Super Capacitors comprising Phosphonate and Arsenate-MOFs as active Electrode Materials

Electrochemical double layer capacitors (EDLCs) experience expanded ranges of applications as electrical storage units, based on their high power densities. It is estimated that their usage will further enhance common battery technologies, especially in the field of electric mobility. Besides their stability and conductivity, applied electrodes have to offer a great surface area for their mass in particular. Currently used materials like activated carbon reach values of 500 up to 1500 m²/g thus restricting further developments.

The invention presented here uses metal organic frameworks (MOFs) comprising phosphonic acid and arsonic acid metal binding units. Such MOFs provide engineerable surface areas with higher grades of customization compared to the conventional electrode materials. Phosphonate-MOFs are known to exhibit exceptional thermal and chemical stabilities while offering extremly rich structural variablity to optimize their surface area. Recent experiments proofed the semiconductive nature of phosphonate and arsonate-MOFs with band-gaps ranging between 1.4 and 2.7 eV and conductivities above 200 S/m. In combination with commonly used metallic centres made up of transition metals the constructon of trendsetting supercapacitors for everyday applications is made possible with a variety of customization options for specific demands.