports suggest using low n states (n = 1, 2, 3) to achie...

Ternary metal halides, including perovskites, have become a popular field of study over the last decade. Recently many groups have attempted to replace the lead in lead-based perovskites with other metals while retaining similar optical and electronic properties. While there are several candidates for lead replacement, copper-based ternary metal ha...