Large Cs adsorption capability of nanostructured Prussian Blue particles with high accessible surface areas

Abstract

Very recently, we have reported preparation of several types of Prussian Blue (PB) particles with varying particle sizes by systematically tuning the synthetic conditions (Angew. Chem., Int. Ed., 2012, 51, 984–988). Here, the obtained PB particles are used for removal of Cs ions from aqueous solutions, which will be useful for remediation of nuclear waste. To evaluate the uptake ability of Cs ions into the PB particles, we utilize quartz crystal microbalance (QCM) for real-time monitoring of uptake behavior of Cs ions into the PB particles. The frequency of the QCM is promptly decreased after injection of Cs ions solution into the QCM cell. Hollow PB nanoparticles of 190 nm in diameter have very high surface area (338 m² g⁻¹), in comparison with other PB particles, leading to efficient Cs adsorption capability eight times larger than that of the commercial PB particles. The diffusion in terms of dissociation constant (K_d), maximum amount of adsorbed Cs in PB particles (m_max), and the adsorption kinetics (k) of Cs ions into the PB particles are also discussed. Due to the selective uptake for Cs ions based on K_d and k values, the PB particles can be proposed as good candidates in waste management consideration.