Strong shock wave interactions with ceramic material ceria (CeO 2 ) in presence of O 2 and N 2 gases were investigated using free piston driven shock tube (FPST). FPST is used to heat the test gas to very high temperature of about 6800-7700 K (estimated) at pressure of about 6.8-7.2 MPa for short duration (2-4 ms) behind the reflected shock wave. Ceria is subjected to super heating and cooling at the rate of about 10 6 K/s. Characterization of CeO 2 sample was done before and after exposure to shock heated test gases (O 2 and N 2 ). The surface composition, crystal structure, electronic structure and surface morphology of CeO 2 ceramic were examined using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). Results obtained from the experimental investigations show that CeO 2 can withstand high pressure accompanied by thermal shock without changing its crystal structure. Reducible CeO 2 releases lattice oxygen making it possible to shift between reduced and oxidized states upon the interaction with shock heated gas. Due to such reaction mechanism, CeO 2 ceramic undergoes nitrogen doping with decrease in lattice parameter. Investigations reveal that CeO 2 retains its crystal structure during strong shock interaction, even at elevated pressure.

The building blocks of life, amino acids, are believed to have been synthesized in the extreme conditions that prevail in space, starting from simple molecules containing hydrogen, carbon, oxygen and nitrogen. However, the fate and role of amino acids when they are subjected to similar processes largely remain unexplored. Here we report, for the first time, that shock processed amino acids tend to form complex agglomerate structures. Such structures are formed on timescales of about 2 ms due to impact induced shock heating and subsequent cooling. This discovery suggests that the building blocks of life could have self-assembled not just on Earth but on other planetary bodies as a result of impact events. Our study also provides further experimental evidence for the ‘threads’ observed in meteorites being due to assemblages of (bio)molecules arising from impact-induced shocks.

The reducibility of synthesized ceria‐stabilized zirconia (CSZ) with strong shock‐heated test gases is investigated. Free piston‐driven shock tube operating at hypersonic speed at Mach number of 6–8 has been used to heat the ultrahigh pure test gases like Ar to ~12800 K, N2 to ~7960 K, and O2 to ~5500 K at a medium reflected shock pressure (5.0–7.4 MPa) for a short duration of 1–2 ms test time. Under this extreme thermodynamic condition, test gases undergo real gas effects. The structural and spectroscopic investigations of CSZ (Ce2Zr2O8) after interaction with shock‐heated argon gas show pyrochlore structure of Ce2Zr2O7−δ which is observed to be black in color. In presence of shock‐heated N2 gas, CSZ remains in fluorite structure by changing its color to pale green as nitrogen atoms fill oxygen vacancies. After O2 interaction with the shock wave, CSZ remains pale yellow but the X‐ray diffraction pattern shows the presence of monoclinic ZrO2 due to phase separation. During reduction process, Ce4+ has been reduced to Ce3+ which is an unusual effect. In this study, the catalytic and surface recombination effects of CSZ due to shock‐induced compression in millisecond timescale are presented.

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A new two‐step procedure for the synthesis of MoS2 nanotubes using lead as a growth promoter is reported. In the first step, molybdenum suboxide nanowhiskers containing a small amount of lead atoms were created by exposing a pressed MoS2+Pb mixture to highly compressed shock‐heated argon gas, with estimated temperatures exceeding 9900 K. In the second step, these molybdenum suboxide nanowhiskers served as templates for the sulfidization of the oxide into MoS2 nanotubes (by using H2S gas in a reducing atmosphere at 820 °C). Unlike the case of WS2 nanotubes, the synthesis of a pure phase of MoS2 nanotubes from molybdenum oxide has proven challenging, due mostly to the volatile nature of the latter at the high requisite reaction temperatures (>800 °C). In contrast, the nature and apparent reaction mechanism of the method reported herein are amenable to future scale‐up. The high‐temperature shockwave system should also facilitate the synthesis of new nanostructures from other layered materials.