Yu Han

All Publications

• Freestanding Ordered Intermetallic Nanomembranes Released from Etchable Oxide Templates. Journal of the American Chemical Society Wang, J., Cui, Y., Blake, E., Li, J., Wei, X., Khandelwal, A., Hoogendoorn, L., Yu, Y., Theuss, F., Han, Y., Wang, T. C., Zhang, G., Wu, Y., Barnum, A., Hart, P., Thampy, V., Cui, Y., Hwang, H. Y. 2026

  Abstract

  Intermetallic compounds exhibit long-range atomic ordering that endows them with physicochemical properties distinct from those of elemental metals and disordered alloys. Extending ordered intermetallics into ultrathin, freestanding geometries is of both fundamental and technological interest, yet it remains challenging because the high temperatures required for chemical ordering exceed the thermal stability of conventional sacrificial templates. Here, we introduce water-etchable aluminate oxides as lattice-matched, thermally robust sacrificial templates for the epitaxial growth and nondestructive release of intermetallic nanomembranes. Using Pt3Sn as a model system, we realize millimeter-scale freestanding membranes that preserve long-range chemical order and crystallographic orientation after being released. These nanomembranes maintain structural integrity and mechanical robustness during transfer and under mechanical loading, demonstrating their compatibility with flexible device architectures. Low-temperature magnetotransport measurements further reveal the preservation of quantum interference and multiband transport behaviors. This oxide template strategy establishes a generalizable synthetic pathway toward freestanding intermetallic nanomembranes and other ultrathin metal systems.

  View details for DOI 10.1021/jacs.6c06492

  View details for PubMedID 42290513

• Asymmetric pathways for lithium extraction and recovery based on the two-phase equilibrium of layered oxides. Nature communications Hill, G. T., Stone, R., Han, Y., Liu, J., Zou, S., Zhou, H., Liu, C. 2026

  Abstract

  Electrochemical intercalation offers a promising platform for Li+ extraction. However, only limited types of electrode materials have been investigated. The challenge to broaden and tailor materials for electrochemical intercalation-based Li+ extraction lies in the lack of understanding of material's response upon co-intercalation of multiple ions, therefore, paired process design to enable reversible Li+ extraction and recovery. Here, we showcase the design of asymmetric ion pathways for Li+ extraction and recovery for host material with complex Li+ and Na+ interaction using layered cobalt oxide as a model material. The two-phase equilibrium of Na0.48CoO2 and Li0.94CoO2 governs Li+ selectivity when a high depth of intercalation is achieved (low vacancy level). We show that the relative rate between ion exchange and intercalation is critical to determine the ion pathways. The relationship can be quantitatively compared using the average pseudo ion exchange rate (CpseudoIX) and the intercalation rate (Cinter). The ion pathways at the three regimes with CpseudoIX > Cinter, CpseudoIX ~ Cinter, and CpseudoIX

  View details for DOI 10.1038/s41467-026-72755-4

  View details for PubMedID 42103713

• Selectivity mechanisms of ion intercalation in Prussian blue analogs MATTER Sun, L., Zou, S., Yan, G., Han, Y., Suresh, A., Bera, M., Tirrell, M., Liu, C. 2026; 9 (3)

  View details for DOI 10.1016/j.matt.2025.102575

  View details for Web of Science ID 001710296700001

• Room-temperature charge localization in ion-coupled bilayer transistors SCIENCE Gao, M., Hong, H., Fan, S., Chowdhury, T., Naqvi, Z., Ge, J., Liang, C., Han, Y., Guisinger, N. P., Qiu, Y., Kim, D., Vaikuntanathan, S., Liu, C., Park, J. 2025; 390 (6771): 356-360

  Abstract

  Controlling the localization of mobile charges in solids enables the discovery of correlated physical phenomena, but applying it for the development of next-generation electronics requires achieving such control under practical conditions. In this study, we report room-temperature, switchable charge localization in high-quality bilayer transistors that comprise a monolayer of molecular crystal on top of a monolayer semiconductor. By using an ion gate, we selectively populated either localized molecular states or semiconductor band states, achieving complete localization from mobile charges at densities up to 3 × 1013 per square centimeter. This transition was energetically stabilized by the formation of coupled electron-ion dipoles, which could be tuned through Coulomb engineering. These properties further enabled single-band ambipolar transistor operation without substitutional dopants, demonstrating the potential of electron-ion correlations for practical electronic applications.

  View details for DOI 10.1126/science.ady7969

  View details for Web of Science ID 001602616000021

  View details for PubMedID 41129645

• Distributed direct air capture by carbon nanofiber air filters SCIENCE ADVANCES Wu, R., Delgado, H. E., Xie, Y., Chen, Y., Yan, G., Luo, E., Li, Q., Fan, Q., Han, Y., Higueros, G. M., Ruthen, A., Sui, C., Suresh, A., Mitzi, D. B., Liu, C., Elgowainy, A., Hsu, P. 2025; 11 (42): eadv6846

  Abstract

  The rising atmospheric CO2 concentration is one of the biggest challenges human civilization faces. Direct air capture (DAC) that removes CO2 from the atmosphere provides great potential in carbon neutralization. However, the massive land use and capital investment of centralized DAC plants and the energy-intensive process of adsorbent regeneration limit its wide employment. We develop a distributed carbon nanofiber (CNF)-based DAC air filter capable of adsorbing CO2 downstream in ventilation systems. The DAC air filter not only has the potential to remove 596 MtCO2 year-1 globally but can also decrease energy consumption in existing building systems. The CNF-based adsorbent has a capacity of 4 mmol/g and can be regenerated via solar thermal or electrothermal methods with low carbon footprints. Through life cycle assessment, the CNF air filter shows a carbon removal efficiency of 92.1% from cradle to grave. Additionally, techno-economic analysis estimates a cost of $209 to 668 in capturing and storing 1 tonne of CO2 from direct air.

  View details for DOI 10.1126/sciadv.adv6846

  View details for Web of Science ID 001596837700018

  View details for PubMedID 41105774

  View details for PubMedCentralID PMC12533599

• Cooperative and inhibitory ion transport in functionalized angstrom-scale two-dimensional channels NATURE COMMUNICATIONS Wang, M., Xiong, Q., Yue, X., Yan, G., Han, Y., Lyu, Z., Li, Z., Sun, L., Hoenig, E., Xu, K., Lewis, N. H. C., Merz Jr, K. M., Chen, Q., Schatz, G. C., Liu, C. 2025; 16 (1): 5854

  Abstract

  Significant success has been achieved in fabricating angstrom-scale artificial solid ionic channels aiming to replicate the biological ion channels (BICs). Besides high selectivity, BICs also exhibit sophisticated ion gating and interplay. However, such behavior and functionality are seldomly recreated in the artificial counterparts due to the insufficient understanding of the molecular origin. Here we report cooperative and inhibitory ion transport in angstrom-scale acetate functionalized MoS2 two-dimensional channels. For cooperative ion transport, the permeability of K+ is doubled in the presence of only 1% Pb2+ (versus K+ by molarity), while the permeability of Pb2+ is independent of K+. Molecular dynamics simulations reveal complex interplay among K+, Pb2+, and the anions in governing the cooperativity, such that Pb2+ ions capture and slow down the anions via long-range interaction, which leads to the synchronization of anions with K+ to transport as ion pairs with reduced interaction with the channel surface. For inhibitory ion transport, divalent Co2+ (or Ba2+) and Pb2+ can replace each other in the confined channel and compete for the limited transport cross section. Our work reveals ion transport phenomena in extreme confinement and highlights the potential of manipulating ion interplay in confinement for achieving advanced functionalities.

  View details for DOI 10.1038/s41467-025-61307-x

  View details for Web of Science ID 001523451600005

  View details for PubMedID 40595648

  View details for PubMedCentralID PMC12216153