The RAPTR furnace: a rapid heating and cooling sample furnace for <i>in situ</i> X-ray scattering studies of temperature-induced reactions

<p>In situX-ray scattering provides valuable insights into the mechanisms and kinetics of reactions and structural transformations. For reactions and structural transformations primarily driven by temperature, and not coupled to chemical/electrochemical triggers, our ability to initiate and quench processes thermally is a practical limit for probing fast reactive phenomena. Meaningful quantitative analysis requires the dynamic phenomena to be triggered on fast time scales relative to the reaction/transformation kinetics. This article describes a new sample furnace, the Rapid-Actuating Pneumatic Thermal Reactor or RAPTR, for time-resolvedin situX-ray scattering studies initiated by temperature. The RAPTR quickly heats and cools samples by translating them into and out of a pre-heated hot zone. Using diffraction thermometry, it is shown that the samples can be heated/cooled in 10 s or less, with temperatures up to ∼1000°C being accessible. The application of the RAPTR furnace is demonstrated by exploring a fast solid-state reaction: the synthesis of scheelite-type lead tungstate, PbWO₄, from PbO and WO₃for which Pb₃WO₆is identified as a previously unrecognized reaction intermediate.</p>. Authors: Hu, Danrui; Beauvais, Michelle (ORCID:0000000203490848); Mullens, Bryce; Sanchez Monserrate, Bryan (ORCID:0000000191919968); Vornholt, Simon (ORCID:0000000194903785). DOE Contract: SC0019212; AC02-06CH11357. Subjects: Chemistry; Crystallography