CNTs synthesized with polyoxometalate-based metal-organic compounds as catalyst precursors via the CVD method and their adsorption performance for organic dyes

Successful production of carbon nanotubes (CNTs) were achieved via chemical vapor deposition (CVD) with four new polyoxometalate (POM)-based metal-organic compounds (MOCs) as catalyst precursors: {(4-H2bptzb)2)[HPMo12O40]2}·H2O (1), {Ag(4-H2bptzb)(H2O)[PMo12O40]} (2), {Ag3(3-bptzb)2[PMo12O40]} (3), {Ag4(3-bptzpe)3(H2O)2[HPMo12O40]2} (4), (3-bptzb = 1,4-bis(5-(3-pyridyl)tetrazolyl)-propane, 4-bptzb = 1,4-bis(5-(4-pyridyl)tetrazolyl)-propane, 3-bptzpe = 1,4-bis(5-(3-pyridyl)tetrazolyl)-pentane). The Mo2C nanoparticles transformed from the POM-based MOCs 1-4 acted as catalysts for the synthesis of CNT 1-4. The various specific surface areas of CNT 1-4 can be attributed to the content of Mo2C nanoparticles, which may be due to the diverse components and structures of compounds 1-4. The as grown CNTs exhibit high adsorption activity towards organic dyes methylene blue (MB), safranine T (ST) and organic dyes methylene orange (MO).