Interstitial N-doped SrSnO3 perovskite: structural design, modification and photocatalytic degradation of dyes†
Abstract
Structural design and modification are valuable approaches to tailor the electronic states of inorganic perovskites, which play a significant role in achieving state-of-the-art materials. Herein, an easy-to-manipulate, two-step, solid-state synthetic method is reported for the synthesis for nitrogen-doped SrSnO3 as a durable catalyst for the photocatalytic degradation of organic contaminants. In the synthetic procedure, urea acts as the nitriding source and nitrogen element is embedded into the crystal structure of SrSnO3, which changes its morphology; thus, helping SrSnO3 to convert from nanorods into nanoparticles via a simple solid-state synthetic technique. With the introduction of interstitial nitrogen atoms, the zero-dimensional SrSnO3 perovskite nanoparticles exhibited a kinetic reaction constant (0.040 min−1) of almost 10 times that of the one-dimensional SrSnO3 nanorods (0.004 min−1). When lowering the dimension, the advent of N in the lattice not only preserves the exposure of the higher active {001} planes, but also prolongs the activity of photo-induced carriers (number and lifetime), resulting in expected photocatalytic activity for the SrSnO3 nanocrystals. The catalytic mechanism was investigated via diffuse reflectance optical measurement and valence band XPS, which gave insight into how the interstitial N affects the structure and photocatalytic stability of the SrSnO3 perovskite. This study on low-dimensional SrSnO3 nanomaterials affords a way to investigate the charge carrier behavior and photochemical properties of perovskite materials.