Preparation and Application of Ca0.8 Sr0.2 TiO3 for Plasma Activation of CO2

Abstract

Despite a large interest in plasma-assisted catalytic technology (PACT), very little has been reported about the catalytic effects of different dielectric barriers on a dielectric barrier discharge (DBD) reaction. In the present study, Ca 0.8 Sr 0.2 TiO 3 , that possesses a high permittivity, was prepared by liquid phase sintering and used as a dielectric barrier in a DBD reactor to break CO 2 . The mechanical and dielectric properties of Ca 0.8 Sr 0.2 TiO 3 were greatly enhanced by adding 0.5 wt.% Li 2 Si 2 O 5 . A DBD plasma was successfully generated by using this Ca 0.8 Sr 0.2 TiO 3 as a dielectric barrier and 18.8% CO 2 conversion was achieved with the residence time of 0.17 s at the frequency of 8 kHz, which was much higher than with those using an alumina or a silica glass barrier. It was found that the plasma power increased with the increasing of the permittivity, and finally very dense and strong microdischarges were initiated to decompose CO 2 .

Investigation of dielectric barrier discharge dependence on permittivity of barrier materials

“…5 Moreover, it was employed to break down CO 2 efficiently by a DBD plasma. 6,7 Comparative studies showed that the CO 2 reactivity increased with increasing relative permittivity of the barrier materials and both of them followed the sequence Ca 1−x Sr x TiO 3 ӷ alumina ͑Al 2 O 3 ͒ ജ silica glass ͑SiO 2 ͒. 6,7 However, our recent in-depth study showed an existence of an optimum permittivity for the barrier materials to generate dense and strong current pulses.…”

“…4 We have developed a dielectric barrier material, Ca 1−x Sr x TiO 3 with Li 2 Si 2 O 5 additive, which has a high relative density, a high dielectric constant, and a high dielectric strength. [5][6][7] This ceramic was used as dielectric barriers to ignite dense and strong plasma with high energy. 5 Moreover, it was employed to break down CO 2 efficiently by a DBD plasma.…”

Recent advances in the photocatalytic reduction of carbon dioxide

“…However, since C in the CO 2 exhibits the highest oxidation state, the CO 2 itself is chemically stable, and the standard Gibbs free energy (DG h ) of CO 2 is -394.39 kJ mol -1 (Dean 1998), which means CO 2 is a kind of inert molecule and is difficult for activation. To react with other molecules, the kinetics inertia and thermodynamics energy barrier should be overcome, which generally requires employing high temperature (Balucan and Dlugogorski 2012), high pressure (Liu et al 2013c) and using catalysts (Drees et al 2012;Ashley and O'Hare 2013), including coordinating activation (Huff et al 2012;Vogt et al 2012), Lewis acidbase synergistic activation (Ashley et al 2009;Mömming et al 2009), photoelectric activation (Jing et al 2013), biological enzyme catalytic activation (Kumar et al 2010) and plasma activation (Li et al 2006), etc.…”

Characteristics of the Decomposition of CO2 in a Dielectric Packed-Bed Plasma Reactor

“…Suib et al [16][17][18] have conducted a series of study on CO 2 decomposition in AC glow discharge reactors, and investigated the various influence factors such as metal catalysts, discharge parameters and additional gases. Li et al [19][20][21][22] have used Ca x Sr (1-x) TiO 3 as barrier materials in the decomposition of CO 2 in dielectric barrier discharge (DBD) plasma, and investigated the relation between the microdischarges and the permittivity of the barrier materials. It was found that Ca 0.8 Sr 0.2 TiO 3 with 0.5 wt% Li 2 Si 2 O 5 as dielectric barrier is optimum to obtain a steady discharge state and an efficient decomposition of CO 2 .…”