Overarching goal:

Our research focuses on exploring unconventional approaches that integrate synthesis, self-assembly, fluid dynamics, and scalable processing of nano-materials from both organic and inorganic worlds with complementary strengths, well-defined conformation, morphology, composition and electronic properties for energy harvesting and storage applications. The convergence of these interdisciplinary studies provides revealing insights into the development of new generations of hybrid materials with unprecedented materials properties, especially those pertinent to energy harvesting and storage applications. 

1. Leading the Edge: Wafer-scale Epitaxy of Single-crystal, non-Silicon Monolayer Semiconducting Materials with Ultrahigh Mobility

The holy grail of next-generation electronics is to identify viable alternatives for non-Silicon electronics with synthetic scalability, industry-compatible processability, crystallinity, and, most importantly, ultra-high mobility. Chemical vapor deposition (CVD) provides an enabling platform to stitch dissimilar atoms into functional molecules where the periodic and repeated arrangement of lattices is perfect and extends throughout the entirety of the specimen without interruption. The result is the wafer-scale uniformity and unparalleled electronic properties on par with the mechanically exfoliated benchmarks. Current projects straddle across (a) lattice orientations; (b) heterogeneous junctions; (c) dopants; (d) metal contacts; and (e) device integration, respectively. Notable applications include but are not limited to the Internet of Things (IoT), flexible electronics, and next-generation semiconductors.

Collaboration:

Prof. Jeehwan Kim and Prof. Jing Kong at MIT;

Prof. Lance Li at HKU;

Prof. Deep Jariwalla at UPenn;

Prof. Sang-Hoon Bae at the University of Washington, St. Loius;

Prof. Wen-Hao Chang at NCTU, Taiwan;

TSMC

2. Macro-scale Printing of Transition Metal Dichalcogenides Metamaterials with Control of Hierarchy at Nanoscale

The deployment of dimensional transitions is ubiquitous in nature, ranging from the Venus flytrap, the beating of a heart sounds shaped by the vocal folds, and zooming of the focal length by the human eye. External stimuli in the form of chemical or mechanical cues arising from the environment result in the deformation of materials. Such a dimensional transition leads to new functionalities, which cannot be found in their original formats. We explore nature-inspiring synthetic strategies to systematically study the self-assembling behaviors, underlying mechanisms, and the associated material properties, ultimately enabling the microscopic integration and macroscopic deposition of these 2D transition metal dichalcogenides into 3D hierarchical metamaterials. Potential applications include structural reinforcement, energy storage, electrochemical catalysis, responsive smart materials, and sensors.

Collaboration:

Prof. Jing Kong at MIT;

Prof. Richard Kaner at UCLA;

Prof. Han-Yi Chen at National Tsing Hua University;