About

Jeffery Hancock is an Associate Professor of Instruction in the Department of Theatre at Northwestern University. He is a dancer, choreographer, costume designer, and teacher with extensive experience in choreography and performance. Hancock has choreographed work for various companies and festivals, including the River North Chicago Dance Company, Hubbard Street II, the Edinburgh Festival, Princess Cruise Lines, the Pegasus Players, and Northwestern's Theatre and Interpretation Center. He has also choreographed and performed in numerous musical theater productions and danced with the Lyric Opera. He is a founding member and former principal dancer of the River North Chicago Dance Company and a former company member of Hubbard Street Dance Chicago. Hancock has been nominated for Ruth Page Awards for both performance and choreography and has received a grant from the Illinois Arts Council. His dance career includes being a company member and co-artistic director of Same Planet Different World Dance Theatre, as well as dancing with Dance Kaleidoscope, Jan Erkert and Dancers, and guesting with the Joe Goode Performance Group. In addition to his choreography and performance work, Hancock teaches master classes nationally and internationally and has designed and constructed costumes for various dance companies and institutions.

Research topics

• Chemistry
• Crystallography
• Metallurgy
• Physics
• Thermodynamics
• Geology
• Materials science
• Inorganic chemistry
• Physical chemistry

Selected publications

• Mechanochemical Synthesis of Sodium and Lithium Calcium Ferrite Postspinels for Lithium-Ion Battery Cathodes

  ECS Meeting Abstracts · 2025-11-24

  article

  Calcium ferrite type postspinel compounds are of interest as prospective battery cathodes for alkali and alkaline-earth rechargeable batteries. While many postspinel compounds require high-pressure synthesis, some sodium postspinels are known to form at ambient pressure via solid-state synthesis. NaMnTiO 4 , a potential cathode material, cannot be synthesized at ambient pressure via solid-state synthesis despite thermodynamic stability calculations suggesting otherwise [1]. In this work we show that mechanochemical synthesis methods can be used to access the new sodium postspinels NaMnTiO 4 , NaMn 1.25 Ti 0.75 O 4 , and NaMn 1.5 Ti 0.5 O 4 . We additionally show that the lithium analogues LiMnTiO 4 , LiMn 1.25 Ti 0.75 O 4 , and LiMn 1.5 Ti 0.5 O 4 can be synthesized through an ion-exchange process. Galvanostatic cycling of the lithium postspinels as lithium-ion battery cathodes shows reversible cycling with a sloping profile. Capacities increased with Mn concentration up to 200 mAh·g -1 for LiMn 1.5 Ti 0.5 O 4 on first discharge at C/20 and an average discharge voltage of 3 V accessing both the Mn 2+/3+ and Mn 3+/4+ redox couples. While only half the available lithium could be extracted in all cases, each compound could also accommodate more than one lithium per formula unit yielding higher capacities. Ex-situ diffraction of the compounds taken at various states of charge show a maintenance of the postspinel structure in all cases with changes in volume at a maximum of 7% relative to the pristine. This work illustrates the promise of the postspinel structure type for lithium-ion energy storage and suggests possible further expansion of the postspinel phase space through mechanochemical synthesis methods. [1] Hancock, J. C.; Ding, P. P.; Choi, Y.; Ceder, G.; Vaughey, J. T.; Griffith, K. J.; Poeppelmeier, K. R. Electrochemistry in the Large Tunnels of Lithium Postspinel Compounds. Chem. Mater. 2024 . https://doi.org/10.1021/acs.chemmater.4c00389.

  PublisherDOI

• Electrochemistry in the Large Tunnels of Lithium Postspinel Compounds

  Chemistry of Materials · 2024-04-22 · 7 citations

  articleOpen access1st author

  Lithium spinels (LiMM’O4) are an important class of mixed-cation materials that have found uses in batteries, catalysis, and optics. Postspinels are a series of related framework structures with the AMM’O4 host composition that are formed with larger A-site cations, typically under high pressure. Postspinels have one-dimensional tunnel structures with pores that are larger than those in spinel and triangular in cross-section, but they are relatively unexplored as intercalation electrodes. While lithium postspinels have been previously found to be thermodynamically stable only at high pressures, we have identified a synthetic pathway that produces the lithium-containing materials at ambient pressure using an ion-exchange process from the corresponding sodium postspinels. Here, we report the synthesis and a survey of the electrochemical properties of 10 new lithium CaFe2O4-type postspinel compounds where M = Mn3+, V3+, Cr3+, Rh3+, Fe2+, Mg2+, Co2+ and M’ = Ti4+ and/or Sn4+. Although complete delithiation is not achieved during electrochemical cycling, many of the lithium postspinels have substantial charge storage capacity in Li battery cells owing to the ability of the large framework tunnels to accommodate more than one lithium ion per formula unit. Multiple redox couples are accessed for LiMnSnO4, Li0.96Mn0.96Sn1.04–xTixO4, Li0.96V0.96Ti1.04O4, Li0.96Cr0.96Ti1.04O4, and LiFe0.5Ti1.5O4. Compositions with moderate or poor lithium cyclability are also discussed for comparison. Redox mechanisms and trends are identified by comparing this new redox-active framework to related spinels, ramsdellites, and ‘Na0.44MnO2’ structures, and from density functional theory (DFT) electronic structures. Operando diffraction shows complex structural responses to lithium insertion and extraction in this postspinel framework. A DFT framework was proposed to identify promising lithium postspinel phases that could be accessed metastably under ambient pressure conditions and to assess their stability to lithium insertion and extraction. This work suggests that CaFe2O4-type hosts are a promising new class of lithium-ion energy storage materials.

  PublisherOA PDFDOI

• CSD 2103834: Experimental Crystal Structure Determination

  The Cambridge Structural Database · 2021-09-02

  datasetOpen access1st authorCorresponding

  An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  PublisherDOI

• CSD 2103938: Experimental Crystal Structure Determination

  The Cambridge Structural Database · 2021-09-02

  datasetOpen access1st authorCorresponding

  An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  PublisherDOI

• Expanding the Ambient-Pressure Phase Space of CaFe₂O₄-Type Sodium Postspinel Host–Guest Compounds

  ACS Organic & Inorganic Au · 2021 · 13 citations

  1st authorCorresponding
  • Chemistry
  • Crystallography
  • Inorganic chemistry

  in both the tunnel and framework sites, reminiscent of Li-rich spinels. Trends in the thermodynamic stability of the new compounds are explained on the basis of crystal-chemistry and density functional theory (DFT). Further DFT calculations examine the relative stability of the CF versus spinel structures at various degrees of sodium extraction in the context of electrochemical battery reactions.

  PublisherDOI

• CSD 2103825: Experimental Crystal Structure Determination

  The Cambridge Structural Database · 2021-09-02

  datasetOpen access1st authorCorresponding

  An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  PublisherDOI

• CSD 2103925: Experimental Crystal Structure Determination

  The Cambridge Structural Database · 2021-09-02

  datasetOpen access1st authorCorresponding

  An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  PublisherDOI

• CSD 2103929: Experimental Crystal Structure Determination

  The Cambridge Structural Database · 2021-09-02

  datasetOpen access1st authorCorresponding

  An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  PublisherDOI

• CSD 2103828: Experimental Crystal Structure Determination

  The Cambridge Structural Database · 2021-09-02

  datasetOpen access1st authorCorresponding

  An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  PublisherDOI

• CSD 2103718: Experimental Crystal Structure Determination

  The Cambridge Structural Database · 2021-09-02

  datasetOpen access1st authorCorresponding

  An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  PublisherDOI

Frequent coauthors

• Kenneth R. Poeppelmeier

  Northwestern University

  42 shared

• Gerbrand Ceder

  University of California, Berkeley

  29 shared

• Kent J. Griffith

  27 shared

• John T. Vaughey

  Argonne National Laboratory

  25 shared

• Yunyeong Choi

  25 shared

• Christopher J. Bartel

  University of Minnesota

  21 shared

• Saul H. Lapidus

  Argonne National Laboratory

  20 shared

• Allison Wustrow

  Colorado State University

  7 shared

Awards & honors

• Ruth Page Award nominations for Performance and Choreography
• Grant recipient from the Illinois Arts Council