Imaging and videography
Images and videos were taken with a digital SLR camera (Canon,
EOS 100D) equipped with a high-performance standard zoom lens
(EF-S18-55mm f/3.5-5.6 IS STM).
Data availability
The raw data on particle size distribution (Fig. 1f), rheological measure-
ments (Fig. 1g, h), nitrogen sorption (Fig. 2m, n), thermogravimetric
analysis (Fig. 2o), pumping flow rate and toluene degradation (Fig. 4f,
g), and thermal conductivity measurements and reconstructed X-ray
tomography used for the image analysis (Fig. 2j–l), are available at
https://doi.org/10.5281/zenodo.3794969. All other data (raw data used
for Extended Data Figs. 1–9 and Extended Data Table 1) are available
from the corresponding authors on request.
Code availability
The codes for 3D printing and tomographic analysis are available at
https://doi.org/10.5281/zenodo.3794969.
- Pajonk, G. M. et al. Physical properties of silica gels and aerogels prepared with new
polymeric precursors. J. Non-Cryst. Solids 186 , 1–8 (1995). - Stahl, T., Brunner, S., Zimmermann, M. & Ghazi Wakili, K. Thermo-hygric properties of a
newly developed aerogel based insulation rendering for both exterior and interior
applications. Energy Build. 44 , 114–117 (2012). - Brunauer, S., Emmett, P. H. & Teller, E. Adsorption of gases in multimolecular layers. J. Am.
Chem. Soc. 60 , 309–319 (1938). - Marone, F. & Stampanoni, M. Regridding reconstruction algorithm for real-time
tomographic imaging. J. Synchrotron Radiat. 19 , 1029–1037 (2012). - Fox, P., Hall, A. & Schryer, N. L. The PORT mathematical subroutine library. ACM Trans.
Math. Softw. 4 , 104–126 (1978).
39. R: a language and environment for statistical computing (R Core Team, 2013).
40. Maxwell, J. C. VII. On stresses in rarified gases arising from inequalities of temperature.
Philos. Trans. R. Soc. Lond. 170 , 231–256 (1879).
41. Loeb, L. B. The Kinetic Theory of Gases 3rd edn, Ch. VII, 290–300 (Dover, 2004).
42. Sone, Y. Molecular Gas Dynamics Theory, Techniques, and Applications Ch. 1 (Birkhäuser,
2007).
43. Malfait, W. J., Verel, R. & Koebel, M. M. Hydrophobization of silica aerogels: insights from
quantitative solid-state NMR spectroscopy. J. Phys. Chem. C 118 , 25545–25554 (2014).
44. Malfait, W. J. et al. Surface chemistry of hydrophobic silica aerogels. Chem. Mater. 27 ,
6737–6745 (2015).
Acknowledgements We thank M. Giannakou and D. Sivaraman for help in the laboratory, D.
Rentsch for support with the NMR spectrometer, funded in part by grant 150638 from the
Swiss National Science Foundation, F. Winnefeld for support with the rheometer, A. Braun for
support with the photocatalytic setup, S. Carl for support with the infrared thermal imaging
system, R. Pauer for support with the STEM and SAED pattern analysis, N. Guerrero for video
editing and B. Fischer for TGA analysis. M.G. was supported by MSCA grant 746992.Author contributions S.Z., G.S., M.M.K. and W.J.M. designed and coordinated the study. S.Z.,
G.S., D.N. and C.U. optimized the ink formulation. G.S. and S.Z. carried out the printing
experiments, supervised by G.N. J.W. supervised the MnO 2 synthesis and light-driven pump
test. S.D. and S.Z. conducted the pumping/degradation experiments. S.Z. carried out the SEM
and BET analysis. S.B. and S.Z. conducted the thermal conductivity and infrared imaging
measurements. M.G. prepared STL files and photographic artwork. W.J.M. did the NMR
analysis. A.B. collected, and S.G. and Z.P. processed, the X-ray tomography data. S.Z. and
W.J.M. wrote the manuscript with input from all coauthors. All authors reviewed and
commented on the manuscript.Competing interests A patent for the additive manufacturing of silica aerogels (EP19208179.2)
has been filed on behalf of Empa. S.Z., G.S., W.J.M., M.M.K., C.U. and D.N. are listed as inventors.Additional information
Supplementary information is available for this paper at https://doi.org/10.1038/s41586-020-
2594-0.
Correspondence and requests for materials should be addressed to S.Z. or W.J.M.
Peer review information Nature thanks L. Zhao and the other, anonymous, reviewer(s) for their
contribution to the peer review of this work.
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