▎ 摘　　要

Technical advancement in the field of ultra-small sensors and devices demands the development of novel micro-or nano-based architectures. Here we report the design and assembly of cross-linked three dimensional graphene nanoribbons (3D GNRs) using solution based covalent binding of individual 2D GNRs and demonstrate its electrochemical application as a 3D electrode. The enhanced performance of 3D GNRs over individual 2D GNRs is established using standard redox probes - [Ru(NH3)(6)](3+/2+), [Fe(CN)(6)](3-/4-) and important bio-analytes - dopamine and ascorbic acid. 3D GNRs are found to have high double layer capacitance (2482 mu F cm(-2)) and faster electron transfer kinetics; their exceptional electrocatalytic activity towards the oxygen reduction reaction is indicative of their potential over a wide range of electrochemical applications. Moreover, this study opens a new platform for the design of novel point-of-care devices and electrodes for energy devices.