Haiyan Mao

All Publications

• High-Entropy Second Solvation Shell by Anion Diversity for Aqueous Zinc-Ion Electrolytes ACS ENERGY LETTERS Su, H., Hinks, E., Chen, Y., Kim, S., Li, Y., Chi, X., Zhang, P., Wang, J., Choi, I., Mao, H., Huang, I., Xu, X., Chen, Z., Qin, J., Cui, Y. 2026

  View details for DOI 10.1021/acsenergylett.5c04154

  View details for Web of Science ID 001714848400001

• Scalable Carbon Dioxide Capture Using Clay-Derived Zeolites via Atomic Rearrangement. Journal of the American Chemical Society Li, J., Li, J., Fang, S., Lyu, H., Yuan, L., Guan, X., Feng, G., Chi, X., Mao, H., Wu, Y., Li, Y., Liu, Z., Zhang, Z., Catrysse, P., Dionne, J., Fan, S., Cui, Y. 2026

  Abstract

  Effective carbon capture materials are crucial for mitigating climate change and supporting sustainable industrial processes. However, developing scalable, cost-effective adsorbents with high carbon dioxide capacity, superior selectivity, and long-term stability remains a major challenge. Here, we report the scalable synthesis of Linde Type A zeolite via atomic reassembly of halloysite clay using mature industrial processes, achieving a high carbon dioxide adsorption capacity of 5.0 mmol g-1 with good cyclic stability. The transformation from a layered to a cubic framework with enlarged vacant spaces significantly enhances carbon dioxide accommodation. Additionally, the as-prepared zeolite demonstrates outstanding carbon dioxide/nitrogen selectivity (178 for 5% carbon dioxide) and robust thermal stability over multiple adsorption-desorption cycles. In situ tests reveal that adsorption is primarily governed by weakly bound interactions, allowing for the easy regeneration. This study presents a promising and scalable strategy for developing high-performance adsorbents toward gigaton-scale carbon dioxide capture applications.

  View details for DOI 10.1021/jacs.5c20976

  View details for PubMedID 41736194

• Mesh-like structure integrated core-shell-shell nanocomposites for enhanced stability and performance in carbon capture. Nature communications Yang, S., Mao, H., Dun, C., Liu, J., Hou, K., Cai, A., Wang, J., Lee, J. K., Li, D., Lyu, H., Chen, Z., Lv, X., Zhuang, H., Xu, X., Zheng, X., Ren, G., Reimer, J. A., Cui, Y., Urban, J. J. 2025; 16 (1): 10526

  Abstract

  Carbon capture is essential for mitigating climate change, yet most sorbents struggle to combine high capacity with chemical stability. Here we report core-shell-shell (CSS) nanocomposites that integrate adsorption efficiency with exceptional robustness. The design couples a metal-organic framework (MOF) core, which enriches local CO2 concentration, with a polyamine shell that is reorganized into a porous, ordered network through entanglement with an outer covalent organic framework (COF) shell. This hierarchical architecture enables dual amine functionalization via sequential "click" and Schiff-base reactions, achieving a CO2 uptake of 3.4 mmol g-1 at 1 bar. The COF outer layer also acts as a protective barrier, suppressing humidity interference and doubling cycling stability under simulated flue gas. Remarkably, the nanocomposites maintain structural integrity after one week in strongly acidic (3 M HNO3) or basic (NaOH, pH=14) environments, underscoring their chemical resilience. By uniting high capacity, cycling durability, and environmental tolerance, this CSS strategy offers a versatile platform for next-generation carbon capture materials.

  View details for DOI 10.1038/s41467-025-65531-3

  View details for PubMedID 41298365

  View details for PubMedCentralID PMC12658231

• Strain release through hydrogen bond-mediated layer twisting. Science advances Zheng, Q., Li, B., Liu, S., Cao, C., Rimsza, J. M., Zhang, Q., Bai, J., Chang, C., Wang, J., Liang, C., Mao, H., Carbone, M. R., Lu, D., Pyatina, T., Zheng, H. 2025; 11 (44): eady6869

  Abstract

  Strain engineering, enabling the precise control over structure and functional properties, is a key strategy for the design of advanced materials. However, the mechanisms governing strain evolution and release at the nanoscale remain largely unexplored. In this study, we leverage in situ heating transmission electron microscopy and synchrotron x-ray spectroscopy to investigate the strain relaxation pathways of boehmite (γ-AlOOH) at 575 kelvin by revealing real-time structural dynamics. Through tracking the moiré pattern evolution, we identify distinct strain release mechanisms, including layer twisting, defect formation, and domain restructuring. Our neural network potential calculations reveal that energy fluctuations at small twist angles are dominated by an interference-like interaction modulation of hydrogen bonds between boehmite interlayers, with metastable twisted structures corresponding to local minima of the potential energy landscape. This work establishes a previously unidentified paradigm of two-dimensional layer twisting mediated by hydrogen bonding, offering insights into strain-driven transformation mechanisms, and thus may have broad implications for strain in material and earth sciences.

  View details for DOI 10.1126/sciadv.ady6869

  View details for PubMedID 41171909

• Multistep Growth Pathway of Covalent Organic Framework Onion Nanostructures. Journal of the American Chemical Society Zheng, Q., Ren, A., Zagalskaya, A., Mao, H., Lee, D., Yang, C., Bustillo, K. C., Wan, L. F., Pham, T. A., Reimer, J. A., Zhang, J., Liu, Y., Zheng, H. 2024

  Abstract

  The growth of complex organic macromolecular materials in solution is a pervasive phenomenon in both natural and synthetic systems, yet the underlying growth mechanisms remain largely unresolved. Using liquid-phase transmission electron microscopy (TEM), we elucidate the real-time growth pathways of covalent organic framework (COF) onion nanostructures, which involve graphitic layer formation, subsequent layer attachment, onion ring closure, and structural relaxation. This process is marked by variations in orientation and curvature, driven by the dynamic formation of the COF structure, which further regulates order-disorder transition and defect generation within the framework. Our in situ TEM characterizations provide valuable insights into how molecular arrangement drives the formation of complex nanostructures. We anticipate that direct imaging of COF nanostructure growth in liquids will open new opportunities for controlling COF crystal morphology, composition, and hierarchical structure development.

  View details for DOI 10.1021/jacs.4c14196

  View details for PubMedID 39575868

• Sulfur and Wavy-Stacking Boosted Superior Lithium Storage in 2D Covalent Organic Frameworks. Small (Weinheim an der Bergstrasse, Germany) Li, N., Zhu, J., Yang, C., Huang, S., Jiang, K., Zheng, Q., Yang, Y., Mao, H., Han, S., Zhu, L., Zhuang, X. 2024: e2405974

  Abstract

  2D conjugated covalent organic frameworks (c-COFs) provide an attractive foundation as organic electrodes in energy storage devices, but their storage capability is long hindered by limited ion accessibility within densely pi-pi stacked interlayers. Herein, two kinds of 2D c-COFs based on dioxin and dithiine linkages are reported, which exhibit distinct in-plane configurations-fully planar and undulated layers. X-ray diffraction analysis reveals wavy square-planar networks in dithiine-bridged COF (COF-S), attributed to curved C─S─C bonds in the dithiine linkage, whereas dioxin-bridged COF (COF-O) features densely packed fully planar layers. Theoretical and experimental results elucidate that the undulated stacking within COF-S possesses an expanded layer distance of 3.8 A and facilitates effective and rapid Li+ storage, yielding a superior specific capacity of 1305 mAh g-1 at 0.5 A g-1, surpassing that of COF-O (1180 mAh g-1 at 0.5 A g-1). COF-S also demonstrates an admirable cycle life with 80.4% capacity retention after 5000 cycles. As determined, self-expanded wavy-stacking geometry, S-enriched dithiine in COF-S enhances the accessibility and redox activity of Li storage, allowing each phthalocyanine core to store 12 Li+ compared to 8 Li+ in COF-O. These findings underscore the elements and stacking modes of 2D c-COFs, enabling tunable layer distance and modulation of accessible ions.

  View details for DOI 10.1002/smll.202405974

  View details for PubMedID 39148200

• Multivariate Machine Learning Models of Nanoscale Porosity from Ultrafast NMR Relaxometry. Angewandte Chemie (International ed. in English) Fricke, S. N., Salgado, M., Menezes, T., Costa Santos, K. M., Gallagher, N., Song, A. Y., Wang, J., Engler, K., Wang, Y., Mao, H., Reimer, J. A. 2024: e202316664

  Abstract

  Nanoporous materials are of great interest in many applications, such as catalysis, separation, and energy storage. The performance of these materials is closely related to their pore sizes, which are inefficient to determine through the conventional measurement of gas adsorption isotherms. Nuclear magnetic resonance (NMR) relaxometry has emerged as a technique highly sensitive to porosity in such materials. Nonetheless, streamlined methods to estimate pore size from NMR relaxometry remain elusive. Previous attempts have been hindered by inverting a time domain signal to relaxation rate distribution, and dealing with resulting parameters that vary in number, location, and magnitude. Here we invoke well-established machine learning techniques to directly correlate time domain signals to BET surface areas for a set of metal-organic frameworks (MOFs) imbibed with solvent at varied concentrations. We employ this series of MOFs to establish a correlation between NMR signal and surface area via partial least squares (PLS), following screening with principal component analysis, and apply the PLS model to predict surface area of various nanoporous materials. This approach offers a high-throughput, non-destructive way to assess porosity in c.a. one minute. We anticipate this work will contribute to the development of new materials with optimized pore sizes for various applications.

  View details for DOI 10.1002/anie.202316664

  View details for PubMedID 38290006

• Unveiling the complexity of nanodiamond structures. Proceedings of the National Academy of Sciences of the United States of America Zheng, Q., Shi, X., Jiang, J., Mao, H., Montes, N., Kateris, N., Reimer, J. A., Wang, H., Zheng, H. 2023; 120 (23): e2301981120

  Abstract

  Understanding nanodiamond structures is of great scientific and practical interest. It has been a long-standing challenge to unravel the complexity underlying nanodiamond structures and to resolve the controversies surrounding their polymorphic forms. Here, we use transmission electron microscopy with high-resolution imaging, electron diffraction, multislice simulations, and other supplementary techniques to study the impacts of small sizes and defects on cubic diamond nanostructures. The experimental results show that common cubic diamond nanoparticles display the (200) forbidden reflections in their electron diffraction patterns, which makes them indistinguishable from new diamond (n-diamond). The multislice simulations demonstrate that cubic nanodiamonds smaller than 5 nm can present the d-spacing at 1.78 Å corresponding to the (200) forbidden reflections, and the relative intensity of these reflections increases as the particle size decreases. Our simulation results also reveal that defects, such as surface distortions, internal dislocations, and grain boundaries can also make the (200) forbidden reflections visible. These findings provide valuable insights into the diamond structural complexity at nanoscale, the impact of defects on nanodiamond structures, and the discovery of novel diamond structures.

  View details for DOI 10.1073/pnas.2301981120

  View details for PubMedID 37253001

• A scalable solid-state nanoporous network with atomic-level interaction design for carbon dioxide capture. Science advances Mao, H., Tang, J., Day, G. S., Peng, Y., Wang, H., Xiao, X., Yang, Y., Jiang, Y., Chen, S., Halat, D. M., Lund, A., Lv, X., Zhang, W., Yang, C., Lin, Z., Zhou, H. C., Pines, A., Cui, Y., Reimer, J. A. 2022; 8 (31): eabo6849

  Abstract

  Carbon capture and sequestration reduces carbon dioxide emissions and is critical in accomplishing carbon neutrality targets. Here, we demonstrate new sustainable, solid-state, polyamine-appended, cyanuric acid-stabilized melamine nanoporous networks (MNNs) via dynamic combinatorial chemistry (DCC) at the kilogram scale toward effective and high-capacity carbon dioxide capture. Polyamine-appended MNNs reaction mechanisms with carbon dioxide were elucidated with double-level DCC where two-dimensional heteronuclear chemical shift correlation nuclear magnetic resonance spectroscopy was performed to demonstrate the interatomic interactions. We distinguished ammonium carbamate pairs and a mix of ammonium carbamate and carbamic acid during carbon dioxide chemisorption. The coordination of polyamine and cyanuric acid modification endows MNNs with high adsorption capacity (1.82 millimoles per gram at 1 bar), fast adsorption time (less than 1 minute), low price, and extraordinary stability to cycling by flue gas. This work creates a general industrialization method toward carbon dioxide capture via DCC atomic-level design strategies.

  View details for DOI 10.1126/sciadv.abo6849

  View details for PubMedID 35921416

• Origin of enhanced water oxidation activity in an iridium single atom anchored on NiFe oxyhydroxide catalyst. Proceedings of the National Academy of Sciences of the United States of America Zheng, X., Tang, J., Gallo, A., Garrido Torres, J. A., Yu, X., Athanitis, C. J., Been, E. M., Ercius, P., Mao, H., Fakra, S. C., Song, C., Davis, R. C., Reimer, J. A., Vinson, J., Bajdich, M., Cui, Y. 2021; 118 (36)

  Abstract

  The efficiency of the synthesis of renewable fuels and feedstocks from electrical sources is limited, at present, by the sluggish water oxidation reaction. Single-atom catalysts (SACs) with a controllable coordination environment and exceptional atom utilization efficiency open new paradigms toward designing high-performance water oxidation catalysts. Here, using operando X-ray absorption spectroscopy measurements with calculations of spectra and electrochemical activity, we demonstrate that the origin of water oxidation activity of IrNiFe SACs is the presence of highly oxidized Ir single atom (Ir5.3+) in the NiFe oxyhydroxide under operating conditions. We show that the optimal water oxidation catalyst could be achieved by systematically increasing the oxidation state and modulating the coordination environment of the Ir active sites anchored atop the NiFe oxyhydroxide layers. Based on the proposed mechanism, we have successfully anchored Ir single-atom sites on NiFe oxyhydroxides (Ir0.1/Ni9Fe SAC) via a unique in situ cryogenic-photochemical reduction method that delivers an overpotential of 183 mV at 10 mA cm- 2 and retains its performance following 100 h of operation in 1 M KOH electrolyte, outperforming the reported catalysts and the commercial IrO2 catalysts. These findings open the avenue toward an atomic-level understanding of the oxygen evolution of catalytic centers under in operando conditions.

  View details for DOI 10.1073/pnas.2101817118

  View details for PubMedID 34465618

• Origin of enhanced water oxidation activity in an iridium single atom anchored on NiFe oxyhydroxide catalyst PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Zheng, X., Tang, J., Gallo, A., Torres, J., Yu, X., Athanitis, C. J., Been, E., Ercius, P., Mao, H., Fakra, S. C., Song, C., Davis, R. C., Reimer, J. A., Vinson, J., Bajdich, M., Cui, Y. 2021; 118 (36)

  View details for DOI 10.1073/pnas.2101817118|1of7

  View details for Web of Science ID 000705126700008

• Revealing Molecular Mechanisms in Hierarchical Nanoporous Carbon via Nuclear Magnetic Resonance MATTER Mao, H., Tang, J., Xu, J., Peng, Y., Chen, J., Wu, B., Jiang, Y., Hou, K., Chen, S., Wang, J., Lee, H., Halat, D. M., Zhang, B., Chen, W., Plantz, A. Z., Lu, Z., Cui, Y., Reimer, J. A. 2020; 3 (6): 2093–2107

  View details for DOI 10.1016/j.matt.2020.09.024

  View details for Web of Science ID 000598228500008

• Dynamic Covalent Synthesis of Crystalline Porous Graphitic Frameworks CHEM Li, X., Wang, H., Chen, H., Zheng, Q., Zhang, Q., Mao, H., Liu, Y., Cai, S., Sun, B., Dun, C., Gordon, M. P., Zheng, H., Reimer, J. A., Urban, J. J., Ciston, J., Tan, T., Chan, E. M., Zhang, J., Liu, Y. 2020; 6 (4): 933–44

  View details for DOI 10.1016/j.chempr.2020.01.011

  View details for Web of Science ID 000526099500020

• Designing hierarchical nanoporous membranes for highly efficient gas adsorption and storage. Science advances Mao, H. n., Tang, J. n., Chen, J. n., Wan, J. n., Hou, K. n., Peng, Y. n., Halat, D. M., Xiao, L. n., Zhang, R. n., Lv, X. n., Yang, A. n., Cui, Y. n., Reimer, J. A. 2020; 6 (41)

  Abstract

  Nanoporous membranes with two-dimensional materials such as graphene oxide have attracted attention in volatile organic compounds (VOCs) and H2 adsorption because of their unique molecular sieving properties and operational simplicity. However, agglomeration of graphene sheets and low efficiency remain challenging. Therefore, we designed hierarchical nanoporous membranes (HNMs), a class of nanocomposites combined with a carbon sphere and graphene oxide. Hierarchical carbon spheres, prepared following Murray's law using chemical activation incorporating microwave heating, act as spacers and adsorbents. Hierarchical carbon spheres preclude the agglomeration of graphene oxide, while graphene oxide sheets physically disperse, ensuring structural stability. The obtained HNMs contain micropores that are dominated by a combination of ultramicropores and mesopores, resulting in high VOCs/H2 adsorption capacity, up to 235 and 352 mg/g at 200 ppmv and 3.3 weight % (77 K and 1.2 bar), respectively. Our work substantially expands the potential for HNMs applications in the environmental and energy fields.

  View details for DOI 10.1126/sciadv.abb0694

  View details for PubMedID 33028517