Time-Resolved CO2 Dissociation in a Nanosecond Pulsed Discharge

Martini, L.; Lovascio, Sara; Dilecce, Giorgio; Tosi, Paolo

doi:10.1007/s11090-018-9893-3

Cited by 35 publications

(86 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The best-fit CO2 concentration reduces to 9.4  0.1%, indicating a dissociation degree of only 4% of the CO 2 gas. This CO2 dissociation degree is close to the value reported from a pin-to-sphere configured ns-discharge [5,9] with a similar SEI (specific energy input) of 0.86 eV/molecule (calculated with mean pulse energy around 1mJ). Considering the small gas flow rate and the interchange between the discharge area and the background, the temperature and CO 2 concentration of the background gas are assumed to be constant in the overall afterglow with those at t = 0 s.…”

Section: Temporally Resolved Measurementsupporting

confidence: 86%

Time evolution of CO₂ ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy

Du¹,

Tsankov²,

Luggenhölscher³

et al. 2021

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

CO 2 dissociation stimulated by vibrational excitation in non-equilibrium discharges has drawn lots of attention. Ns-discharges are known for their highly non-equilibrium conditions. It is therefore of interest to investigate the CO 2 excitation in such discharges. In this paper, we demonstrate the ability for monitoring the time evolution of CO 2 ro-vibrational excitation with a well-selected wavelength window around 2289.0 cm -1 and a single CW quantum cascade laser (QCL) with both high accuracy and temporal resolution. The rotational and vibrational temperatures for both the symmetric and the asymmetric modes of CO 2 in the afterglow of CO 2 + He ns-discharge were measured with a temporal resolution of 1.5 s. The non-thermal feature and the preferential excitation of the asymmetric stretch mode of CO 2 were experimentally observed, with a peak temperature of T v3, max = 966  1.5 K, Tv12, max = 438.4  1.2 K and Trot = 334.6  0.6 K reached at 3 s after the nanosecond pulse. In the following relaxation process, an exponential decay with a time constant of 69 s was observed for the asymmetric stretch (001) state, consistent with the dominant deexcitation mechanism due to VT transfer with He and deexcitation on the wall. Furthermore, a synchronous oscillation of the gas temperature and the total pressure was also observed and can be explained by a two-line thermometry and adiabatic process. The period of the oscillation and its dependence on the gas components is consistent with a standing acoustic wave excited by the ns-discharge.

show abstract

Section: Temporally Resolved Measurementsupporting

confidence: 86%

Time evolution of CO₂ ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy

Du¹,

Tsankov²,

Luggenhölscher³

et al. 2021

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…In particular, the hydrogenation of CO 2 by technologies based on green electricity allows both the storage of renewable energy in value-added compounds and recycling CO 2 , thus paving the way to decarbonise the energy system. Non-thermal plasmas have been explored for their capability to activate very stable molecules with the potential of achieving a higher energy efficiency compared to purely thermal processes (Scapinello et al, 2016; Martini et al, 2018). To improve the performances and to control the outcome of plasma-based processes, insight into the physical and chemical mechanisms at play is desired.…”

Section: Introductionmentioning

confidence: 99%

State-Selected Reactivity of Carbon Dioxide Cations (CO2+) With Methane

et al. 2019

Self Cite

View full text Add to dashboard Cite

The reactivity of with CD 4 has been experimentally investigated for its relevance in the chemistry of plasmas used for the conversion of CO 2 in carbon-neutral fuels. Non-equilibrium plasmas are currently explored for their capability to activate very stable molecules (such as methane and carbon dioxide) and initiate a series of reactions involving highly reactive species (e.g., radicals and ions) eventually leading to the desired products. Energy, in the form of kinetic or internal excitation of reagents, influences chemical reactions. However, putting the same amount of energy in a different form may affect the reactivity differently. In this paper, we investigate the reaction of with methane by changing either the kinetic energy of or its vibrational excitation. The experiments were performed by a guided ion beam apparatus coupled to synchrotron radiation in the VUV energy range to produce vibrationally excited ions. We find that the reactivity depends on the reagent collision energy, but not so much on the vibrational excitation of . Concerning the product branching ratios ( / /DOCO + ) there is substantial disagreement among the values reported in the literature. We find that the dominant channel is the production of , followed by DOCO + and , as a minor endothermic channel.

show abstract

“…Or even a partial saturation of the dissociation may occur. Hopefully, advanced plasma diagnostics [23,[25][26][27] and future modelling efforts [7,28] will help understand the complex interplay of discharge physics and plasma chemistry in such non-equilibrium discharges.…”

Section: Discussionmentioning

confidence: 99%

CH4 reforming with CO2 in a nanosecond pulsed discharge. The importance of the pulse sequence

Montesano

Faedda

Martini

et al. 2021

Journal of CO2 Utilization

Self Cite

View full text Add to dashboard Cite

The plasma dry reforming reaction of methane with carbon dioxide is investigated in a nanosecond repetitively pulsed discharge, a type of plasma that offers some of the highest performance and non-equilibrium characteristics. The experiment's purpose was to examine the effect of varying the sequence of high-voltage pulses. We find that when successive pulses are closer than 500 μs, a memory-dominated regime gradually develops, which influences subsequent breakdown events. While reactant conversions increase with the plasma energy, both energy efficiency and conversions increase by shortening the inter-pulse time at the same plasma energy. This finding suggests that plasma power is not the only thing that matters to achieve better performance. How it is delivered can make a significant difference, in particular for CO2, whose conversion doubles at the maximum energy for molecule investigated, 1.6 eV molecule -1 .

show abstract

Time-Resolved CO2 Dissociation in a Nanosecond Pulsed Discharge

Cited by 35 publications

References 19 publications

Time evolution of CO₂ ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy

Time evolution of CO₂ ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy

State-Selected Reactivity of Carbon Dioxide Cations (CO2+) With Methane

CH4 reforming with CO2 in a nanosecond pulsed discharge. The importance of the pulse sequence

Contact Info

Product

Resources

About

Time-Resolved CO2 Dissociation in a Nanosecond Pulsed Discharge

Cited by 35 publications

References 19 publications

Time evolution of CO2 ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy

Time evolution of CO2 ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy

State-Selected Reactivity of Carbon Dioxide Cations (CO2+) With Methane

CH4 reforming with CO2 in a nanosecond pulsed discharge. The importance of the pulse sequence

Contact Info

Product

Resources

About

Time evolution of CO₂ ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy

Time evolution of CO₂ ro-vibrational excitation in a nanosecond discharge measured with laser absorption spectroscopy