Abstract
In recent years, an increasing number of laboratories have been applying in situ
heating (and ultimately, gas reaction) techniques in electron microscopy studies of catalysts and
other nanophase materials. With the advent of aberration-corrected electron microscopes that provide
sub-A˚ ngstro¨m image resolution, it is of great interest to study the behavior of materials at elevated
temperatures while maintaining the resolution capabilities of the microscope. In collaboration
with Protochips Inc., our laboratory is developing an advanced capability for in situ heating
experiments that overcomes a number of performance problems with standard heating stage technologies.
The new heater device allows, for example, temperature cycling from room temperature
to greater than 10008C in 1 ms (a heating rate of 1 million Centigrade degrees per second) and cooling
at nearly the same rate. It also exhibits a return to stable operation (drift controlled by the
microscope stage, not the heater) in a few seconds after large temperature excursions. With Protochips
technology, we were able to demonstrate single atom imaging and the behavior of nanocrystals
at high temperatures, using high-angle annular dark-field imaging in an aberration-corrected
(S)TEM. The new capability has direct applicability for remote operation and (ultimately) for gas
reaction experiments using a specially designed environmental cell
