title: Method for local temperature measurement in a nanoreactor for in situ high-resolution electron microscopy.
abstract: In situ high-resolution transmission electron microscopy (TEM) of solids under reactive gas conditions can be facilitated by microelectromechanical system devices called nanoreactors. These nanoreactors are windowed cells containing nanoliter volumes of gas at ambient pressures and elevated temperatures. However, due to the high spatial confinement of the reaction environment, traditional methods for measuring process parameters, such as the local temperature, are difficult to apply. To address this issue, we devise an electron energy loss spectroscopy (EELS) method that probes the local temperature of the reaction volume under inspection by the electron beam. The local gas density, as measured using quantitative EELS, is combined with the inherent relation between gas density and temperature, as described by the ideal gas law, to obtain the local temperature. Using this method we determined the temperature gradient in a nanoreactor in situ, while the average, global temperature was monitored by a traditional measurement of the electrical resistivity of the heater. The local gas temperatures had a maximum of 56 °C deviation from the global heater values under the applied conditions. The local temperatures, obtained with the proposed method, are in good agreement with predictions from an analytical model.
authors.affiliation: ChemE, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands.
authors.forename: S B
authors.initials: SB
authors.lastname: Vendelbo
authors.forename: P J
authors.initials: PJ
authors.lastname: Kooyman
authors.forename: J F
authors.initials: JF
authors.lastname: Creemer
authors.forename: B
authors.initials: B
authors.lastname: Morana
authors.forename: L
authors.initials: L
authors.lastname: Mele
authors.forename: P
authors.initials: P
authors.lastname: Dona
authors.forename: B J
authors.initials: BJ
authors.lastname: Nelissen
authors.forename: S
authors.initials: S
authors.lastname: Helveg
mesh_terms: D004583:Electrons; D005740:Gases / Q000737:chemistry; D008854:Microscopy, Electron / Q000379:methods*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D046590:Spectroscopy, Electron Energy-Loss / Q000379:methods; D013696:Temperature
chemical_list: D005740:Gases
keywords: Ambient conditions; Electron energy loss spectroscopy; Heat transfer; In-situ TEM; Nanoreactor; Temperature