News & Events

Date: January 22, 2026 (Thursday)
Time: 14:15 - 17:45 (Registration starts at 14:00)
Venue: Tam Wing Fan Innovation Wing Two, G/F, Run Run Shaw Building, HKU
Keynote speaker: Professor Mercouri G. Kanatzidis, Northwestern University

All members of the HKU community and the general public are welcome to join. Seats for on-site participants are limited. Interested parties please register through the link below by January 22, 2026 (Thursday), 14:00: 

https://hkuems1.hku.hk/hkuems/ec_hdetail.aspx?guest=Y&ueid=104691 

A confirmation email will be sent to participants who have successfully registered.

Abstract

Three- and two-dimensional (3D and 2D) halide perovskites are a broad class of organic-inorganic compounds that, over the past decade, have emerged as exceptional semiconducting materials due to their superior carrier lifetimes and structural versatility. Clearly, a deeper understanding of the roles of Pb2+, and Sn2+, the role of organic spacers on the structure, properties, and performance of these devices is now essential.

Perovskitoids are a separate class related to perovskites and have emerged as having broad structural and compositional diversity that is even greater than that of perovskites. Recent insights are shedding light on the types of organic spacer cations that can effectively stabilize various structures. We hypothesized that perovskitoids, with their robust organic-inorganic networks, could suppress ion migration in solar cells and improve both stability and performance. By exploring a set of perovskitoids of varying dimensionality, we found that cation migration within perovskitoid-perovskite heterostructures was effectively suppressed, leading to improved long-term stability. Increasing perovskitoid dimensionality enhances charge transport, octahedral connectivity, and out-of-plane orientation. The 2D perovskitoids (Organic cation) 8Pb7I22 provide efficient surface passivation and enable uniform large-area films, resulting in perovskite solar cells with a certified power conversion efficiency of 24.6% (Nature 2024, 633, 359–364). This presentation will explore current knowledge of structure-property relationships and provide guidelines for selecting and incorporating organic spacers into crystalline materials and optoelectronic devices.

About the keynote speaker:

Professor Mercouri G. Kanatzidis, Northwestern University

Professor Mercouri Kanatzidis was educated at the Aristotle University of Thessaloniki to earn a bachelor’s degree in Chemistry in 1979. He received his Ph.D. degree in chemistry from the University of Iowa in 1984. He was a postdoctoral fellow at the University of Michigan and Northwestern University from 1985 to 1987. He became an assistant professor at Michigan State University in 1987. He was promoted to full Professor in 1994. He moved to Northwestern University in 2006. In 2006, he moved to Northwestern University, where he currently holds the Charles E. and Emma H. Morrison Chair Professorship. In 2006, he also became a Senior Scientist at Argonne National Laboratory.  His research interests focus on the design, discovery, and synthetic science of new materials, coupled with in-depth characterization, manipulation of new substances with novel and exotic chemical, physical, or electrical properties. At Argonne, particular emphasis is placed on superconducting materials and quantum materials. Professor Kanatzidis has received a number of awards and has been elected to the NAS, AAA&S, FRSC.

Panellists:

Professor Yi Hou, National University of Singapore

Professor Yi Hou is a Presidential Young Professor in the Department of Chemical and Biomolecular Engineering at the National University of Singapore (NUS), Head of the Solar Energy Research Institute of Singapore (SERIS), and an Editor of the IEEE Journal of Photovoltaics. His research focuses on perovskite-based tandem photovoltaics, spanning device physics, materials engineering, and scalable manufacturing. He has achieved multiple world-record solar cell efficiencies, published in leading journals including Science, Nature, and Nature Energy, and is recognized as a top 1% Clarivate Highly Cited Researcher. An MIT Technology Review Innovators Under 35 honouree, he founded Singfilm Solar to translate high-efficiency perovskite technologies into commercial products for consumer electronics and emerging space applications.

Professor Anita Ho-Baillie, The University of Sydney

Professor Anita Ho-Baillie is the John Hooke Chair of Nanoscience at the University of Sydney, a 2020 Australian Research Council Future Fellow and an Adjunct Professor at University of New South Wales (UNSW) until 2025. She completed her PhD at UNSW in 2005. She is a highly cited researcher from 2019 to 2025. In 2021, she was named the Top Australian Sustainable-Energy Researcher by The Australian Newspaper Annual-Research-Magazine. She won the Royal Society of NSW Warren Prize in 2022. In 2024, she received the Nancy Mills Medal from the Australian Academy of Science. In 2024 and 2025, she was named Scientist of the Year and Academic of the Year, by the Australian Space Awards, respectively. In 2025, she won the Australian Museum Eureka Prize for Sustainability Research and the NSW Premier’s Prize for Excellence in Mathematics, Earth Sciences, Chemistry or Physics. She is a Fellow of the Australian Institute of Physics, the Royal Society of New South Wales and the Royal Society of Chemistry.

Professor Qichun Zhang, City University of Hong Kong

Professor Qichun Zhang received his B.S. at Nanjing University in 1992, completed his Ph.D. in chemistry at University of California Riverside in 2007 and did his postdoctoral research at Northwestern University (USA). In 2009, he started his independent career at Nanyang Technological University. In 2020, he moved to City University of Hong Kong. He won the 39th Khwarizmi International Award. From 2018 to 2025, he has been recognized as one of highly-cited researchers (top 1%) in Clarivate Analytics. His research focuses on carbon-rich conjugated materials and their applications. Currently, he has published ＞630 papers and 20 patents (H-index: 122).

Professor Wallace Choy, The University of Hong Kong

Professor Wallace C. H. Choy is a full professor in the Department of Electrical and Electronic Engineering at HKU. His research interests cover organic/inorganic optoelectronic devices, flexible and transparent conducting nanostructures, metal oxides, and nanomaterial devices. He has published over 270 peer-reviewed papers, several book chapters, and holds patents, in addition to editing one book. He was recognized as the top 1% of most-cited scientists in Thomson Reuters’ Essential Science Indicators from 2014 to 2024. He has served as a Member of the Engineering panels of the Hong Kong Research Grant Council, an Assessor of the Enterprise Support Scheme Assessment Panel of the Innovation and Technology Commission of Hong Kong, and a Specialist/Panel of the Hong Kong Council for Accreditation of Academic and Vocational Qualifications. He is an elected fellow of OSA/ Optica.