Improving dispersion of indium polyphthalocyanine on carbon nanotube via molecular modification for efficient oxygen reduction to hydrogen peroxide

Abstract

Molecular catalysts have emerged as the promising candidate for oxygen reduction to hydrogen peroxide (H2O2). Dispersing homogeneously molecular catalyst on carbon support is the prerequisite for actual electrocatalysis application. Herein, we proposed a novel strategy of modification with sodium dodecylbenzenesulfonate (SDBS) to improve dispersion of indium polyphthalocyanine (InPPc) on carbon nanotube (CNT). The SDBS modification induces the matched surface hydrophilicity of CNT with InPPc, preventing InPPc aggregation. As a result, the InPPc/SDBS@CNT exhibits a remarkable onset potential of 0.84 V vs. RHE and selectivity of > 95 %, superior to InPPc/CNT and most recently reported catalysts. In situ Raman spectrum identifies the critical *OOH intermediate during H2O2 formation on InPPc/SDBS@CNT. Importantly, the InPPc/SDBS@CNT presents a prominent H2O2 production rate of 24.88 mg/cm2/h over 12 h in flow cell. This work provides an effective strategy to promote practical application of molecular catalysts.