Biotemplating: a sustainable synthetic methodology for Na-ion battery materials

Abstract

Dextran biotemplating is a novel, sustainable and reduced-temperature synthetic approach that allows a high level of control over the size and shape of particles formed. This article discusses the application of this technique to the synthesis of an important candidate sodium-ion positive electrode material, Na_2/3Ni_1/3Mn_2/3O₂ (or ‘NNM’), with a high theoretical specific capacity (173 mA h g⁻¹). While a solid state reference sample prepared at 850 °C exhibited a specific capacity of ∼80 mA h g⁻¹ after 10 cycles, samples made via our dextran biotemplating route with final calcination at 550 °C for 12 h showed a large and significant improvement at 103.1 mA h g⁻¹, under the same operating conditions.