Next-generation hydrogen peroxide sensors based on ordered carbonaceous frameworks derived from iron porphyrin

Carbon materials with ordered frameworks and atomically dispersed metal sites, referred to as ordered carbonaceous frameworks (OCFs), have attracted considerable attention for their promising potential in fundamental research and diverse practical applications, particularly in electrocatalysis. In this work, we synthesize Fe-incorporated OCF (Fe-OCF) with a heme-like structure through structure-preserving pyrolysis of Fe-porphyrin with four ethynyl groups. Fe-OCF is characterized by its ordered microporous framework, incorporating atomically dispersed Fe(III) sites with a high content of 6.9 wt%, analogous to metal-organic frameworks. At the same time, Fe-OCF possesses the advantages of carbon materials, including chemical stability, thermal stability, and electrical conductivity. Remarkably, Fe-OCF mimics the functionality of a sensor enzyme by facilitating the redox reaction of hydrogen peroxide, which is regulated by an applied potential, thereby enabling bidirectional catalytic behavior. Fe-OCF exhibits a linear reduction current response to hydrogen peroxide, underscoring its efficient electron transfer and catalytic properties. Moreover, Fe-OCF demonstrates superior stability compared to molecular Fe-porphyrin, further emphasizing its potential application as a novel hydrogen peroxide sensor. These results emphasize the significant potential of Fe-based OCFs as advanced materials for artificial enzyme applications and next-generation hydrogen peroxide sensing technology.