Professor Raymond Wong, Dr Qian Liu and Japanese scholars jointly publish research on novel nanosheet in "Nature Communications"
Professor Raymond Wong (left) and Dr Qian Liu (right) and their partners in Japan develop a nanosheet which offers a promising energy conversion system.

Professor Raymond Wong, Head and Chair Professor of our department and Elizabeth Law Endowed Chair of Advanced Materials of HKBU, Dr Qian Liu, HKBU PhD alumna and the team of Professor Hiroshi Nishihara from The University of Tokyo, Japan collaborated on a research project entitled "A photofunctional bottom-up bis(dipyrrinato)zinc(II) complex nanosheet" through which they developed a new promising nanomaterial which can be used as an active layer for photoelectric energy conversion. The paper was published in leading academic journal Nature Communications ( The work was also highlighted via Nature Japan twitter.

In the study, a novel photofunctional bottom-up nanosheet containing the photoactive bis(dipyrrinato)zinc(II) complex motif was fabricated. The new material is able to convert energy from light into electrical energy.

A single-layer nanosheet measuring 10 μm on one side, which is large for bottom-up nanosheet materials, can be deposited repeatedly on a flat substrate resulting in quantitative layering. Professor Wong said, “A significant advantage of the bottom-up synthesis is that structures and properties can be customized in the process through the selection of components, for instance, metal ions and organic ligands.”

Two-dimensional (2D) polymeric nanosheets have recently gained a lot of attention, particularly top-down nanosheets such as graphene and metal chalcogenides that are produced by slicing bulk layered mother materials. Although bottom-up nanosheets manufactured directly from molecular components can exhibit greater structural diversity than top-down nanosheets, the bottom-up nanosheets reported thus far lack useful functionalities. The new nanosheet in this study stands out from previous bottom-up nanosheets because of its ability to efficiently collect visible light. The study also shows the ease in which various substrates can be deposited to produce a platform with photoelectric conversion function.

Professor Wong added that this novel molecule-based bottom-up nanosheet possessing photofunctionality could lead to more research into creating useful and promising nanomaterials which will in turn open up new areas where this type of two-dimensional nanomaterials can be applied.

from HKBU eNews