Supersaturation-Dependent Surface Structure Evolution: From Ionic, Molecular to Metallic Micro/Nanocrystals

Abstract

Deduced from thermodynamics and the Thomson-Gibbs equation that the surface energy of crystal face is in proportion to the supersaturation of crystal growth units during the crystal growth, we propose that the exposed crystal faces can be simply tuned by controlling the supersaturation, and higher supersaturation will result in the formation of crystallites with higher surface-energy faces. We have successfully applied it for the growth of ionic (NaCl), molecular (TBPe), and metallic (Au, Pd) micro/nanocrystals with high-surface-energy faces. The above proposed strategy can be rationally designed to synthesize micro/nanocrystals with specific crystal faces and functionality toward specific applications.

Morphology evolution of NaTaO3 submicrometer single-crystals: from cubes to quasi-spheres

“…While, CTC with high-energy {111} facets can be obtained at relatively high ratio of EG to water (i.e., high supersaturation). The morphology evolution of NaTaO 3 crystals from cube to CTC, then to ETC, and finally to spherical surfaces with other high-energy facets is well consistent with the strategy of supersaturation-dependent surface structure evolution [8].…”

“…Therefore, the exposed surfaces and the morphologies of crystallites can be controlled by varying the supersaturation of the crystal growth units. In our previous papers, it was discussed that the introduction of a poor solvent increased the supersaturation [8,20]. Inspired by these preceding reports, we introduced the supersaturation strategy into the controllable growth of NaTaO 3 crystal.…”

“…According to the Thomson-Gibbs equation, the surface energy of the crystal facets is in proportion to the supersaturation of the crystal growth units during the crystal growth under a supersaturated condition (not under an equilibrium condition) [8]. Therefore, the exposed surfaces and the morphologies of crystallites can be controlled by varying the supersaturation of the crystal growth units.…”

“…Establishing the mechanistic proposals on the basis of thermodynamics and kinetics principles and concepts, which are universal for the growth of macroscopic and microscopic crystals, is the first step towards a rational design and systematic approach [6,7]. Recently, based on thermodynamics and the Thomson−Gibbs equation, we concluded that the surface energy of crystal face is in proportion to the supersaturation of crystal growth units during the crystal growth, which can effectively guide the State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China * Corresponding authors (emails: zxxie@xmu.edu.cn (Xie Z); qkuang@xmu.edu.cn (Kuang Q)) control of the surface structure of some crystals [8].…”

Rational Design and Synthesis of Low-Temperature Fuel Cell Electrocatalysts

“…These studies found that periodic oxygen adsorption at high potentials and desorption at low potentials induce place exchange between oxygen and surface metal atoms, leading to the formation of HIFs. Considerable progress has also been made in the preparation of NCs with HIFs using wet-chemical synthesis through capping agents to stabilize low-coordinated sites or through controlling NC growth kinetics [14,[17][18][19][20][21].…”