Zhu Wanyi

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Young Scholar TechTalk – Next-generation Aqueous Magnesium-ion Batteries

Innovation Wing Two, TechTalk / By

October 8 2024 (Tuesday) 4:30-5:30pm
Aqueous magnesium batteries offer a promising alternative to lithium-ion technology due to their low cost, material abundance, safety, and comparable performance. However, magnesium metal anodes are hindered by passivation, and the narrow electrochemical stability window of aqueous electrolytes significantly limit the battery voltage. My research work introduces innovative aqueous electrolyte systems to address these challenges. A dual-electrolyte magnesium-air battery was developed, achieving a 50% higher peak power density and 46% higher open circuit voltage compared to traditional single-electrolyte systems. Subsequently, a novel water-in-salt electrolyte enabled the first rechargeable aqueous magnesium-ion battery with reversible magnesium metal anode stripping and plating behavior. Furthermore, a quasi-solid-state electrolyte was formulated to regulate ion storage at the cathode, delivering a voltage plateau of 2.6-2.0 V and a remarkable energy density of 264 Wh kg−1, nearly five times higher than current aqueous Mg-ion batteries. This work demonstrates significant advancements in aqueous magnesium batteries, offering a safe and high-performance energy storage solution for a clean energy future.

Young Scholar TechTalk – Ground Characterization from Digital Drilling Data with Time Series Algorithm

Innovation Wing Two, TechTalk / By

July 30 2024 (Tuesday) 4:30-5:30pm
Drilling a hole serves as an in-situ test for assessing geomaterial strength. Digital methods like Measurement While Drilling (MWD) and Drilling Process Monitoring (DPM) have been utilized to record drilling data for ground characterization, offering advantages in data acquisition and cost-effectiveness compared to conventional methods. However, challenges lie in addressing random variations in MWD penetration rates, leading to undesirable correlations with other investigation results. This study aims to address the research gap by analyzing digital drilling data from various projects using a time-series algorithm associated with DPM. The study includes MWD depth-series data from advanced drillholes and blastholes for safe tunnelling, instrumented boreholes for site investigation, and DPM time-series data from scientific drillholes for oil shale exploration. The reliable and accurate interpretation of digital drilling data with time-series algorithm can help MWD method become common and standard method for ground characterization in the geotechnical engineering and petroleum engineering.

HKAES TechTalk – Metallurgical Issues in Water Supplies in Hong Kong

Innovation Wing Two, TechTalk / By

June 26 2024 (Wednesday) 4:00-5:00pm
Water supply in Hong Kong began more than 170 years ago in 1851. Initially, only fresh water was supplied but serious droughts in the 1950s-60s led to the development of one of the world’s first SWFT – “seawater for toilet flushing” systems, which continues today and covers around 85% of the Hong Kong population. This talk will focus on the metallurgical issues encountered in the supply of both fresh and sea water in Hong Kong. For fresh water, excess lead (Pb) was reported in a newly completed housing estate in 2015 and since then, measures have been taken to tighten the control of materials used in pipes and solder joints. Yet, potable-water grade copper-alloy materials allowable by international standards are still not entirely Pb-free, and this talk will report a scientific study on the metallurgical pathways for Pb-leading from such materials. For seawater supply, using the SWTF system for more than 60 years is met with increasingly frequent pipe bursts due to seawater-induced corrosion of the ferrous pipe materials. This talk will report an on-going study on a type of corrosion inhibitors which, if added to the seawater, can potentially lengthen the lifespan of the pipes. The research reported here is supported by the Research Impact Fund of the Hong Kong Research Grants Council and the Water Supplies Department of the HKSAR Government.

TechTalk – Building Functional Devices with Colloidal Nanocrystals from the Bottom Up

Innovation Wing Two, TechTalk / By

June 27, 2024 (Thursday) 4:30-5:30pm
Speaker: Professor Leo Tianshuo Zhao, Assistant Professor, Department of Electrical and Electronic Engineering, Faculty of Engineering, HKU
This talk will highlight our previous works about developing heavy-metal-free NC materials and efficient surface modification for near-infrared optoelectronic devices and advancing scale-up fabrication of NC sensor devices for IoT technologies. The talk will also include our recent work on the nanoprinting of NCs to acheive multi-material and multi-functional devices.

TechTalk – Urban Co-modality: Transforming the Future Collaborative Passenger and Freight Transportation

Innovation Wing Two, TechTalk / By

June 20, 2024 (Thursday) 4:30-5:30pm
Due to the rapid development of the e-commerce market and the surging urban logistics demand, the concept of collaborative passenger and freight transportation in the urban context (urban co-modality) is becoming increasingly popular. Urban co-modality exploits the under-utilized capacity in existing urban multimodal transportation systems. This talk will introduce three types of urban co-modality, namely, co-modality based on public transit systems, individual travelers (crowdshipping), and emerging modular vehicles. In this talk, we first introduce analytical and optimization studies of the co-modality problem based on public transit systems, including quantifying the impacts of introducing co-modality on public transit and urban freight systems, examining the Pareto-improving co-modal system that benefits both users and operators, and designing co-modal service networks. We then present recent studies on crowdshipping – engaging travelers in the crowd to carry freight. The optimal pricing strategies of the crowdshipping platform in alternative business formats are identified. Finally, we discuss prospective opportunities to use modular vehicle-based transit systems for co-modal service. Our studies demonstrate that collaborative passenger and freight transportation is a future trend of sustainable transportation, which has the potential to alleviate congestion, reduce carbon emissions, facilitate urban mobility, and create social benefits for users and operators.