Porous MnO₂/CNT catalysts with a large specific surface area for the decomposition of hydrogen peroxide

H₂O₂ vapor sterilization is an effective and safe method for removing various pathogens. To improve the efficiency of this technique, the time required for sterilization must be shortened. The aeration time constitutes a large portion of the total sterilization time; therefore, the development of a catalyst for H₂O₂ decomposition is necessary. Bulk MnO₂ is typically used in H₂O₂ decomposition, but it has a low specific surface area. To increase H₂O₂ decomposition activity, specific surface area and electron transfer ability of catalyst need improvement. In this study, MnO₂/CNT(x), where x denotes the weight ratio of CTAB to H₂O in the catalyst preparation, was synthesized using a soft template method with varying amounts of the template. Overall, the catalyst specific surface area remarkably increased to 190–200 m²/g from 0.043 m²/g for bulk MnO₂ and these increased surface areas resulted in superior H₂O₂ decomposition activity. Among the CNT-supported catalysts tested, MnO₂/CNT (1.0) exhibited the highest activity, which was 570 times that of bulk MnO₂. Aeration times were also calculated with some assumptions and the aeration can be finished within 1 hr (bulk MnO₂ needs about 25 hr).