Welcome to Dr. Jiuhui Han's research site

Dr. Jiuhui Han is currently an assistant professor and prominent research fellow at the Frontier Research Institute for Interdisciplinary Sciences (FRIS), Tohoku University. He received his Ph.D. in Materials Science from Tohoku University in 2017. His research focuses on the development and characterization of advanced nanoporous materials for energy-oriented applications.

The keywords of our research:

Nanoporous materials
Graphene
Dealloying
Materials corrosion
Electrochemistry
Energy storage and conversion
Transmission electron microscopy

Selected research highlights

Nanoporous graphene: New synthetic approach pushes pore size boundaries to mesoscale

Published in Advanced Materials

Vapor phase dealloying: A new universal synthesis of nanoporous materials

Published in Nature Communications

Sodium-ion batteries: Uncovering the charge storage mechanism of hard carbon

Published in Nano Letters

Operando TEM observations: Synergism between catalysts boosts efficiency

Published in Nano Letters

Check more highlights here ...

My research interest

Dealloying is an electrochemical event in which one or more alloy components selectively dissolve into an environment medium from a parent alloy and the remaining component(s) re-organize into a bicontinuous structure through nanoscale interfacial diffusion. The 3D nanoporous materials produced by this technique feature a nanoscale porous microstructure with well-defined topology and large surface-to-volume ratios. Their abundant internal surfaces are easily accessible to electrons from the interconnecting metallic backbones as well as ions/molecules from the coherent open pores, providing a novel platform for charge/energy transfers and catalytic chemical and electrochemical reactions. My research focuses on this unique category of materials and their coupling with electrochemistry, including: (1) the development of new dealloying principles; (2) the development of new nanoporous materials beyond conventional metals; and (3) exploration of surface/interface electrochemistry in these 3D nanoporous platforms with the goal of developing emerging energy conversion and storage technologies such as fuel cells, electrolyzers, and next-generation batteries for a carbon-neutral society. We also incorporate the state-of-the-art in situ/operando transmission electron microscopy (TEM) techniques into our research to study dynamic interfacial phenomena at the atomic scales.

Novel nanoporous materials by dealloying

Emerging electrochemistry for sustainable energy

Interfacial phenomena by in situ transmission electron microscopy

Selected publications

1. J. H. Han, I. Johnson, M. W. Chen*. 3D continuously porous graphene for energy applications. Advanced Materials 2108750 (2022).

2. J. H. Han, G. Huang, Z. L. Wang, J. Du, H. Kashani, M. W. Chen*. Low-temperature carbide-mediated growth of bicontinuous nitrogen-doped mesoporous graphene as an efficient oxygen reduction electrocatalyst. Advanced Materials 30, 1803588 (2018).

3. C. C. Yang^#, J. H. Han^#, P. Liu^#, C. Hou, G. Huang, T. Fujita, A. Hirata, M. W. Chen*. Direct observations of the formation and redox-mediator-assisted decomposition of Li₂O₂ in a liquid-cell Li-O₂ microbattery by scanning transmission electron microscopy. Advanced Materials 29, 1702752 (2017).

4. J. H. Han, I. Johnson, Z. Lu, A. Kudo, M. W. Chen*. Effect of local atomic structure on sodium ion storage in hard amorphous carbon. Nano Letters 21, 6504–6510 (2021).

5. C. Hou^#, J. H. Han^#, P. Liu, G. Huang, M. W. Chen*. Synergetic effect of liquid and solid catalysts on energy efficiency of Li-O₂ battery: cell performances and operando STEM observations. Nano Letters 20, 2183-2190 (2020).

6. J. H. Han^#, C. Li^#, Z. Lu^#, H. Wang, Z. L. Wang, K. Watanabe, M. W. Chen*. Vapor phase dealloying: a versatile approach for fabricating 3D porous materials. Acta Materialia 163, 161-172 (2019).

7. J. H. Han, G. Huang, Y. Ito, X. W. Guo, T. Fujita, P. Liu, A. Hirata, M. W. Chen*. Full performance nanoporous graphene based Li-O₂ batteries through solution phase oxygen reduction and redox-additive mediated Li₂O₂ oxidation. Advanced Energy Materials 7, 1601933 (2017).

8. J. H. Han^#, X. W. Guo^#, Y. Ito, P. Liu, D. Hojo, T. Aida, A. Hirata, T. Fujita, T. Adschiri, H. S. Zhou, M. W. Chen*. Effect of chemical doping on cathodic performance of bicontinuous nanoporous graphene for Li-O₂ batteries. Advanced Energy Materials 6, 1501870 (2016).

9. L. H. Chen^#, J. H. Han^#, Y. Ito, T. Fujita, G. Huang, K. L. Hu, A. Hirata, K. Watanabe, M. W. Chen*. Heavily doped and highly conductive hierarchical nanoporous graphene for electrochemical hydrogen production. Angew. Chem. Int. Ed. 57, 13302-13307 (2018).

10. Z. Lu^#, C. Li^#, J. H. Han^#, F. Zhang, P. Liu, H. Wang, Z. L. Wang, C. Cheng, L. H. Chen, A. Hirata, T. Fujita, J. Erlebacher, M. W. Chen*. Three-dimensional bicontinuous nanoporous materials by vapor phase dealloying. Nature Communications 9, 276 (2018).

11. J. H. Han, Y. C. Lin, L. Y. Chen, Y. C. Tsai, Y. Ito, X. W. Guo, A. Hirata, T. Fujita, M. Esashi, T. Gessner, M. W. Chen*. On-chip micro-pseudocapacitors for ultrahigh energy and power delivery. Advanced Science 2, 1500067 (2015).

12. J. H. Han, A. Hirata, J. Du, Y. Ito, T. Fujita, S. Kohara, T. Ina, M. W. Chen*. Intercalation pseudocapacitance of amorphous titanium dioxide@nanoporous graphene for high-rate and large-capacity energy storage. Nano Energy 49, 354-362 (2018).

13. J. H. Han, H. P. Li, Z. Lu, G. Huang, I. Johnson, K. Watanabe, M. W. Chen*. 3D bimodal porous amorphous carbon with self-similar porosity by low-temperature sequential chemical dealloying. Chemistry of Materials 33, 1013–1021 (2021).

14. Q. Q. Sang, S. Hao, J. H. Han*, Y. Ding*. Dealloyed nanoporous materials for electrochemical energy conversion and storage. EnergyChem 4, 100069 (2022).