Morphology‐Controlled Synthesis of Hierarchical Copper Hydroxyphosphate Microcrystals in Alkaline Buffer Solution and their Optical Properties

Abstract

AbstractA series of copper hydroxyphosphate (Cu2(OH)PO4) microcrystals with different shapes, including straw sheaf‐like microcrystals, microrods‐assembled microflowers, four‐edged arrow‐like microcrystals, and four‐pointed star‐like dendrites, are prepared by a hydrothermal method in Na2HPO4‐NaOH buffer solutions. The buffer solutions serve as both reactant and solvent. More importantly, the pH values of the alkaline buffer solutions significantly affect the morphologies of Cu2(OH)PO4 microcrystals. Four samples have absorption bands in the near‐ultraviolet, visible, and near‐infrared regions; furthermore, four Cu2(OH)PO4 microcrystals exhibit different band gap energies (3.06, 2.78, 2.68, and 2.39 eV) owing to their different structures. This strategy can be scaled up for the simple, green, and low‐cost production of Cu2(OH)PO4 microcrystals.