In-situ synthesis mechanism and high-efficiency photocatalytic activity of black Cu(I)/Cu(II) ultrathin nanosheets

Abstract

The introduction of cyan (CN–) typically requires toxic cyanides or the use of organometallic catalysts to catalyze CC bond cleavage in organics at high temperatures. Herein, the ultrathin cyano-bridged Cu(I)/Cu(II) polymer: {[Cu2(Py)5(CN)2](ClO4)}n (1), is in-situ synthesized under mild condition by catalyzing CC bond cleavage of 1,3-phenylenediacetonitrile. The synthesis mechanism of 1 demonstrates that CN– could be introduced from CC bond cleavage in benzyl cyanide catalyzed by simple copper compounds. Besides, the nanosheets of 1 has thickness about 0.322 nm, and it shows excellent photocatalytic activities (k = 3.17 mg. L-1.min−1 at pH = 4) for the degradation of methyl orange (MO) under visible light irradiation. The density functional theory (DFT) and electrospray mass spectrometry (ESI-MS) showed that the hydroxyl radical (·OH) first oxidizes the -NN- in the MO molecule, and ultimately generates CO2, H2O, and some small molecule acids.