Plasmon Ag/Na-doped defective graphite carbon nitride/NiFe layered double hydroxides Z-scheme heterojunctions toward optimized photothermal-photocatalytic-Fenton performance

Three-dimensional flower-shaped plasmon Ag/Na-doped defective graphitic carbon nitride/NiFe layered double hydroxides (Ag/NaCNN/NiFe-LDH) Z-scheme heterojunction are fabricated by hydrothermal and calcination methods. The flower-shaped structure of NiFe-LDH enhances the multiple reflection and scattering of light, providing enough active sites to improve the utilization of sunlight. The introduction of Na-doped defects narrows the band gap of graphitic carbon nitride and accelerated the charge separation. Due to the surface plasmon resonance effect of Ag, Ag/NaCNN/NiFe-LDH shows excellent photothermal effect. The synergistic effect of photothermal-photocatalytic-Fenton reaction and Z-scheme heterojunction increased the hydrogen production of Ag/NaCNN/NiFe-LDH by 0.543 mmol h−1, which was 10 times higher than that of NiFe-LDH. The degradation efficiency of p-nitrophenol and bisphenol A under visible light was 99%. This simple strategy and reasonable design provide new ideas for the construction of Z-scheme heterojunction photocatalysts.