Solvent-Directed Assembly and Transition-Metal Functionalization of a Two-Dimensional Indium Chalcogenide Framework

Area of Science:

• Materials Science
• Inorganic Chemistry
• Nanotechnology

Background:

• Two-dimensional (2D) chalcogenide frameworks offer tunable structures and flexibility.
• Current synthesis methods often require high temperatures, limiting material diversity.
• Mild synthesis conditions can unlock new materials and properties.

Purpose of the Study:

• To develop a generalizable strategy for constructing diverse indium sulfide frameworks under mild conditions.
• To explore postsynthetic functionalization of 2D chalcogenide frameworks.
• To evaluate the catalytic performance of modified frameworks for the oxygen evolution reaction (OER).

Main Methods:

• Amine- and solvent-directed synthesis strategy for 1D, 2D, and 3D indium sulfide frameworks.
• Solvent modulation to control framework dimensionality.
• Chloride-mediated etching and ion exchange for postsynthetic incorporation of transition metals (Fe, Co, Ni).

Main Results:

• Selective synthesis of 1D, 2D, and 3D indium sulfide frameworks from identical precursors.
• Successful postsynthetic incorporation of Fe, Co, and Ni ions into a 2D framework (T2-InS-AEP) while maintaining crystallinity.
• Ni- and Co/Ni-modified frameworks demonstrated significantly enhanced OER activity, reaching performance levels comparable to benchmark IrO₂.

Conclusions:

• A versatile amine- and solvent-directed approach enables the modular construction of indium sulfide frameworks.
• Postsynthetic modification allows for tuning of material properties and catalytic performance.
• This work provides a pathway for designing advanced 2D chalcogenide materials for energy applications like OER.