Maitra S, Mitra R, Nath T K
School of Nano-Science and Technology, Indian Institute of Technology Kharagpur, 721302, West Bengal, India.
J Nanosci Nanotechnol. 2021 Dec 1;21(12):6217-6226. doi: 10.1166/jnn.2021.19321.
Supercapacitor and hydrogen-based fuel cells are cheap and environmental-friendly next-generation energy storage devices that are intended to replace Lithium-ion batteries. Metal oxide nanostructures having perovskite crystal structure have been found to exhibit unique electrochemical properties owing to its unique electronic band structure and multiple redox-active ions. Herein, MgTiO₃ nanoparticles (MTO-1) were synthesized by wet-chemical sol-gel technique with an average particle size of 50-55 nm, which exhibited superior supercapacitor performance of capacitance () = 25 F/g (at 0.25 A/g), energy density () = 17 Wh/kg, power density () = 275 W/kg and 82.41% capacitance retention (after 1000 cycles). Aqueous 1 M Mg(ClO₄)₂ solution was used as the electrolyte. MTO-1 revealed an overpotential () = 1.329 V and Tafel slope () = 374 mV/dec towards Oxygen Evolution Reaction (OER) electrocatalyst and exhibited = 0.914 V and = 301.4 mV/dec towards Hydrogen Evolution Reaction (HER) electrocatalyst, both in presence of alkaline 1 M KOH solution, making these MgTiO₃ nanoparticles very promising for potential use in various technologically important electrochemical applications.
超级电容器和氢基燃料电池是廉价且环保的下一代储能装置，旨在取代锂离子电池。人们发现，具有钙钛矿晶体结构的金属氧化物纳米结构因其独特的电子能带结构和多种氧化还原活性离子而展现出独特的电化学性质。在此，通过湿化学溶胶 - 凝胶技术合成了平均粒径为50 - 55 nm的MgTiO₃纳米颗粒（MTO - 1），其在0.25 A/g电流密度下展现出25 F/g的优异超级电容器性能，能量密度为17 Wh/kg，功率密度为275 W/kg，且在1000次循环后电容保持率为82.41%。使用1 M Mg(ClO₄)₂水溶液作为电解质。在碱性1 M KOH溶液存在的情况下，MTO - 1作为析氧反应（OER）电催化剂时过电位为1.329 V，塔菲尔斜率为374 mV/dec；作为析氢反应（HER）电催化剂时过电位为0.914 V，塔菲尔斜率为301.4 mV/dec，这使得这些MgTiO₃纳米颗粒在各种具有重要技术意义的电化学应用中具有很大的应用潜力。
