Syntheses and Structures of Two Reduced Open-framework Titanophosphates

Abstract

Using metallic Ti powder as raw materials and 1,2-diaminocyclohexane (DACH) as the trial template, two novel reduced titanophosphate open-structures were hydrothermally isolated by varying the H3PO4/H2O ratio to adjust the pH value. TiPO-1 crystallizes in orthorhombic Pbca space group with cell parameters a = 21.956(3) Å, b = 8.6268 (11) . TiPO-1 is constructed by infinite -Ti-O-Ti-O-linkage that is capped by PO4 groups to form a chain structure with protonated DACH molecules occupying the interchain spaces. TiPO-2 represents a rare 3-D reduced titanophosphate with 12-MR channels. The structure of TiPO-2 is a neutral framework with water molecules located in the channels.