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 Astrobiology and Ocean Worlds (3225): People
Joseph  Razzell Hollis's Picture
Jet Propulsion Laboratory
M/S 183-301
4800 Oak Grove Drive
Pasadena, CA 91109
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Curriculum Vitae:

Joseph Razzell Hollis

Joseph (also known as Joby) is a NASA postdoctoral fellow and visiting researcher at JPL, sponsored by the Universities Space Research Association (USRA). Joby is from the UK, where he did his Ph.D. on spectroscopic analysis of semiconducting polymers used to make flexible, printable solar cells.

At JPL, Joby is working on the SHERLOC instrument, a deep UV Raman and fluorescence spectrometer that is part of the Mars 2020 rover’s scientific payload. SHERLOC is designed to detect complex organic molecules that may be a sign of past life on Mars, even at low concentrations. Joby is using his experience of studying the properties of organic films within plastic electronic devices to develop analytical methods to improve our understanding of data collected by SHERLOC, in order to accurately identify biologically relevant organic compounds even at low concentrations, and map their distribution within samples investigated on the Martian surface.

  • Ph.D. Physics, Imperial College London, UK, 2016.
  • M.Res. Plastic Electronics, Imperial College London, UK, 2012.
  • M.Chem. Chemistry, Sussex University, UK, 2011.

Research Interests

Ultraviolet/visible wavelength Raman and fluorescence spectroscopy of complex organic molecules for detection of past life on Mars and other planetary surfaces.


Mars 2020 Icon Mars 2020
NASA's Mars 2020 mission will build upon many discoveries from the Curiosity Mars rover and the two Mars Exploration Rovers, Spirit and Opportunity by taking the next key steps in our understanding of Mars' potential as a habitat for past or present life.

Professional Experience

NASA Postdoctoral Program (NPP) Fellow, Jet Propulsion Laboratory, Pasadena, CA, 2018 – Present

Community Service
  • Trustee of Pride in STEM, a UK-based charity with the goal of promoting visibility of LGBT+ people in science, technology, engineering and mathematics, while encouraging greater inclusivity of both minority gender and sexual identities by scientific organizations.
  • Co-organizer of Out Thinkers, a regular event that aims to celebrate and promote LGBT+ scientists by giving them the opportunity to talk about their work.
  • Runs the LGBT+ Physics twitter group.

Selected Publications
  1. Sapers, H. M., Razzell-Hollis, J., Bhartia, R., Beegle, L. W., Orphan, V. J., Amend, J. P., et al. (2019). The Cell and the Sum of Its Parts: Patterns of Complexity in Biosignatures as Revealed by Deep UV Raman Spectroscopy. Front. Microbiol. 10, 1–15. doi:10.3389/fmicb.2019.00679.
  2. Wood, S.; Hollis, J. R.; Kim, J.-S. Raman Spectroscopy as an Advanced Structural Nanoprobe for Conjugated Molecular Semiconductors. J. Phys. D. Appl. Phys. 201750 (7), 73001.
  3. Razzell-Hollis, J.; Fleischli, F.; Jahnke, A. A.; Stingelin, N.; Seferos, D. S.; Kim, J.-S. Effects of Side-Chain Length and Shape on Polytellurophene Molecular Order and Blend Morphology. J. Phys. Chem. C 2017121 (4), 2088–2098.
  4. Razzell-Hollis, J.; Thiburce, Q.; Tsoi, W. C.; Kim, J.-S. Interfacial Chemical Composition and Molecular Order in Organic Photovoltaic Blend Thin Films Probed by Surface-Enhanced Raman Spectroscopy. ACS Appl. Mater. Interfaces 20168, 31469–31481.
  5. Razzell-Hollis, J.; Limbu, S.; Kim, J.-S. Spectroscopic Investigations of Three-Phase Morphology Evolution in Polymer: Fullerene Solar Cell Blends. J. Phys. Chem. C 2016120 (20), 10806–10814.
  6. Hellmann, C.; Treat, N. D.; Scaccabarozzi, A. D.; Razzell Hollis, J.; Fleischli, F. D.; Bannock, J. H.; de Mello, J.; Michels, J. J.; Kim, J.-S.; Stingelin, N. Solution Processing of Polymer Semiconductor: Insulator Blends-Tailored Optical Properties through Liquid-Liquid Phase Separation Control. J. Polym. Sci. Part B Polym. Phys. 201553, 304–310.
  7. Razzell-Hollis, J.; Wade, J.; Tsoi, W. C.; Soon, Y.; Durrant, J.; Kim, J.-S. Photochemical Stability of High Efficiency PTB7:PC70BM Solar Cell Blends. J. Mater. Chem. A 20142, 20189–20195.
  8. Razzell-Hollis, J.; Tsoi, W. C.; Kim, J.-S. Directly Probing the Molecular Order of Conjugated Polymer in OPV Blends Induced by Different Film Thicknesses, Substrates and Additives. J. Mater. Chem. C 20131, 6235–6243.
  9. Tsoi, W. C.; Zhang, W.; Razzell Hollis, J.; Suh, M.; Heeney, M.; McCulloch, I.; Kim, J.-S. In-Situ Monitoring of Molecular Vibrations of Two Organic Semiconductors in Photovoltaic Blends and Their Impact on Thin Film Morphology. Appl. Phys. Lett. 2013102 (17), 173302.

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