Bio‐Inspired Synthesis of Hematite Mesocrystals by Using Xonotlite Nanowires as Growth Modifiers and Their Improved Oxygen Evolution Activity

Abstract

Bio-inspired synthesis of functional materials with highly ordered structure and tunable properties is of particular interest, but efficient approaches that allow the access of these materials are still limited. We describe here a novel method for the preparation of hematite particles by using xonotlite nanowires (XNWs) as growth modifiers. The concentration of the XNWs has a profound effect on the final morphology of the products, while the concentration of the iron(III) ions can significantly control the size of the hematite particles. Moreover, the underlying mechanism of such XNWs modified bioinspired mineralization process has been proposed. Remarkably, the obtained hematite particles exhibit good oxygen evolution reaction (OER) catalytic performance. They can afford a current density of 10 mA cm-2 with an overpotential of 370 mV, a small Tafel slope of 65 mV decade-1 and show good stability in alkaline electrolyte. Such strategy preparing functional materials by using nanowires as the growth modifiers can be applied for constructing various materials with hierarchical structures and excellent performance in the future.