Joint Laboratory Funding Scheme Layman Summaries of Projects Funded

System for 2/3/4D Additive Manufacturing of Supra-nano Metallic Materials for Biomedical and Lightweight Structure Applications
Joint Laboratory: IMR-CityU Joint Laboratory of Nanomaterials & Nanomechanics
Project Coordinator: Prof Jian Lu (CityU)

Abstract
The Joint Laboratory of Nanomaterials and Nanomechanics has been founded with the support of Croucher Foundation since 2008. We have been recognized as one of the four “outstanding joint laboratories” in an evaluation of the laboratories jointly established by CAS and academic institutions in HK in 2018. This project is the integration of a key equipment for the future development of this fruitful collaboration.

Breaking the limitations of shape due to production and reaching the materials properties as designed according to the applications are always the pursuits of the goal for the materials researchers and the engineers in different areas. In this project, we will explore a systematic way to produce 3D printed materials with desired mechanical properties for biomedical and lightweight structure applications. We will first set up a 2/3/4D additive manufacturing system to fabricate metallic-based materials (such as Ti-based, which are widely used in biomedical and lightweight structure applications) and examine the mechanical properties of the printed materials. Due to the different requirements of mechanical properties of different parts for different applications, we will apply our knowhow gained in inventing 4D printing technique (published in Science Advances), producing surface nanostructured materials and fabricating supra-nano materials (published in Nature) to further treat the 3D printed materials to enhance their mechanical properties according to the requirements. At the end of the project, we will be able to integrate the 3D printing with the post- treatments with different parameters to obtain a map of printed metallic products with various structure, mechanical properties and potential applications. Our endeavors would facilitate applications in medical implants with high wear resistance and light-weight parts with high strength, benefits to the whole society.

The proposed research will be composed of 3 main tasks: (1) Set up the 2/3/4D additive manufacturing system of metallic materials and study the mechanical properties of the printed materials; (2) Study the effect of post-treatment (such as Surface Mechanical Attrition Treatment and Physical Vapor Deposition) on the mechanical properties of the printed materials; (3) Study the potential applications of the printed materials obtained by this proposed equipment.


Development of 3D Integrated Robotics and Sensing Structures using Multi-layered Nano-ink Circuit Deposition
Joint Laboratory: Joint Laboratory for Robotic Research
Project Coordinator: Prof Wen-jung Li (CityU)

Abstract
Three-dimensional (3D) printed electronics process is a foundation technology for the development of advanced sensing and robotics actuation systems, and offers the capability of integrating complex geometric features, compact electronic circuits, and many new functional materials with excellent mechanical properties. Coupled with other emerging digital mechanical fabrication technologies, such as multi-material 3D printing techniques, researchers will be able to employ self-organization for fabrication and increase structural complexity for robotics actuators. Hence, the multi-material 3D printers are increasingly important in order to directly manufacture the functional body of a robot that employs different soft material components with stiffness gradient interface, obviating the need for complex molding techniques or assembly. Moreover, in the future, by bringing new classes of customized materials and functionalities into 3D printing, multi-material 3D printers can directly fabricate four-dimensional (4D) actuators – which are new breeds of robotics actuators that can be stimuli-responsive, self-morphing, and with embedded programmable architectures.

The CAS-HK Joint Laboratory on Robotics proposes to acquire the DragonFly 2020 Pro 3D electronic printing system in order to perform leading-edge research in developing next generation 3D sensing systems and 4D robotics actuators. We will also modify the system so that advanced sensing and conducting materials (such as graphene oxide, carbon nanotubes, and other nanomaterials) can also be embedded into 3D fabricated mechanical structures in the future. These nanomaterials are usually contained in liquid solutions and which can only be fabricated using traditional MEMS (Microelectromechanical Systems) fabrication techniques such as lithography and etching. However, with the ability of 3D direct printing and curving of these materials, the prototyping and development cost for sensing/electronic devices will be much lower and faster.

Our team will set up the DragonFly 3D printing system at the City University of Hong Kong (CityU) and initially share the usage of the equipment with joint laboratory members from the Shenyang Institute of Automation. After we have ensured the stable operability of the system and finalized the operational procedures (including safety guidelines), we will eventually share the system with other researchers at CityU and other sister institutions in Hong Kong. By the end of the two-year project period, we will also demonstrate several integrated sensing and actuation devices fabricated by the DragonFly system: 1) injectable "motion pills" for tracking mice motions; 2) integrated antenna for cyber physical spherical robots; c) cell-electric-stimulation array for bio-syncretic robots; d) bio-syncretic cell-based actuators.


3D Printing of Miniature Robots for Minimally Invasive Ophthalmological Treatment
Joint Laboratory: SIAT-CUHK Joint Laboratory of Robotics and Intelligent Systems
Project Coordinator: Prof Li Zhang (CUHK)

Abstract
Miniature robots with milli-/micro-/nanoscale sizes, controlled mobility and versatile functionalities emerge as a promising approach for minimally invasive medicine, such as targeted therapy and microsurgery. To actuate and steer the motion of miniature robots, various strategies have been developed, among which, magnetic field is one of the most promising tools for in vivo biomedical applications, because low-strength magnetic field is considered harmless to biological cells and tissue, and remote actuation of miniature robots with multiple degrees of freedom and high precision can be realized in a controllable fashion. To date, although magnetic miniature robots have been studied extensively with the development of top-down and bottom-up fabrication technologies, how to design and fabricate them with a reasonable scale and resolution, as well as diverse materials in a harmless and inexpensive way for specific medical applications in still remains a big challenge.

In this project, the overall objective is to develop a 3D printing strategy which can fully meet the requirements of miniature medical robots for their practical applications in ophthalmological treatment. With the joint efforts from the Department of Ophthalmology and Visual Sciences, Faculty of Medicine, at CUHK, we propose a 3D printing approach to efficiently fabricate diverse miniature robots with a focus on their clinic applications for minimally invasive ophthalmological treatment. The 3D printed miniature robots will have tunable designs consisting of biocompatible and/or biodegradable materials with multi functionalities for conducting tasks. We also expect to develop a magnetic actuation system which is applicable to be integrated with a clinic imaging modality for the operation with human head, thus allowing us to track and control the motion of miniature robots in nasolacrimal duct and an eye ball. After the feasibility studies using ex vivo and animal models, we expect to establish feasible protocols with the medical doctor partners to apply the miniature robots for ophthalmological treatments by using the new technology and the system. Overall, nine research projects are directly related to the 3D printer, a key equipment for this joint laboratory.

We envision that the proposed joint lab researches will pave the way for realizing the practical applications of miniature robots in ophthalmological treatment. The advanced technology and the outcomes from this project will make a significant contribution to Hong Kong and mainland China, particularly in the emerging technology development for medical robotics and minimally invasive therapy.


An Inductively Coupled Plasma Etching System for Compound Semiconductors
Joint Laboratory: Joint Laboratory of Microelectronics
Project Coordinator: Prof Andrew W O Poon (HKUST)

Abstract
The Joint Laboratory of Microelectronics between the Nanosystem Fabrication Facility (NFF) of the Hong Kong University of Science and Technology (HKUST) and the Institute of Microelectronics of the Chinese Academy of Sciences (IMECAS) is applying for a state-of-the-art R&D-grade inductively coupled plasma (ICP) etching system for compound semiconductors. The acquisition and installation of the equipment will significantly enhance the Joint Laboratory's capability in processing technologically relevant compound semiconductors including materials based on gallium nitride (GaN), gallium arsenide (GaAs), indium phosphide (InP) and indium antimonide (InSb). The upgraded infrastructure will bring considerable benefits to academic researchers and industries in semiconductor microelectronics/photonics in Hong Kong and the Guangdong-Hong Kong-Macau Greater Bay Area (GBA), and will complement the infrastructure at the IMECAS in Beijing nicely.

Compound semiconductors, specifically III-V compound semiconductors, have a wide range of material compositions, bandgap energies and material properties. They are often the materials of choice for diverse technological applications including high-power electronic devices, high-frequency devices, light-emitting diodes (LEDs), laser sources, optical amplifiers, optical switches and modulators, photodetectors, and emergent integrated quantum light sources. They constitute core technologies that promise to shape the modern era and beyond, with major societal relevance to energy-efficient systems, next-generation information technology and communications, artificial intelligence (AI), solid-state sensing for automation and environmental monitoring, and futuristic quantum technologies. These devices are lightweight and compact in size, have no moving parts, can be heterogeneously integrated into micro-/nano-systems and are potentially cost-effective when manufactured on a wafer scale.

An integral process step is to transfer device patterns to the compound semiconductor by dry etching. The proposed ICP etching system for compound semiconductors is able to meet various demanding process requirements for the aforementioned applications. The equipment features a high etching rate, a large aspect ratio, a high etching selectivity and a small sidewall roughness. We will operate the new equipment in parallel with the existing, 18-year-old ICP etcher for compound semiconductors that is housed in the NFF cleanroom. This will allow different materials to be separately processed using the two etchers, thus minimizing cross-contamination. We will be able to push the research frontiers and pursue the innovative work outlined in this proposal in a more effective and reliable manner, which would be extremely difficult using only our existing aging equipment. The proposed equipment will also further stimulate research collaborations between Hong Kong and the CAS.


A Small Indoor Mesocosm Facility for Investigating the Impact of Environmental Stressors on Marine Organisms
Joint Laboratory: Sanya Joint Laboratory of Marine Science Research
Project Coordinator: Prof Pei-yuan Qian (HKUST)

Abstract
Coral reefs foster marine lives. However, these rainforests of the sea are declining rapidly in recent years due to global warming, overfishing, ocean acidification, among other things. Coral-associated microbes are indispensable to coral reef ecosystems. Algae provide coral hosts with oxygen via photosynthesis in a symbiotic relationship. Some coral-associated bacteria can help with the energy cycle in coral reef ecosystems and defend the hosts against pathogens. Hong Kong corals live in marginal environments and according to previous research, they are highly adaptable. Over the last five years, we have been collaborating with Prof. Hui HUANG in the South China Sea Institute of Oceanography and Prof. Qiang XIE in the Institute of Deep-Sea Science and Engineering at the CAS to study coral symbiosis in the South China Sea. This joint laboratory was supported by the NSFC-Guangdong Key Project and the performance of the collaborative project was rated "Excellent" by the NSFC. Here we propose to extend our collaboration by focusing on the molecular mechanisms governing the adaptation to environmental stressors of coral species from different geographical regions. To this end, we will first need to set up a small mesocosm facility in the Coastal Marine Laboratory (CML) of the HKUST, taking full advantage of the excellent flow-through seawater system already in place. A similar facility that was set up at the Sanya joint laboratory but was destroyed by a typhoon last fall will be rebuilt soon with funds from the mainland. To test the efficiency of the proposed facility, we will carry out parallel studies in both Hong Kong and Sanya with congeneric coral species from the South China Sea and Hong Kong. The small mesocosm facility at the CML will also enable studying the impact of environmental stressors (particularly temperature and CO2) on other marine organisms in Hong Kong. Using this mesocosm facility, marine scientists in Hong Kong will be able to conduct experiments under controlled conditions in future to bridge the gap between the laboratory and the real world (field observations) in terms of the development, changes, and function of coral symbiosis.


A Technology R & D Platform for the Development and Evaluation of Bioactive Biomaterials for Ageing Osteoporotic Bone Fractures Treatment
Joint Laboratory: The Joint Laboratory for Biomaterials of SIAT-HKU-CUHK
Project Coordinator: Prof Weijia William Lu (HKU)

Abstract
The world's population is ageing. Over 60-years-old people will occupy 22% of the world's population by 2050. According to the Hong Kong Census and Statistics Department, people aged 65 or above will rise significantly from 15% to 36% by 2064. The incidence of osteoporosis, which is closely associated with aging, often leads to bone fractures. Substantial costs are involved in surgeries and subsequent rehabilitations for patients suffering from osteoporotic bone fractures. The annual healthcare costs for osteoporotic fracture in the US were $17 billion in 2005 while the annual hospital expenditure for hip fracture in Hong Kong amounted to $52 million in 2017, which will continue to rise in the next 10-20 years. These costs impose huge socioeconomic and healthcare burden to the patient, family, healthcare system and worldwide society.

Hence, our team (The Joint Laboratory for Biomaterials of SIAT-HKU-CUHK) has mostly focused on the research and development of bioactive biomaterials for the treatment of osteoporotic bone fractures during the last decade. Our team is honored as 'excellent' by the Chinese Academy of Sciences in 2018 due to the production of high impact results as we closely collaborated with the joint laboratory. To make further achievement on functional bone regeneration in osteoporosis, we are aiming to: 1) set up a technology R & D platform for the development and evaluation of bioactive biomaterials for the treatment of ageing osteoporotic bone fractures; 2) investigate the treatment’s efficacy of biomaterials in animal models with CT Bone Mineral Analysis system; 3) prepare for the further clinical trials and product of CT Bone Mineral Analysis system registration using the collected animal data; 4) to serve the collaborators in Guangdong-Hong Kong-Macau Greater Bay Area.

This R & D platform will exploit the synergy between our research expertise and resources in order to achieve our goals. We will focus not only on high quality scientific research but more importantly, on the R&D of effective treatment strategies for achieving functional bone regeneration in osteoporotic patients. Ultimately, our functional biomaterials and treatment protocols will benefit patients and the society with significant reduction on socioeconomic and healthcare burden both locally and internationally.


Shortwave Infrared (SWIR) Imaging and Spectroscopy System for Biomedical Research
Joint Laboratory: Joint Laboratory of Nano-organic Functional Materials and Devices
Project Coordinator: Prof Chun-sing Lee (CityU)

Abstract
Fluorescence bioimaging is a powerful, non-invasive, non-ionizing, and non-destructive technique that allows qualitatively diagnosis, anchoring and disease monitoring, in particular tumors. Nevertheless, this conventional technique is limited to thin samples or superficial tissue (~ 1 mm). Optical focusing on deep cells and tissues (centimeter-scaled) is difficult due to a limited penetration depth of the UV-visible-NIR wavelengths (i.e. 250 - 900 nm). It has been shown that over 100 folds of resolution enhancement can be achieved for tissues in centimeter depths using fluorescence in the shortwave infrared (SWIR) region (i.e. 900 - 1700 nm). However, high performance fluorescence probe working in this region are far more scarce comparing to UV-visible-NIR probes. Other than the challenging tasks of design and synthesis of the SWIR probes, another difficulty is the very limited availability of in vivo characterization tools for such probes. The proposed SWIR imaging facility is not available in Hong Kong and there are less than 10 sets in China (our web search cannot locate any in Beijing). It is thus highly desirable to develop a SWIR fluorescence bioimaging and spectroscopy system for high-resolution imaging on deep cells and tissues in Hong Kong. This system will not only support research of the joint laboratory, and will also benefit other Hong Kong researchers in the area of biomedical imaging.

With our multi-disciplinary expertise, the CityU-TIPC research team target to utilize the proposed system for characterizing and developing SWIR probes with high quantum yield for high-resolution in-vivo monitoring/diagnosis of cancer issues, immune reaction etc. In the long run, this SWIR imaging and spectroscopy system will be one important characterizing instrument in HK for researchers requiring high-resolution bioimaging for deep cells, tissues, small animal, etc.


Isotope Substitution to Enable Precise Structure Determination at China Spallation Neutron Source
Joint Laboratory: IHEP-CityU Joint Laboratory on Neutron Scattering
Project Coordinator: Prof Xun-li Wang (CityU)

Abstract
As one of the largest national scientific facilities, China Spallation Neutron Source (CSNS) in Dongguan, about 70 km north of Hong Kong, is designed to be a world-class research hub for multi-disciplinary research including physics, chemistry, biology, materials science, and materials engineering. Positioned in the same Guangdong-Hong Kong-Macao Greater Bay Area, Hong Kong science community is a direct beneficiary of the powerful CSNS. On the other hand, as CSNS aims to transition from a construction project to a scientifically productive facility, active participation by Hong Kong’s scientific community, with strong tradition in materials science and biomedical science, is also essential.

This proposal is set to enhance the research infrastructure of Hong Kong laboratories to utilize the state-of-the-art neutron source at CSNS. We plan to take advantage of a unique feature of neutron scattering – the sensitivity to isotopes by using isotope substitution to enable precise structure determination. By utilizing the large contrast of neutron scattering lengths with isotopes, neutron scattering could provide unprecedented structural insights than what have been possible with other techniques. For example, in complex organic materials made of light atoms that are difficult to distinguish by conventional methods such as X-ray scattering or electron microscopy, isotope substitution may be employed to label a particular atom or molecule to enhance the scattering contrast, to allow precise identification and structural arrangement.

Three beamlines at CSNS are now open to users: a general purpose powder diffractometer (GPPD) for crystallography and materials science studies, a small angle neutron scattering (SANS) instrument for large scale structures such as polymers and biomolecules, and a neutron reflectometer for thin films and membranes. Based on the functions of these three beamlines, we propose to study the following technologically important materials: 1) High entropy alloys; 2) Bulk metallic glass; 3) Organic photovoltaic materials; 4) Perovskite halide materials. The measurements, with isotope substituted samples, are unique and will showcase the utility of neutron scattering and CSNS.

Successful implementation of this proposal will lead to the establishment of a sample isotope labelling platform for functional materials, the development of basic neutron scattering data analysis schemes and the training of experienced neutron users. More importantly, it will demonstrate the capability of CSNS to potential Hong Kong users, promoting the growth of a vibrant neutron scattering user community in Hong Kong.


Strengthening Thin Film Solar Cell Research: Facility Upgrade and Research Enhancement in Cu-based Chalcopyrite and Kesterite Solar Cells
Joint Laboratory: Joint Laboratory for Photovoltaic and Solar Energy
Project Coordinator: Prof Xudong Xiao (CUHK)

Abstract
Chalcopyrite and kesterite based semiconductors, with Cu(In,Ga)Se2 (CIGS) and Cu2ZnSnS4 (CZTS) as their representatives, are important candidates for photovoltaic solar cells because they possess appropriate bandgap, are strong light absorbers, and demonstrate superior stability at working temperature comparing with many other solar cell materials, e.g., perovskite. They can be produced not only in thin film form but also on flexible substrates that are light and rollable. The current energy conversion efficiency record for CIGS is 23.35%, higher than the record of multicrystalline silicon solar cells. The conversion efficiency for CZTS is about 11%. The biggest bottle necks for improving CZTS material are the detrimental secondary phases induced by the concentration fluctuation of metallic elements. While the performance of CIGS solar cell is already sound, important developments on surface treatments, bulk composition gradient engineering, and bulk defect controls remain extremely active. Continuous efforts are crucially needed to further improve their performances.

Confucius said, “工欲善其事, 必先利其器” (To do a good job, one must first sharpen one's tools). To implement the new approaches for CIGS and CZTS solar cells, we have to strengthen the infrastructure in our laboratory, which were mostly built up a decade ago. Only with appropriate facilities, can the capability and the controllability of the absorber layer growth and device fabrication be achieved.

In this project, we propose to: (1) upgrade the fabrication systems with an electron impact emission spectroscopy (EIES) system to in situ monitor the deposition rate of selected elements, and (2) add a number of high temperature crucibles to increase the capability of depositing materials that can modify the absorber bulk and surface.

With the addition of EIES to our growth system, both CIGS and CZTS absorber layers will be synthesized with higher composition accuracy, higher reproducibility, and higher productivity; With the addition of crucibles, we will be able to deposit KF, RbF, or CsF for CIGS surface modification and for CZTS grain boundary passivation, and deposit Ag for CIGS bulk modification to adapt new ideas for large bandgap CIGS formation.


Upgrading of Laser Ablation - Multiple Collector - Inductively Coupled Plasma - Mass Spectrometer (LA-MC-ICP-MS) for Simultaneous Measurement of U/Pb and Hf Isotopes
Joint Laboratory: Joint Laboratory of Chemical Geodynamics
Project Coordinator: Prof Min Sun (HKU)

Abstract
Because of the resistance to weathering/alteration and relative high contents of U and Hf, zircon is the most useful mineral for isotopic age dating and geochemical tracer to study magma source, mantle processes, crustal growth, and paleo-continental reconstruction. At the present, U/Pb and Lu/Hf isotopes are measured separately on different laser ablation spots. However, the tiny zircon minerals (<100 micron) are mostly not homogeneous (especially metamorphic zircons), i.e. different parts may have different petrogenesis. Therefore, U/Pb age and Hf isotopic compositions from different analytical spots may give misleading interpretations.. This proposed project will allow us to establish a new technique of laser ablation split stream so that the same sample volume can be analyzed for U/Pb and Hf isotope compositions simultaneously. This will place our Joint Laboratory of Chemical Geodynamics between HKU and CAS at a forefront position.


Photo-Functional Molecules and Materials. Photophysics, Photo-Catalysis and Renewable Energy Schemes
Joint Laboratory: Joint Laboratory on New Materials
Project Coordinator: Prof Chi-ming Che (HKU)

Abstract
The mission of the HKU-CAS Joint Laboratory on New Materials is to engage in research on new photo-functional molecules and compounds for light-to-chemical energy conversion reactions, photochemical devices, and materials science. The research programs entail synthetic chemistry, photochemistry and excited state dynamics, all of which involve systems ranging from macromolecular light-emitting polymers to organic light-harvesting molecules to bioorganic-inorganic catalytic interfaces. With new investigators from HKU, the scope of investigations will expand to include supramolecular inorganic-organic hybrid systems, heterogeneous photo-catalysis and photochemical devices.

Through cross-disciplinary research, new classes of luminescent materials with tailored opto-electronic properties and photo-physical functionalities will be developed for applications including light-to-chemical energy conversion and sensing. We will conduct fundamental research exploring the mechanism of how catalysts and catalytic surfaces capture light to drive difficult yet selective chemical reactions. With the use of ultrafast time-resolved absorption and emission spectroscopies to be established through this proposal application, we would examine the dynamics and reactivity of the photo-generated short-lived reactive species. Another initiative of the Laboratory will focus on examining the excited state evolution of new materials including that of earth-abundant transition metal complexes, organic-inorganic hybrid colloids, and hybrid bilayer membranes. The information on how their excited states are affected by factors such as solvent polarity and substrates are instrumental to the design of new materials with properties suitable for use in energy-related applications. Studies will also be extended to developing new forms of materials such as supramolecular polymeric systems and nano/micro-swimmers. These efforts may result in practical outcomes including applications to generate and store intermittent renewable energy sources in the form of easily-transportable fuels from the direct utilization of the electronic excited states or high-energy charged pairs generated using solar energy to power societies in a sustainable manner.

The Laboratory has proven capabilities in the area of highly efficient phosphorescent materials and will bring in new expertise in designing uniquely functionalized metal-organic layered motifs and novel electrode materials for practical applications in green chemical power sources. The synergy between synthetic chemistry and materials science will propel the University of Hong Kong and the Chinese Academy of Sciences to turn inventive ideas into reality and lead technological advancement in the global stage.