Well-controlled preparation of evenly distributed nanoporous HOPG surface via diazonium salt assisted electrochemical etching process

Evenly distributed nanoporous highly oriented pyrolytic graphite (HOPG) surfaces with controllable pore size were successfully prepared via diazonium salt assisted electrochemical etching method. The porous HOPG was investigated by atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) Raman spectroscopy and X-ray diffraction. The size of these pores can be tuned by manipulating the electrochemical etching time. These porous HOPG substrates also demonstrated the enhanced electrocatalytical behaviour and were employed as benign arena for the immobilization of Ru(bpy)32+ for electrochemiluminescence (ECL) sensing applications.