Simple chemical trick boosts battery storage capacity by 16 percent
Researchers have developed a faster, cheaper way to manufacture zinc-based battery materials by adding nitrogen during synthesis rather than after. The technique produces batteries that charge quicker and store more energy—a significant advance for electric vehicles and grid storage that could reduce manufacturing costs and timelines.
Originaltitel: In-situ nitrogen doping of the ZnMn<sub>2</sub>O<sub>4</sub> framework via the combustion-gel method for Zn ion aqueous storage
<p>In this work, nitrogen was in situ doped into the spinel ZnMn<sub>2</sub>O<sub>4</sub> material via a one-step gel-combustion technique using various amounts of urea fuel. Despite the impurity ZnO and MnO phases at the higher amounts of urea fuel, the single-phase ZnMn<sub>2</sub>O<sub>4</sub> material was crystallized following the combustion reaction without the need for further treatment. The ZnMn<sub>2</sub>O<sub>4</sub> material synthesized at a molar ratio of urea fuel to total metal nitrate of 1:1 showed oxygen vacancies. However, 3.26 and 4.99 at.% N dopants were in-situ doped at a molar ratio of 2:1 and 3:1, respectively, as tracked by X-ray photoelectron and photoluminescence spectroscopy techniques. The combusted ZnMn<sub>2</sub>O<sub>4</sub> powders exhibited a porous microstructure, with the specific surface area and pore volume, decreasing from 78.6 to 12 m<sup>2</sup> g<sup>−1</sup> and from 0.27 to 0.04 cm<sup>3</sup> g<sup>−1</sup>, respectively, with an increase in the urea fuel content. The proper amount of N-dopants in the ZnMn<sub>2</sub>O<sub>4</sub> cathode material increased the charge storage capability, including a high-rate capability of 16% with increasing the current density from 50 to 1500 mA g<sup>−1</sup> and a high capacity retention of 76% at 1000 mA g<sup>−1</sup> over 500 cycles.</p>