Water-based synthesis of zeolitic imidazolate framework-8 for CO₂ capture

Abstract

a This paper studies the impacts of five key synthesis parameters of zeolitic imidazolate framework-8 (ZIF-8) in an aqueous solution, namely zinc resource, pH value, temperature, reaction time, and the concentration of water in the ligand (H 2 O/Hmim). It was found that the crystallization of ZIF-8 samples is strongly impacted by these synthesis parameters. ZIF-8 synthesized at a temperature of 85 C, reaction time of 5 min, and pH value of 11.4 had a large special surface area and pore volume, and thus had a high CO 2 adsorption capacity of 3.04 mmol g À1. The CO 2 capture capacity remained constant after eleven consecutive adsorption-desorption experiments. Further applications of the hydrothermal synthesis method are promising considering the remarkable CO 2 adsorption capacity and cyclic regeneration ability.

Facile and Green Synthesis of Starfruit-Like ZIF-L, and Its Optimization Study

“…The reaction times of 30 and 60 min were still in the crystal growth phase, such that the formation of ZIF-L had not been completed. Previous studies reported that the ZIF’s characteristics in terms of surface area and pore volume increased during the crystal growth phase until a certain time, and then remained constant [ 2 , 20 ]. However, Figure 2 shows the decreased value of ZIF-L synthesized for a reaction time of 180 min.…”

“…The highest value was obtained at a temperature of 30 °C. A previous study reported that ZIFs with a high crystallinity and surface area could be obtained at a specific temperature [ 20 ]. The crystallinity and surface area were the main characteristics that affected the value.…”

“…They have a crystalline structure, large surface area, high pore volume, tunable pore size, good adsorption capacity, good thermal and chemical stability, and flexibility, and are easy to functionalize and modify [ 4 , 5 , 6 , 7 , 8 ]. Due to their outstanding characteristics, they have been applied in many applications, such as selective adsorption [ 9 , 10 , 11 ], water and wastewater treatments [ 12 , 13 , 14 ], composite constituents [ 15 , 16 ], catalysts and photocatalysts [ 17 , 18 ], fluorescence sensors [ 1 , 19 ], gas storage and separation [ 20 , 21 ], and drug delivery [ 22 , 23 ]. In the last few decades, many types of MOFs have been studied and developed through various synthesis methods, including diffusion, solvo(hydro)thermal, microwave, electrochemical, mechanochemical and sonochemical methods [ 24 ].…”

“…This allows the ZIF-8 to have a rhombic dodecahedron crystal shape [ 1 , 3 , 25 , 27 ]. However, it did not rule out the formation of other crystal shapes, such as hexagonal [ 15 , 28 ], truncated cubic [ 26 ], spherical [ 29 ], rod-like, and cylindrical crystal shapes [ 20 ]. This phenomenon may occur due to differences in the method, parameters and modulator addition.…”

Rapid and Scalable Synthesis of Zeolitic Imidazole Framework (ZIF‐8) and its Use for the Detection of Trace Levels of Nitroaromatic Explosives

“…Recently, considerable efforts have been devoted to synthesize ZIF‐8 in green and facile, for example in an aqueous medium at room temperature . Shi et al reported that synthesis of ZIF‐8 in an aqueous medium is highly influenced by zinc source, pH, temperature, reaction time, and concentration of water in the ligand . Pan et al reported synthesizing ZIF‐8 in 5 min, in an aqueous medium, with a microporous volume of about 0.31 cm 3 g −1 .…”