Improving graphene for energy applications
Dr Zhaojun Han was attracted to UNSW by the University’s strong reputation in the energy field, and officially joined the University in early 2019. His unique appointment allows him to split his time between the School of Chemical Engineering and the School of Mechanical and Manufacturing Engineering at UNSW, as well as continuing his role as Senior Research Scientist at CSIRO Manufacturing, Lindfield.
“I have greatly enjoyed working at CSIRO for the last 10 years, where the focus has been on industry and technology applications, but I wanted to create opportunities to explore some of the more pressing questions in my field,” says Han.
He says joining UNSW seemed the perfect next step. “Not only are my research interests in materials and energy devices well-aligned with the Faculty of Engineering’s strategic focus on advanced energy technologies, but I am also keen on teaching and engaging with students,”
he continues. This is why he, supported by both UNSW and CSIRO colleagues, is now helping build a CSIRO-UNSW Joint Laboratory to facilitate research collaborations across the two organisations and increase the exposure of students to industry and start-up companies.
“My strong belief is that renewable energy is set to significantly impact the current energy mix, and it’s essential to promote energy research to the next generation of Australian researchers as well as train large numbers of up-and-coming engineers to be leaders in this field.”
With a strong interest in developing nanomaterials for energy storage devices, electrochemistry, and catalysts for hydrogen generation, Han’s work explores vital questions. He says the wonder material graphene is a likely answer to many of them.
For many years, graphene has been generating considerable excitement and traction in the scientific community due to its excellent properties. It is 200 times stronger than steel, is flexible and can conduct electricity more efficiently than copper. According to Han these qualities make it a highly versatile material that can be engineered into many different multifunctional structures.
“It is a truly fascinating material. I have worked on other materials before, for example, carbon nanotubes and metal oxides, but graphene is unique,” he says.
In one project, in collaboration with Scientia Professor Rose Amal in the Particles and Catalysis Research Laboratory (PartCat), Han has developed a special form of graphene as a support for catalytic reactions, specifically for the generation of hydrogen energy.
“We are using a vertical graphene structure where the nanosheets are oriented vertically on the substrate surface. This is different from conventional graphene flakes which usually have a random orientation. Vertical graphene is an open, three-dimensional structure, and we are using a variety of techniques to characterise and understand the reaction process and mechanical properties,” he explains.
“I think our unique vertical graphene structure is going to make a significant impact in many different fields. We have some great momenta, which is why I’m advocating for it so strongly,” he says.
Commercialisation is a key aim with this project and Han says it is on the near horizon. “We’re developing the IP and, once it’s ready, and we’ve found suitable collaborators or customers keen to uptake the technology, we’ll scale up the production.”
In another project, in collaboration with Professor Chun Hui Wang from Mechanical Engineering,Han is exploring the potential of creating multifunctional energy storage devices.
“Most supercapacitors or batteries serve only one purpose: energy storage. We’re looking to create a device using carbon-based materials that can provide both mechanical support and energy storage for vehicles such as drones, aeroplanes or trains,” he says.
Han is also working on a fundamental project to better understand ion transport. “We know that when you change the nanostructure of the electrode, interactions between ion and ion, or ion with solvent, or the ion with the electrode itself can be affected,” he explains.
“Using a special electrode made of graphene, for example, means ion transport could be fast in all two-layered graphene structures due to the quantum confinement effect, compared to other electrode materials such as activated carbon which has a very random structure.”
Outside of UNSW, Han is a Scout leader and says that he takes the opportunity to share his passion for science to all the young boys and girls in his care.
“We do all sorts of games that include science experiments. As the other leader in our group is also a renowned scientist, we always try to put some science into the Scouts and raise awareness about how exciting the subject can be,” he says.
Dr Zhaojun Han can be contacted via email Zhaojun.firstname.lastname@example.org and has an office in the new Science and Engineering Building, Level 5, Room 519
Written by: Penny Jones