Atomically homogeneous dispersed ZnO/N-doped nanoporous carbon composites with enhanced CO2 uptake capacities and high efficient organic pollutants removal from water

Abstract

Advanced functional composite of ZnO nanoparticles embedded in N-doped nanoporous carbons has been synthesized by a simple one-step carbonization of zeolitic imidazolate framework-8 under a water stream atmosphere. A variety of characterization techniques show that the introduction of water steam during the carbonization process holds the key to obtain the fine and homogeneously dispersed ZnO nanoparticles within the functionalised nanoporous carbon matrix. Possessing a higher specific surface area, a larger pore volume and abundant oxygen-containing hydrophilic functional groups, the resulting composite exhibits a stronger interaction with CO 2 and is more efficient to promote the photocatalytic degradation-adsorption of methylene blue under visible light than the composite obtained without steam treatment. As a result, the steam derived composite exhibits increased CO 2 uptake capacity and excellent methylene blue molecules removal from water. Using different metal-organic frameworks as precursors, this new, simple and green method can be further expanded to generate various new homogeneous dispersed functional metal oxide/porous carbon composites with high efficient in relevant applications.

Effect of carbonization temperature on adsorption property of ZIF-8 derived nanoporous carbon for water treatment

“…ZIF-8 is one of mostly studied ZIFs, and has a molecular formula of Zn(2-methylimidazolate) 2 and sodaliterelated zeolitic structure; it is composed of six membered-ring pore windows (0.34 nm) and larger pores (1.14 nm) and has been reported as an adsorbent for the removal of various pollutants from water [31]. It is worth noting that ZIF-8 has fast adsorption rate and high adsorption capacity for the removal of benzotriazols from aqueous solutions [36]; however, this material has very low adsorption capacity for the removal of methylene blue dye from water.…”

“…For instance, nanoporous carbons derived from ZIF-67, MIL-100 and MOF-5 were prepared, and they had improved adsorption capacity for the removal of MB from water [1,37,38]. The nanoporous carbon was also obtained by carbonizing ZIF-8 at 800 C [2,39]. However, the methylene blue adsorption capacity of ZIF-M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 4 8-derived carbon was low (59 mg/g), which was because the carbonization temperature (800 C) was lower than the boiling point of Zn (908 C), limiting the surface area and pore volume of the nanoporous carbon [40,41].…”

“…Nanoporous carbon materials have promising characteristics such as high surface area, good chemical and thermal stabilities, fast kinetics as well as tendency to organic contaminants which makes them attractive for adsorption and separation applications [1,2]. For example, they have been used as supercapacitor [3][4][5], catalyst support [6][7][8] and adsorbent for hydrogen storage [9] as well as CO 2 capture [2,[10][11][12].…”

“…For example, they have been used as supercapacitor [3][4][5], catalyst support [6][7][8] and adsorbent for hydrogen storage [9] as well as CO 2 capture [2,[10][11][12]. In particular, they are widely used as adsorbents to remove organic and heavy metal contaminants from water in water treatment and purification [13][14][15][16][17][18].…”

1-butyl-3-methylimidazolium tetrafluoroborate functionalized ZnO nanoparticles for removal of toxic organic dyes

“…The incomplete degradation of such toxic chemicals and dyes by aerobic methods cause significant disturbance in aquatic life and hence pose a dangerous threat to aquatic animals [12][13][14][15][16][17][18]. Environmental scientists have adopted various approaches such as filtration, coagulation, flocculation, degradation, adsorption, and so on to overcome such dangerous threat [19][20][21].…”