Electrochemical performance of ruthenium nanoparticles decorated on nitride carbon for non-enzymatic detection of hydrogen peroxide

Abstract

Development of high-performance Pt-free non-enzymatic hydrogen peroxide (H₂O₂) sensors on the basis of supported metal nanoparticles (NPs) is important for industrial and biological applications. Here, we report the preparation of ultrafine, surface-clean, and well-distributed Ru NPs and concomitant formation of nitride carbon (Ru/NC) by pyrolyzing tris(2,2′-bipyridyl)ruthenium(II) chloride (TBRC) with carbon. The use of the nitrogen (N)-containing Ru complex of TBRC as the metal precursor is essential for the preparation of ultrafine and highly dispersed Ru NPs (1.20 nm in diameter) on a NC support. The as-synthesized Ru/NC-800 displays superior analytical performance for non-enzymatic detection of H₂O₂ with a low detection limit of 0.468 μM, high sensitivity of 698 μA mM⁻¹ cm⁻², excellent linear detection ranging from 0.001 to 10.000 mM, good stability, and high selectivity. The control experiment results indicate that the high-performance of Ru/NC-800 must be ascribed to the ultrasmall and highly dispersed Ru NPs and N-doping, which can supply a higher density of active sites available for H₂O₂ detection. This study provides a facile strategy to synthesize ultrafine metal NPs and for concomitant production of NC for electrocatalytic non-enzymatic sensing.