Electron-withdraw groups functionalized MOFs for efficient nitric oxide enrichment and simultaneous removal

Nitric oxide (NO) is one of the major pollutants in the air and the removal of dilute NO still faces challenges of low efficiency. Herein, an electron-withdraw groups functionalized metal-organic frameworks (MOFs) was reported as photocatalyst for the efficient removal of NO. The UiO-66 was conferred with nitro groups (-NO2), showing narrow band gap due to the conjugate with the electron cloud on the benzene ring, leading to deep color of this photocatalyst and high visible light sensitivity. Meanwhile, the electron acceptor -NO2 greatly increased the adsorption toward electron donor NO molecules. Resultingly, a high NO (550 ppb) removal rate of 83% and 76% were achieved under visible-light irradiation (λ > 400 nm) under dry and moist condition, respectively. This work provides a new strategy for the regulation of MOFs based photocatalysts, which may be applied in the treatment of air pollutants such as NO removal.