All Publications

  • Regioisomeric Spirobifluorene CANAL Ladder Polymers and Their Gas Separation Performance. ACS macro letters Robinson, A. M., Xia, Y. 2024: 118-123


    We synthesized and characterized two isomeric microporous hydrocarbon ladder polymers from catalytic arene norbornene annulation (CANAL) of regioisomeric bis-norbornene fused spirobifluorenes, where the ladder chains are connected either through the same fluorene unit or across two different fluorene units in spirobifluorene. This pair of isomeric polymers was used to investigate the effect of ladder macromolecular structures on the microporosity and transport properties. Both polymers form mechanically intact films with thermal stability up to 480 °C and relatively high BET surface areas. The polymer formed from 2,7-dibromospirobifluorene showed higher BET surface area and higher gas permeability than the polymer from 2,2'-dibromospirobifluorene despite similar intersegmental spacing as indicated by X-ray scattering. The aging behavior for both polymers followed the same trend as the previously reported CANAL-fluorene polymers, with dramatically increased permselectivities over time, resulting in gas separation performance above the 2008 upper bounds for H2/CH4 and O2/N2.

    View details for DOI 10.1021/acsmacrolett.3c00725

    View details for PubMedID 38193743

  • Tailoring the mechanical and combustion performance of B/HTPB composite solid fuel with covalent interfaces COMPOSITES SCIENCE AND TECHNOLOGY Jiang, Y., Leem, J., Robinson, A. M., Wu, S., Huynh, A. H., Ka, D., Zhao, R., Xia, Y., Zheng, X. 2024; 245
  • Enhanced H2O2 Upcycling into Hydroxyl Radicals with GO/Ni:FeOOH-Coated Silicon Nanowire Photocatalysts for Wastewater Treatment. Nano letters Ning, R., Kim, S., Sun, E., Jiang, Y., Baek, J., Li, Y., Robinson, A., Vallez, L., Zheng, X. 2023


    There remains continued interest in improving the advanced water oxidation process [e.g., ultraviolet (UV)/hydrogen peroxide (H2O2)] for more efficient and environmentally friendly wastewater treatment. Here, we report the design, fabrication, and performance of graphene oxide (GO, on top)/nickel-doped iron oxyhydroxide (Ni:FeOOH, shell)/silicon nanowires (SiNWs, core) as a new multifunctional photocatalyst for the degradation of common pollutants like polystyrene and methylene blue through enhancing the hydroxyl radical (•OH) production rate of the UV/H2O2 system. The photocatalyst combines the advantages of a large surface area and light absorption characteristics of SiNWs with heterogeneous photo-Fenton active Ni:FeOOH and photocatalytically active/charge separator GO. In addition, the built-in electric field of GO/Ni:FeOOH/SiNWs facilitates the charge separation of electrons to GO and holes to Ni:FeOOH, thus boosting the photocatalytic performance. Our photocatalyst increases the •OH yield by 5.7 times compared with that of a blank H2O2 solution sample and also extends the light absorption spectrum to include visible light irradiation.

    View details for DOI 10.1021/acs.nanolett.3c00696

    View details for PubMedID 37459426

  • Data-Driven Approach to Tailoring Mechanical Properties of a Soft Material ADVANCED FUNCTIONAL MATERIALS Leem, J., Jiang, Y., Robinson, A., Xia, Y., Zheng, X. 2023
  • Hydrocarbon ladder polymers with ultrahigh permselectivity for membrane gas separations. Science (New York, N.Y.) Lai, H. W., Benedetti, F. M., Ahn, J. M., Robinson, A. M., Wang, Y., Pinnau, I., Smith, Z. P., Xia, Y. 2022; 375 (6587): 1390-1392


    Membranes have the potential to substantially reduce energy consumption of industrial chemical separations, but their implementation has been limited owing to a performance upper bound-the trade-off between permeability and selectivity. Although recent developments of highly permeable polymer membranes have advanced the upper bounds for various gas pairs, these polymers typically exhibit limited selectivity. We report a class of hydrocarbon ladder polymers that can achieve both high selectivity and high permeability in membrane separations for many industrially relevant gas mixtures. Additionally, their corresponding films exhibit desirable mechanical and thermal properties. Tuning of the ladder polymer backbone configuration was found to have a profound effect on separation performance and aging behavior.

    View details for DOI 10.1126/science.abl7163

    View details for PubMedID 35324307

  • Catalytic Arene (oxa)Norbornene Annulation (CANAL) TRENDS IN CHEMISTRY Leibham, A. M., Xia, Y. 2020; 2 (7): 680–81