Photothermal conversion-enabled temperature modulation for the growth of complex polymorphic architectures of calcium carbonate

Abstract

As a highly efficient and eco-friendly heat generation approach, the photothermal conversion process has been applied to many important areas such as desalination and medical treatments. We explored in this work the application of the photothermal conversion process for the fabrication of complex polymorphic calcium carbonate (CaCO₃) structures. Through stepwise temperature modulation enabled by photothermal conversion, architectures of aragonite@calcite, calcite@aragonite, and calcite@aragonite@calcite that are composed of multiple polymorphic phases were obtained. The different polymorphic phases on the same architectures are confirmed by confocal Raman micro-spectroscopy analysis. Further modification of the substrates with a patterned self-assembled monolayer through soft lithography enabled the growth of arrays of the complex polymorphic CaCO₃ structures on the surface. This study provides an efficient and promising methodology for thermally controlling the growth of materials with desired multi-phases and multi-functionalities for different applications.