Preparation and characterization of laser-irradiation induced amorphous for Ge2Sb2Te5 phase-change materials

Abstract

It has been a challenge to fully understand the structural characteristics of laser-irradiation induced amorphous (L-a) Ge 2 Sb 2 Te 5 (GST) alloy due to the difficulties of collecting diffraction data from high purity specimens. In this paper, by fabricating GST thin films on different substrates, we exhibit an effective way of preparing L-a GST dots in submicron scale on various types of specially designed transmission electron microscope (TEM) grids. The structural characteristics of L-a GST in the form of pair distribution functions (PDF) can be achieved on single dots of L-a GST via selected area electron diffraction (SAED). This general approach would be convenient for precisely producing laser-irradiation induced materials in submicron scale for structural investigation.laser-irradiation induced amorphous, Ge 2 Sb 2 Te 5 , TEM grid, laser pulse, pair distribution function Citation:Zhang L, Huang H, Yan Z G, et al. Preparation and characterization of laser-irradiation induced amorphous for Ge 2 Sb 2 Te 5 phase-change materials.

Transition metal nitride catalysts for selective conversion of oxygen-containing molecules

“… 17,147–152 In particular, studies showing production of C 2+ alcohols from syngas on Fe 2 N, Fe 3 N, and Fe 4 N catalysts 147 and C 2+ olefin synthesis from syngas on γ-Mo 2 N 149 represent promising demonstrations of the C–C coupling activity of TMN catalysts. Additionally, CO has been utilized in investigations to probe the Pt-like properties of the surface sites of Mo 2 N. 152,153 These studies have identified the promising activity of TMNs for the upgrading of CO, but significant efforts are needed to improve the yield and selectivity of desired products.…”

“…17 While Fe-, Co-, Ni-, and Ru-based materials are the most common catalysts for Fischer-Tropsch synthesis, studies over the past decade have identied several TMN catalysts with promising activity and selectivity for CO utilization reactions. 17,[147][148][149][150][151][152] In particular, studies showing production of C 2+ alcohols from syngas on Fe 2 N, Fe 3 N, and Fe 4 N catalysts 147 and C 2+ olen synthesis from syngas on g-Mo 2 N 149 represent promising demonstrations of the C-C coupling activity of TMN catalysts. Additionally, CO has been utilized in investigations to probe the Pt-like properties of the surface sites of Mo 2 N. 152,153 These studies have identied the promising activity of TMNs for the upgrading of CO, but signicant efforts are needed to improve the yield and selectivity of desired products.…”

Toward structural/chemical cotailoring of phase‐change Ge–Sb–Te in a transmission electron microscope

“…It is known that the thermal and electrical fields are the two main routes to modify structure and properties of Ge-Sb-Te materials. Amorphous Ge 2 Sb 2 Te 5 can be crystallized into rocksalt-type Ge 2 Sb 2 Te 5 when the temperature increases (Kooi et al, 2004) or electron/laser irradiation (Kooi et al, 2004;Zhang et al, 2011;Zhou et al, 2013) is conducted. However, such structural transition is usually accompanied without modification of chemical composition.…”