Development of a novel theory of pressure-induced nucleation in supercritical carbon dioxide

Abstract

Nucleation was the basis of the fabrication of two-dimensional materials in the bottom-up methods such as chemical vapor deposition and atomic layer deposition etc. Supercritical fluid deposition (SCFD) might provide...

Vapor–Liquid–Solid Growth of Site-Controlled Monolayer MoS2 Films Via Pressure-Induc ed Supercritical Phase Nucleation

“…Furthermore, the size of precursor particles was controlled by nucleation and growth processes . In the nucleation stage, higher pressure, temperature, and supersaturation were beneficial for nucleus formation . However, after the formation of the critical nucleus, the growth process was critical to the final particle size.…”

“…In our previous study, the formation of MoO 2 (acac) 2 critical nuclei was systematically investigated in relation to the nonideality of scCO 2 and supersaturation. 40 Therefore, we will focus on the growth behavior of critical nuclei and the deposition process in the following. The SEM images of MoO 2 (acac) 2 particles deposited on the sapphire at an initial temperature, pressure, and supersaturation of 50 °C, 20 MPa, and σ c = 5, respectively, are shown in Figure 2a, with a statistical average particle size (d p ) of ∼1.1 μm.…”

“…41 In the nucleation stage, higher pressure, temperature, and supersaturation were beneficial for nucleus formation. 40 However, after the formation of the critical nucleus, the growth process was critical to the final particle size. The nucleus continuously ″absorbed″ solute molecules and became larger or collided with other nuclei, leading to dissipation or agglomeration.…”

“…In our previous study, the formation of MoO 2 (acac) 2 critical nuclei was systematically investigated in relation to the nonideality of scCO 2 and supersaturation . Therefore, we will focus on the growth behavior of critical nuclei and the deposition process in the following.…”