▎ 摘　　要

The importance of hydrogen peroxide (H2O2) determination has been rapidly increasing due to its significant usage in biological and industrial applications. Hence, highly sensitive and selective sensors are required for H2O2 determination. This work demonstrates the development of highly sensitive electrochemical H2O2 sensors by using a spray exfoliated graphene and porous cobalt hexacyanoferrate nanosphere (Gr/P-CoHCF-NSPs) composite. The liquid phase high-pressure spray exfoliation technique was used to exfoliate high-quality graphene for electrochemical sensing applications. The EDTA chelation strategy was used for the homogeneous formation of P-CoHCF-NSPs on spray exfoliated graphene surfaces. The large electroactive surface area and excellent electron transfer ability of spray exfoliated graphene significantly enhanced the H2O2 sensing ability of the composite. The synthesized Gr/P-CoHCF-NSPs composite is highly reactive towards the oxidation of H2O2. The sensitivity of the fabricated sensor was 914 mu A mM(-1) cm(-2) in a linearity range of 1 to 1000 mu M. The LOD of the fabricated sensors was around 1 mu M. Comparing the fabricated sensors with recently developed H2O2 sensors indicates a significant improvement in sensitivity and LOD. The interference study of the fabricated sensors revealed their highly selective nature towards H2O2 sensing. The recovery and real sample analysis of the fabricated sensors confirmed that the Gr/P-CoHCF-NSPs based H2O2 sensors are potential candidates for H2O2 detection in real samples.