A Tour of Zaera Lab

This stainless-steel vessel is evacuated to a base pressure of approximately 1·E-10 Torr with a Seiko magnetically levitated 400 l/s turbomolecular pump.  It is equipped a VSW 50 mm concentric-hemisphere energy analyzer, a Laybold Al/Mg dual-anode X-ray source with homemade electronics, a home-made electron gun, a Phi 04-300 differentially-pumped ion source, and an Extrel mass quadrupole (0 - 800 amu) with a Bessel box energy analyzer and electron impact excitation.  The sample is mounted in a x-y-z-q centered manipulator capable of resistively heating to up to > 1300 K and of cooling to < 90 K by using a liquid nitrogen reservoir.  The temperature of the sample is measured by a thermocouple spot-welded to the side of the sample, and regulated by a homemade AC controller.  A gas manifold and several leak valves are used to introduce gases into the chamber in a controlled manner.

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This stainless-steel volume is pumped by a CTI-8 4000 l/s cryopump to a base pressure below 1·E-10 Torr.  It has an Ion Tech FAB/ion gun for sample cleaning, an UTI-100C mass quadrupole with a home-made retractable nozzle for selective detection of desorbing gases from the solid sample, and a Bruker Equinox 55 spectrometer setup for single grazing reflection from the sample inside the vacuum environment.  The manipulator is on-center, placed horizontally to translate the sample between the cleaning/TPD and RAIRS stages, and capable of resistive heating to > 1300 K, liquid nitrogen cooling to < 90 K.  The temperature is controlled via a spot-welded thermocouple and a homemade temperature controller.  A gas manifold and several leak valves are used to introduce gases into the chamber.  A retractable high-pressure cell for in-situ RAIRS detection of adsorbed species during catalysis is under construction.

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This is a stainless-steel volume evacuated with a Seiko 400 l/s magnetically levitated turbomolecular pump to a base pressure of about 1·E-10 Torr.  It contains a VG 100 mm concentric hemispheres energy analyzer, a VG Al/Mg dual-anode X-ray source, a home-made electron gun, a Kratos differentially-pumped ion source, and an UTI-100C mass quadrupole with retractable nozzle for selective detection of desorbing gases from the solid sample.  The sample is mounted in a long travel on-center z-q manipulator capable of resistively heating to up to > 1300 K and of cooling to < 60 K by using a pumped liquid nitrogen reservoir.  The temperature of the sample is measured by a thermocouple spot-welded to the side of the sample, and regulated by a homemade AC controller.  A gas manifold and several leak valves are used to introduce gases into the chamber in a controlled manner.

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This is a 6-liter stainless steel chamber evacuated with a Seiko magnetically-levitated 400 l/s turbomolecular pump to a base pressure around 2·E-10 Torr.  The chamber is equipped with a Specs IQE 10/35 sputtering gun, an UTI 100C mass quadrupole placed out of line-of-sight, and an effusive molecular beam which consists of a 1.2 cm diameter multichannel array.  The gas flux is fixed by setting both the leak valve and the backing gas pressure, which is measured by a MKS Baratron (PDR-C-1C) pressure gauge.  A movable stainless steel flag is placed between the doser and the sample to intercept the beam at will.  The sample is mounted in a x-y-z-q centered manipulator capable of resistively heating to up to > 1300 K and of cooling to < 90 K by using a liquid nitrogen reservoir.  The temperature of the sample is measured by a thermocouple spot-welded to the side of the sample, and regulated by a homemade AC controller.

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This is a homemade-modified Laybold-Heraeus commercial stainless-steel apparatus with two volumes, each pumped with a turbomolecular pump.  The main vessel has an Al anode x-ray source, a 100 mm concentric hemisphere energy analyzer with multichannel array detection, a Phi 04-191 rasterable sputtering gun, and an UTI 100C mass quadrupole.  The adjacent volume has a sputtering gun, and can be used for high-pressure treatments and as a micro-batch reactor.  The manipulator is set horizontally, in a bar designed for fast transfer between the two vacuum positions and the outside atmosphere, and can be used for sample heating and cooling between approximately 150 and 900 K.

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This stainless-steel chamber, currently in the final stages of construction, is evacuated with a Edwards 1000 l/s turbomolecular pump.  It is presently equipped with a homemade four-grid retarding field analyzer and a Varian off-center electron gun for LEED and AES, a Specs IQE 10/35 sputtering gun, and an x-y-z-q centered manipulator capable of resistively heating to up to > 1300 K and of cooling to < 90 K by using a liquid nitrogen reservoir.  A homemade precision temperature controller is used for temperature ramping.  A centered double-tube system has been designed to act as a nanoliter-sized reactor, by allowing for high-flux injection of gas mixtures to a surface placed directly in front of the central nozzle, and collection and detection of the desorbing gases via the outer differentially pumped cylinder and a UTI 100C mass quadrupole.

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A Mattson Sirius 100 Fourier-transform infrared spectrometer has been adapted for the characterization of solid-liquid interfaces.  The infrared beam exiting the interferometer is directed through a variable-angle polarizer towards a cell especially designed for the characterization of molecules adsorbed on surfaces from a liquid phase in a single reflection-absorption (RAIRS) mode.  The light is focussed through a calcium fluoride window onto the flat substrate, which is immersed in the reacting solution, and the reflected beam is picked up after exiting the other side of the same prism by a set of mirrors and focused onto a MCT detector.  The cell is equipped with a counter electrode in order to allow for surface cleaning by an electrochemical treatment.   The liquid in the cell can be flowed through a volume above the surface, a film of a thickness that can be set by a micrometer.  Gases can be bubbled in for purging as well, and electrochemical studies can be carried out by using a third reference electrode.

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A second Mattson Cignus 100 Fourier-transform infrared spectrometer has been adapted for the characterization of surfaces under non-vacuum conditions.  A reflection-absorption infrared spectroscopy (RAIRS) arrangement has been setup to characterize self-assembled monolayers.  The optics are interchangeable with a second set for the characterization of solid-liquid interfaces analogous to that used in the instrument described above.

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An infrared cell is used for transmission infrared characterization of powder samples, which are pressed into pellets and held in the path of the infrared beam of a Brucker Tensor 27 FT-IR interferometer in between two sealing NaCl windows. The temperature of the cell is monitored by a thermocouple placed in a thin tube close to the sample, and can be varied between –140 and 600 °C by using a combination of liquid nitrogen cooling and electric heating. The cell is connected to a gas-handling system for pumping down to a few mTorr or filling the cell with atmospheric pressures of the desired gases.  The gas handling system can also be connected to a microbatch reactor ("Hector"), which consists of a stainless-steel loop of 0.20 liters total volume connected to a metal bellows pump (Metal Bellows Corp., MB-21) for continuous gas circulation, a MKS Baratron vacuum gauge (PDR-C-1B) for gas pressure measurements, and a gas inlet manifold.  This loop is linked through a 1.0 m-long capillary tube to a computer interfaced Dycor MA-200M quadrupole mass spectrometer for gas analysis, and to a disconnectable glass U-tube for the study of supported catalysts and for gas trapping when further sample analysis is required.

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A second Mattson Cignus 100 FTIR is available for both vacuum and non-vacuum experiments.  This instrument is presently not in use, but is to be setup as a RAIRS instrument for sigle crystal samples under UHV.

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