High pressure, high temperature scanning tunneling microscopy

Abstract

Articles you may be interested inA new scanning tunneling microscope reactor used for high-pressure and high-temperature catalysis studies Rev. Sci. Instrum. 79, 084101 (2008); A high pressure, high temperature, scanning tunneling microscope for in situ studies of catalysts Rev.The design and performance of a high pressure, high temperature scanning tunneling microscope ͑HPHT-STM͒ system is described. The system combines an ultrahigh vacuum surface analysis/ preparation chamber with a variable pressure (5ϫ10 Ϫ10 Torr-1 atm͒ and temperature ͑300-675 K͒ STM. The STM chamber can be isolated by three gate valves and filled with 1 atm of any gas mixture. The composition of the gas can be monitored by gas chromatography. A load-lock mechanism allows the transfer of samples and tips into the chamber without exposing it to air. Heating at high pressure is achieved using a halogen lamp beneath the sample. By switching between tungsten and gold tips, the microscope can be used in both oxidizing and reducing environments at room temperature, and reducing environments at elevated temperatures. This instrument allows the exploration of surfaces in a pressure regime that few other surface sensitive techniques can work in.

Epitaxial growth of ultrathin ZrO2(111) films on Pt(111)

“…This result is in close agreement with the value of 0.36 nm reported by Meinel et al [9][10][11]. Our calculated value is equivalent to the (111) planes of face centered cubic ZrO 2 with a CaF 2 -like structure [9,15]. Because of the approximately 28% lattice misfit between ZrO 2 (111) and Pt(111), the (5×5) superstructure of Pt(111) observed at low coverage corresponds to the (4×4) superstructure of ZrO 2 (111), as described previously [11].…”

Catalysis Research of Relevance to Carbon Management: Progress, Challenges, and Opportunities

“…[195][196][197][198][199][200][201][202][203][204][205][206] Table 4 lists the principal characterization techniques that can be used at high pressures and temperatures at the solid-gas interface and also at solid-liquid interfaces with references to key review papers. Among these, sum frequency generation (SFG)-surface vibrational spectroscopy 199 (e.g., Figure 12) and the scanning probe microscopies (scanning tunneling microscopy [STM] (e.g., Figure 13) and atomic force microscopy [AFM]) 202 have the sensitivities to be applicable for studies on small area (∼1 cm 2 ) catalysts. Adsorption-reflection infrared spectroscopy 197 and synchrotron-based techniques (grazing angle X-ray diffraction and X-ray absorption) 204 can also be used for external surfaces with small areas.…”

Structure and Dynamics of Dense Monolayers of NO Adsorbed on Rh(111) in Equilibrium with the Gas Phase in the Torr Pressure Range

“…After transferring the sample to the reactor chamber, valves are closed and gases are introduced to a high pressure. The capabilities of the instrument are described elsewhere [2,3].…”