The surface structure of manganese cation and MnTMPyP intercalated potassium niobate

K₄Nb₆O₁₇·3H₂O has a cation exchange ability in K⁺ ion existing in the interlayer and a property of photocatalyst host. As a preliminary step in the preparation of this catalyst, the cation exchange plays an important role. In this study, we prepared potassium niobate intercalated with Mn²⁺ and Mn(III)TMPyP⁷⁺ (Mn(III)5,10,15,20-tetra(4-pyridyl)-porphyrin) ions and observed the evidence of cation exchange in the interlayer by means of atomic force microscopy. AFM images showed that the Mn²⁺ ion and MnTMPyP cations regularly occupied the potassium sites. This indicates that the metallic oxide reduction center was formed in the interlayer by the cation exchanged species prior to redox treatment and not on the surface of the potassium niobate.