Graphene, a new material exhibiting outstanding thermal conductivity, has attracted attention as a filler for next-generation heat-dissipation composite materials. A Jeonbuk National University (JBNU) undergraduate student has attracted notice for demonstrating through research that expanding the lateral size of graphene platelets can reduce the thermal resistance of composite materials.

The student at the center of the story is Nam Hae-eun, a fourth-year student in the JBNU Department of Organic Materials and Textile Engineering, supervised by Professor Kim Seong-ryun. Nam recently had the research results published as the paper "Thermal percolation behavior in thermal conductivity of polymer nanocomposite with lateral size of graphene nanoplatelet" in the SCI-level international journal Polymers (IF: 4.329). Jang Ji-woon, a PhD candidate in the Department of Organic Nanoengineering at Hanyang University, supervised by Professor Kim Seong-hoon, participated as a co-author.

Having committed to research, Nam has worked as an undergraduate researcher in JBNU's composite materials research laboratory since her second year. She focused her research on reducing interfacial thermal resistance (ITR), a factor that decreases thermal conductivity in composite materials.

To reduce the thermal resistance of composites, she focused on the new material graphene. Through various experiments, she demonstrated that by expanding the lateral size of graphene platelets, thermal resistance can be reduced, thereby increasing the thermal conductivity of composites.

The thermal conductivity of the investigated composites was analyzed by applying Nan’s model before percolation and the Percolation model after percolation, respectively.

Nam said, "I am very pleased to have achieved good results after working as an undergraduate researcher since the winter break of my second year. I am grateful to my supervisor, the Jeonnam Talent Lifelong Education Promotion Foundation, and my parents for supporting the research." She added, "The experience as an undergraduate researcher was a valuable opportunity to conduct research prior to graduate school and to plan not only my knowledge but also my personal values and goals. I hope other students will take on challenges with an open mind."

Supervisor Professor Kim Seong-ryun said, "By mentoring undergraduate researchers, I wanted to instill confidence in students that by faithfully completing the university curriculum and departmental requirements and by doing their best to develop research skills, they can grow into experts in their field." He added, "I would like to commend Nam Hae-eun for her efforts in balancing two years of undergraduate studies and laboratory work to achieve excellent research outcomes."

This research was carried out with support from the National Research Foundation of Korea.