Preparation and Gas Adsorption Studies of Three Mesh-Adjustable Molecular Sieves with a Common Structure

Solvothermal reactions of a predesigned amphiphilic ligand, 4'-tert-butyl-biphenyl-3,5-dicarboxylate (BBPDC), with Zn(NO3)(2), Co(NO3)(2), and Cu(NO3)(2) gave rise to three isostructural mesh-adjustable molecular sieves (MAMSs), MAMS-2, MAMS-3, and MAMS-4, respectively. The three new MAMSs all exhibit temperature-tuned molecular sieving effect. There exists a linear relationship between mesh size and temperature, D = D-0 + alpha T (D, mesh size at temperature T K; D-0, mesh size at 0 K; and alpha, constant). Constants D-0 and alpha are characteristics of a ligand in a certain structure, independent of the choice of metal. As a result, all of the three MAMSs based on the BBPDC ligand have a D-0 of 2.83 and an a of 0.0073.