Enhanced visible light photocatalytic activity and mechanism of BiPO4 nanorods modified with AgI nanoparticles

• AgI modified BiPO4 was synthesized by deposition–precipitation method.
• AgI nanoparticles dramatically enlarged the visible light absorption of BiPO4.
• AgI/BiPO4 exhibited higher photocatalytic activity than AgI and BiPO4.
• BiPO4 acted as an electron trap in the separation process of photocarriers.

A novel visible-light-driven AgI/BiPO4 composite was synthesized by a facile room temperature deposition–precipitation method. The structures, morphologies, components and optical properties of the obtained samples were systematically characterized using X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, UV–vis diffuse reflectance spectroscopy and Brunauer–Emmett–Teller surface area. The loading of AgI nanoparticles endowed BiPO4 with good visible light absorption and excellent visible light photocatalytic activity for degrading rhodamine B. The kapp value of AgI/BiPO4 for degrading rhodamine B was 0.044 min−1, which was three times that of pure AgI. Besides, AgI/BiPO4 maintained good stability in the recycling process. The outstanding photocatalytic activity could be mainly attributed to the fast separation of electron–hole pairs, ensured by the enhanced photocurrent intensity, by using BiPO4 as a highly efficient electron trap.

The novel AgI/BiPO4 composite synthesized by deposition–precipitation method presented excellent photocurrent intensity, photocatalytic activity as well as stability under visible light irradiation (λ > 420 nm) owing to the good visible light absorption and efficient electron–holes separation via BiPO4 electron trapping role.Figure optionsDownload high-quality image (170 K)Download as PowerPoint slide