Template-derived high surface area λ-MnO2 for supercapacitor applications

• Published in: Journal of applied electrochemistry 2014, Vol.44 (1), p.123-132
• Main Authors: Matei Ghimbeu, Camelia, Malak-Polaczyk, Agnieszka, Frackowiak, Elzbieta, Vix-Guterl, Cathie
• Format: Article
• Language: English
• Subjects: Chemical Sciences; Chemistry; Chemistry and Materials Science; Electrochemistry; Industrial Chemistry/Chemical Engineering; Material chemistry; Physical Chemistry; Research Article
• ISSN: 0021-891X; 1572-8838
• DOI: 10.1007/s10800-013-0614-6

The synthesis of lambda-manganese oxide (λ-MnO 2 ) with a developed porosity and an ordered and interconnected pore structure used as supercapacitor electrode is reported for the first time in the present study. A spinel-type LiMn 2 O 4 material was first prepared by hard-templating pathway using KIT-6 mesoporous silica as a template and metal nitrates as precursors, which was subsequently acid treated leading to λ-MnO 2 material. The materials exhibit high surface area (up to 150 m 2  g −1 ), defined pore size distribution with three-dimensional interconnected pores, and crystalline pore walls. The material textural properties as well as the morphologies vary considerably with the synthetic conditions. The as-synthesized porous λ-MnO 2 materials exhibit a noticeably better performance (120 F g −1 ) at high constant currents (1 A g −1 ) than commercial derived λ-MnO 2 (11 F g −1 ). The extended surface area and the porous and three-dimensional interconnected structures along with the specific morphology significantly enhance the lithium diffusion through the particles and allow for a more effective use of this pseudocapacitive material as an electrode in supercapacitor. Graphical Abstract