Electrostatic Self-Assembled Synthesis of Amorphous/Crystalline g-C 3 N 4 Homo-Junction for Efficient Photocatalytic H 2 Production with Simultaneous Antibiotic Degradation.

g-C 3 N 4 has been regarded as a promising photocatalyst for photo-reforming antibiotics for H 2 production but still suffers from its high charge recombination, which has been proven to be solvable by constructing a g-C 3 N 4 homo-junction. However, those reported methods based on uncontrollable calcination for preparing a g-C 3 N 4 homo-junction are difficult to reproduce. Herein, an amorphous/crystalline g-C 3 N 4 homo-junction (ACN/CCN) was successfully synthesized via the electrostatic self-assembly attachment of negatively charged crystalline g-C 3 N 4 nanorods (CCN) on positively charged amorphous g-C 3 N 4 sheets (ACN). All the ACN/CCN samples displayed much higher photo-reforming of antibiotics for H 2 production ability than that of pristine ACN and CCN. In particular, ACN/CCN-2 with the optimal ratio exhibited the best photocatalytic performance, with a H 2 evolution rate of 162.5 μmol·g -1 ·h -1 and simultaneous consecutive ciprofloxacin (CIP) degradation under light irradiation for 4 h. The UV-vis diffuse reflectance spectra (DRS), photoluminescence (PL), and electrochemical results revealed that a homo-junction is formed in ACN/CCN due to the difference in the band arrangement of ACN and CCN, which effectively suppressed the charge recombination and then led to those above significantly enhanced photocatalytic activity. Moreover, H 2 was generated from the water reduction reaction with a photogenerated electron (e - ), and CIP was degraded via a photogenerated hole (h + ). ACN/CCN exhibited adequate photostability and reusability for photocatalytic H 2 production with simultaneous CIP degradation. This work provides a new idea for rationally designing and preparing homo-junction photocatalysts to achieve the dual purpose of chemical energy production and environmental treatment.