Interfacially Modulated S‐Scheme Van der Waals Heterojunctional Photocatalyst for Selective CO2 Photoreduction Coupled with Organic Pollutant Degradation

Abstract

This study introduces a novel strategy employing a phosphate‐mediated S‐scheme 2D/2D Van der Waals heterojunction, xCu[acs]/yP‐BCN, linking copper phthalocyanine (CuPc) with boron‐doped and nitrogen‐deficient graphitic carbon nitride (BCN). By leveraging phosphate as a charge transfer mediator, spatial constraints are mitigated, facilitating efficient electron transition from BCN to CuPc upon excitation. The captured photoelectrons by CuPc central Cu2+ ion promote CO2 conversion into valuable products, boosting photocatalytic efficiency by 78‐fold compared to standalone BCN. In situ µs transient absorption spectroscopy quantitatively demonstrates a remarkable 36.4% electron transfer efficiency for CO2 reduction with xCu[acs]/yP‐BCN, surpassing other catalyst configurations. Additionally, a 4% CuPc integration into BCN substantially increases photodegradation efficiency of methylene blue (MB) to 96%, attributed to the heterojunction's ability to prevent charge carrier recombination. Moreover, under direct sunlight, the optimized heterostructure achieves a bisphenol‐A (BPA) photodegradation efficiency of approximately 70.6%, highlighting the potential of interface‐tailored photocatalysts in efficiently reducing CO2 and degrading environmental pollutants.