Metal ion assistant transformation strategy to synthesize catechol-based metal–organic frameworks from Ti3C2Tx precursors

Chemical transformation strategy is capable of fabricating nanomaterials with well-defined structures and fascinating performance via controllable crystallization kinetics in the phase transformation. V 2 CT x MXene has been used as precursors to fabricate vanadium porphyrin metal–organic frameworks (V-PMOFs) via the coordination of deprotonated carboxylic acid ligands. However, the rational and in-depth exploration of synthesis mechanism with the aim of enriching the variety of MXene (i.e., Ti 3 C 2 T x ) and organic ligands (i.e., catechol-based) to design new MOFs is rarely reported. Herein, we have first developed a metal ion assistant transformation strategy to synthesize three-dimensional catechol-based TiCu-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) MOFs with a non-interpenetrating SrSi 2 ( srs ) framework using two-dimensional Ti 3 C 2 T x as precursors. The unique synergetic transformation mechanism involves the electron transfer from Ti 3 C 2 T x to electrostatically adsorbed Cu 2+ ion for redox reaction , the subsequent Ti–C bond rupture for Ti 4+ ion release , and the continuous chelation coordination between Ti 4+ /Cu 2+ and HHTP. Ti 3 C 2 T x precursors and auxiliary metal ion could be rationally substituted by V 2 CT x and M n + (e.g., Ni 2+ , Co 2+ , Mn 2+ , and Zn 2+ ), respectively. This strategy lays the foundation for the design and synthesis of innovative and multifarious MOFs derived from MXene or other unconventional metal precursors .