Exfoliation of a Two-Dimensional Metal-Organic Framework for Enhanced Photocatalytic CO₂ Reduction

A two-dimensional metal-organic framework,FICN-12,was synthesized and tested for photocatalytic CO2 reduction.Exfoliation of FICN-12 into monolayer and few-layer nanosheets exposesmore catalytic sites and increases its catalytic activity. The nanosheetsshowed photocatalytic CO and CH4 production rates nearly1.4 times higher than those of bulk FICN-12. A two-dimensional metal-organic framework, FICN-12,wasconstructed from tris-[4-(1H-pyrazole-4-yl)-phenyl]-amine(H(3)TPPA) ligands and Ni-2 secondary buildingunits. The triphenylamine moiety in the H(3)TPPA ligand readilyabsorbs UV-visible photons and sensitizes the Ni center todrive photocatalytic CO2 reduction. FICN-12 can be exfoliatedinto monolayer and few-layer nanosheets with a "top-down"approach, which exposes more catalytic sites and increases its catalyticactivity. As a result, the nanosheets (FICN-12-MONs) showed photocatalyticCO and CH4 production rates of 121.15 and 12.17 mu mol/g/h,respectively, nearly 1.4 times higher than those of bulk FICN-12.