PolyU researchers unlock the potential of 2D organic perovskites in electronics – Asia Pacific

A discovery by a research team led by Prof. LOH Kian Ping and Dr. Kathy LENG of the Hong Kong Polytechnic University (PolyU) has pushed the field of materials science to a new frontier.

Their research, recently published in the journal Science, reveals a breakthrough in the synthesis of fully organic two-dimensional (2D) perovskites, marking a significant advance in the field of 2D materials.

Perovskites, named for their structural similarity to the mineral calcium titanate perovskite, are known for their properties applicable to a variety of fields including solar cells, lighting and catalysis. Traditionally, perovskites have been studied as inorganic compounds, but Prof. Loh’s team has shifted focus to the emerging class of fully organic perovskites, where organic molecules replace individual atoms in the A, B and X constituents.

The team’s innovative approach circumvents the challenges of synthesizing fully organic 3D perovskites by instead focusing on 2D layers, a strategy aimed at integrating a broader range of organic ions. This groundbreaking method led to the development of the “Choi-Loh-v phase” (CL-v) perovskites, named after Dr. Choi and Prof. Loh. These molecularly thin layers, stabilized by van der Waals forces, exhibit extraordinary properties and can be exfoliated into hexagonal flakes just nanometers thick.

One of the most exciting aspects of this discovery is the solution processability of 2D organic perovskites, which offers promising possibilities for applications in 2D electronics. The research team’s measurements of the dielectric constants of the CL-v phase have yielded impressive values, exceeding those of commonly used materials such as silicon dioxide and hexagonal boron nitride. This breakthrough paves the way for the integration of the CL-v phase as a dielectric layer in 2D electronic devices, significantly improving their performance.

The contribution of Dr. Leng’s work on the project involved the successful integration of 2D organic perovskites with 2D electronics, with the CL-v phase serving as the top gate dielectric layer. By combining advanced manufacturing techniques with the unique properties of the CL-v phase, the team achieved superior control over current flow in transistors, surpassing the capabilities of conventional dielectric layers.

Prof. Loh’s research not only introduces a new class of fully organic perovskites, but also demonstrates their potential for improving the performance of 2D electronic devices.