In situ co-pyrolysis fabrication of CeO2/g-C3N4 n–n type heterojunction for synchronously promoting photo-induced oxidation and reduction properties

Abstract

Development of efficient photocatalysts with both photoinduced oxidation and reduction properties is of great importance for environmental and energy applications. Herein, we report the fabrication of CeO₂/g-C₃N₄ hybrid materials by a simple in situ co-pyrolysis method using Ce(IO₃)₃ and melamine as precursors. The CeO₂/g-C₃N₄ composite catalysts possess outstanding photocatalytic activity for phenol degradation and NO removal under visible light irradiation. The degradation efficiency reaches up to 68.5 and 17.3 times higher than that of pure CeO₂ and g-C₃N₄, respectively. Significantly, it simultaneously exhibits an enhanced hydrogen production rate, which is 1.5 times that of the pure g-C₃N₄. The highly enhanced photo-induced oxidation and reduction activity could be attributed to the construction of a CeO₂/g-C₃N₄ n–n type heterojunction established by our in situ co-pyrolysis route, which enables intimate interaction across the phase interfaces; this facilitates separation and transfer of photoexcited charge carriers. This study could not only provide a facile and general approach to the fabrication of high-performance carbon-nitride-based photocatalytic materials, but also increase our understanding further on designing new hybrid composite photocatalysts for multi-functional applications.