Project Supervisor:
Professor Nicholas Fang - Hong Kong University
Background:
Electrochemical conversion of CO2 into usable fuels and chemicals is a game-changing strategy to mitigate climate change, as it effectively turns waste emissions into valuable economic assets. However, a major bottleneck in making CO2 battery systems commercially viable is the design of the electrodes. We need them to maximise efficiency and last a long time, which requires precise control over the local environments in which the reactions occur.
While the chemical composition of Nickel and Cobalt electrocatalysts has been heavily studied, the role of their physical structure (morphology) remains vastly under-quantified in CO2 battery systems. Changes in surface roughness, density and crystalline structure directly alter surface area, conductivity, and reaction kinetics. This project steps into that gap to experimentally see how variations in fabrication parameters dictate electrode and battery performance.
Objectives:
1. Investigate performance correlatives: Quantify exactly how changes in electrode surface shapes alter electrochemical outputs i.e. voltage, current density, and power.
2. Find the best testing settings: Identify the ideal combination of current, time, temperature, and stirring speed needed to create electrodes that are both highly active and stable over time.
Methodology and Limitations:
I will be carrying out a series of laboratory experiments over a 3-week period to create and test different electrodes under different conditions.
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Making the Baseline Electrodes: I will first create standard Nickel-Cobalt electrodes using a set chemical solution at standard laboratory settings (stirred at 350 rpm at 80°C) to act as my comparison baseline.
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Changing the Test Settings: I will then systematically change one deposition parameter at a time to see how it affects the electrode's physical shape:
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Current Density: Testing low electrical currents against high electrical currents.
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Deposition Time: Comparing short coating times (thin, patchy layers) against longer coating times.
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Stirring Speed: Testing how fast the liquid is mixed (low, moderate, and high RPMs).
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Bath Temperature: Testing how the temperature of the liquid bath (60°C vs 80°C) changes the result.
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Testing & Characterisation: Finally, I will measure the voltage of each electrode to see how well it performs and look at its surface structure using available lab equipment.
Project Realities & Limitations: Because I only have 3 weeks of hands-on lab time, I can only test a maximum of 6–10 different variations, and I won't have time to repeat the experiments to double-check for anomalies. Additionally, these small lab-scale tests are just a starting point and might behave differently when scaled up to big industrial systems.
Outputs and Impact:
The main output of this project will be a clear dataset showing exactly how making small adjustments in the lab changes the final structure and efficiency of the electrodes.
By finding the recipe for the most efficient electrode design, this work helps bring us one step closer to making large-scale CO2 batteries a reality. Ultimately, this supports global net zero goals by proving we can trap harmful carbon emissions and turn them directly into useful, clean energy.
Motivation:
Studying Civil Engineering has made me realise how important green infrastructure and clean energy systems are for the future of our cities. I chose this project because it bridges the gap between material design and environmental sustainability. Working on optimising these electrodes gives me a hands-on opportunity to see how laboratory research can directly impact real-world engineering solutions and help us build cleaner infrastructure.