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.