Nanoscale p–n junction integration via the synergetic hybridization of facet-controlled Cu2O and defect-modulated g-C3N4-x atomic layers for enhanced photocatalytic water splitting

• Published in: Materials today energy 2022-10, Vol.29, p.101102, Article 101102
• Main Authors: Ng, Boon-Junn, Tang, Jie-Yinn, Ow, Liang Yin, Kong, Xin Ying, Ng, Yun Hau, Putri, Lutfi Kurnianditia, Chai, Siang-Piao
• Format: Article
• Language: English
• Subjects: Cuprous oxide; Graphitic carbon nitride; Hydrogen evolution; Nitrogen vacancy; Photocatalysis
• ISSN: 2468-6069; 2468-6069
• DOI: 10.1016/j.mtener.2022.101102

Tailoring multidimensional heterostructure interface in nanoscale with robust electronic configuration and regulated charge steering is of great significance for photocatalysis. In this contribution, an effective p–n heterojunction nanocomposites were formulated by hybridizing N-deficient g-C3N4 atomic layers (g-C3N4-x) and rhombic dodecahedral Cu2O with controlled facets. The concomitant outcomes from the p–n junction induce a built-in electric field that propel the atomic-level directional charge transfer and accommodate electrons and holes at separated locations of n-type g-C3N4-x and p-type Cu2O, respectively. This substantially enhances the electron–hole pairs separation and prolongs the lifetime of charge carriers. As a result, the best performing 3 wt% Cu2O/g-C3N4-x sample demonstrated an exceptional photocatalytic H2 evolution rate of 420.3 μmol/g/h under visible light irradiation, which is 1.8-fold augmentation in contrast to the individual counterpart (g-C3N4-x). In brief, this work presents a powerful strategy to modulate the interaction of heterointerface in achieving highly efficient photocatalytic application. [Display omitted] •Nanoscale p–n heterointerface featuring N-deficient g-C3N4 atomic layers and Cu2O.•Internal electric field at the depletion layer propels directional charge transfer.•Synergistic effect of p–n junction and midgap level for efficient electron trapping.