Temperature is one of the most important factors affecting the state and behavior of materials. In situ heating transmission electron microscopy (TEM) is a powerful tool for understanding such temperature effects, and recently in situ heating TEM has made significant progress in terms of temperature available and resolution attained. This article briefly describes newly developed specimen-heating holders, which are useful in carrying out in situ heating TEM experiments. It then focuses on three main applications of these specimen holders: solid–solid reactions, solid–liquid reactions (including highresolution observation of a solid–liquid interface, size dependence of the melting temperatures of one-, two- and three-dimensionally reduced systems, size dependence of the contact angle of fine metal liquid, and wetting of Si with liquid Au or Al) and solid–gas reactions. These results illustrate the benefit of in situ heating TEM for providing fundamental information on temperature effects on materials.

Electromagnetic fields presents in some real materials have been observed using electron holography and a simple method named the Shadow Image Distortion (SID) method which we have developed. The in-situ electron holography observation of the electric field surrounding a ceramic particle showed the rapid degradation of dielectric properties of the particle at an elevated temperature. The cross sectional view of mean electrostatic potential distributions in a silicon device has been observed. In-situ electron holography and SID observations showed the electrostatic potential distribution across a reverse biased p-n junction in a compound semiconductor. The SID method using a dedicated tool allowed single-step imaging of 2D maps of electromagnetic field.

The processes of phase transformation in individual nanoparticles of FePt and FePtCu synthesized by the reverse micelle method, which are chemically homogeneous and monodisperse, have been investigated by an in-situ HREM observation in a FE-TEM. Polycrystalline FePt particles, initially of chemically disordered face-centered cubic phase (A1) were reconstructed into A1 single crystals between 25 °C and 650 °C, followed by phase transformation from A1 to chemically ordered face-centered tetragonal phase (L10) which began between 650 °C and 680 °C. The coalescence began concurrently with phase transformation, i. e., between 650 °C and 680 °C. They turned to be a round-shaped L10 particle between 680 °C and 720 °C. The single crystal formation, the phase transformation from A1 to L10, the coalescence and the round-shaped particle formation were also observed in the FePtCu nanoparticles. The temperatures of single crystal formation, phase transformation (and coalescence) and round-shaped particle formation of the FePtCu nanoparticles were between 25 °C and 500 °C, between 550 °C and 600 °C and between 600 °C and 650 °C, respectively. These temperatures were substantially lower than those for the FePt nanoparticles.

In situ transmission electron microscopy (TEM) studies allow one to determine the structure, chemistry, and kinetic behavior of solid–liquid (S–L) interfaces with subnanometer spatial resolution. This article illustrates some important contributions of in situ TEM to our understanding of S–L interfaces in Al-Si alloys and liquid In particles in Al and Fe matrices.Four main areas are discussed:ordering in the liquid at a S–L interface, compositional changes across the interface, the kinetics and mechanisms of interface migration, and the contact angles and equilibrium melting temperature of small particles.Results from these studies reveal that (1)partially ordered layers form in the liquid at a Si{111} S–L interface in an Al–Si alloy, (2)the crystalline and compositional changes occur simultaneously across an Al S–L interface, (3)the Al interface is diffuse and its growth can be followed at velocities of a fewnm/s at extremely low undercoolings, and (4)the melting temperature of In particles less than ~ 10 nm in diameter can be raised or lowered in Al or Fe, depending on the contact angle that the S–L interface makes at the three-phase junction. These results illustrate the benefits of in situ TEM for providing fundamental insight into the mechanisms that control the behavior of S–L interfaces in materials.

This book deals with in situ dynamic observation and analysis of heterogeneous catalysis using environmental cells (EC) in transmission (TEM) and scanning electron microscopes (SEM). In general, it is based on outstanding and unique works carried out by the authors themselves over the past three decades, who pioneered this key enabling area of materials science.

An experimental high-resolution image of a solid–liquid interface of solid Si and liquid Al–Si alloy has been compared with theoretical images obtained by computer simulation. It has been concluded that the solid–liquid interface has a transition layer, the structure of which is compatible with the 1 × 1 Si-{111} surface.

The atomic structure and dynamic behavior of the solid-liquid interface of alumina were observed in a transmission electron microscope (TEM). The in-situ heating experiment of the alumina powder was performed using the newly developed heating holder. The surface of alumina was partially melted at about 2000K. Molten alumina on the surface migrated along the surface and formed liquid droplets. Such droplets existed stably on the surface during observation. The solid-liquid interface was observed by high resolution electron microscopy. The layer-by-layer growth of solid was observed on the solid-liquid interface. The nucleation of the monolayer island and the progress of the atomic step were observed directly. The velocity of the step progress at the solid-liquid interface was directly measured.