Conversion of CO2 into CO using plasma processing powered by renewable energy is a promising method to convert intermittent sustainable electricity into storable chemical energy.Despite extensive research efforts worl...Conversion of CO2 into CO using plasma processing powered by renewable energy is a promising method to convert intermittent sustainable electricity into storable chemical energy.Despite extensive research efforts worldwide,there is currently no process that achieves economically viable values for both CO2 conversion fraction and energy recovery efficiency simultaneously.Here we demonstrate that a process that utilizes the Boudouard reaction,CO^2++C→2 CO,driven by a thermal plasma allows both 95%CO2 conversion to CO and energy recovery efficiency of 70%,values far higher than seen so far.By comparing the conversion process with and without CO2 excitation by a plasma and by using optical emission spectroscopy we show that the improved performance is due to a novel mode of operation where CO2 is pyrolyzed into an active mixture of CO,O and O2 by an arc discharge which is then introduced into a fixed bed to interact with carbon material.In this way,the free oxygen in the mixture combusts with carbon to form CO,and residual plasma excited CO2 is reduced by carbon.In the overall process,the endothermic Boudouard reaction is partially replaced by an exothermic reaction,and the excess electric energy to produce CO2 plasma is reused in the carbon bed.展开更多
Experiments of CO_2 splitting by dielectric barrier discharge（DBD） plasma were carried out, and the influence of CO_2 flow rate, plasma power, discharge voltage, discharge frequency on CO_2 conversion and process en...Experiments of CO_2 splitting by dielectric barrier discharge（DBD） plasma were carried out, and the influence of CO_2 flow rate, plasma power, discharge voltage, discharge frequency on CO_2 conversion and process energy efficiency were investigated. It was shown that the absolute quantity of CO_2 decomposed was only proportional to the amount of conductive electrons across the discharge gap,and the electron amount was proportional to the discharge power; the energy efficiency of CO_2 conversion was almost a constant at a lower level, which was limited by CO_2 inherent discharge character that determined a constant gap electric field strength. This was the main reason why CO_2 conversion rate decreased as the CO_2 flow rate increase and process energy efficiency was decreased a little as applied frequency increased. Therefore, one can improve the CO_2 conversion by less feed flow rate or larger discharge power in DBD plasma, but the energy efficiency is difficult to improve.展开更多
This paper brings the comparison of performances of CO_(2)conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field,organised in an open access online database.This t...This paper brings the comparison of performances of CO_(2)conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field,organised in an open access online database.This tool is open to all users to carry out their own analyses,but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made,and ultimately to improve the efficiency of CO_(2)conversion by plasma-catalysis.The creation of this database and database user interface is motivated by the fact that plasma-catalysis is a fast-growing field for all CO_(2)conversion processes,be it methanation,dry reforming of methane,methanolisation,or others.As a result of this rapid increase,there is a need for a set of standard procedures to rigorously compare performances of different systems.However,this is currently not possible because the fundamental mechanisms of plasma-catalysis are still too poorly understood to define these standard procedures.Fortunately however,the accumulated data within the CO_(2)plasma-catalysis community has become large enough to warrant so-called“big data”studies more familiar in the fields of medicine and the social sciences.To enable comparisons between multiple data sets and make future research more effective,this work proposes the first database on CO_(2)conversion performances by plasma-catalysis open to the whole community.This database has been initiated in the framework of a H_(2)0_(2)0 European project and is called the“PIONEER Data Base”.The database gathers a large amount of CO_(2)conversion performance data such as conversion rate,energy efficiency,and selectivity for numerous plasma sources coupled with or without a catalyst.Each data set is associated with metadata describing the gas mixture,the plasma source,the nature of the catalyst,and the form of coupling with the plasma.Beyond the database itself,a data extraction tool with direct visualisation features or advanced filtering functionalities has been dev展开更多
COconversion via photocatalysis is a potential solution to address global warming and energy shortage.Photocatalysis can directly utilize the inexhaustible sunlight as an energy source to catalyze the reduction of COt...COconversion via photocatalysis is a potential solution to address global warming and energy shortage.Photocatalysis can directly utilize the inexhaustible sunlight as an energy source to catalyze the reduction of COto useful solar fuels such as CO, CH, CHOH, and CHOH. Among studied formulations, Cubased photocatalysts are the most attractive for COconversion because the Cu-based photocatalysts are low-cost and abundance comparing noble metal-based catalysts. In this literature review, a comprehensive summary of recent progress on Cu-based photocatalysts for COconversion, which includes metallic copper, copper alloy nanoparticles（NPs）, copper oxides, and copper sulfides photocatalysts, can be found. This review also included a detailed discussion on the correlations of morphology, structure, and performance for each type of Cu-based catalysts. The reaction mechanisms and possible pathways for productions of various solar fuels were analyzed, which provide insight into the nature of potential active sites for the catalysts. Finally, the current challenges and perspective future research directions were outlined, holding promise to advance Cu-based photocatalysts for COconversion with much-enhanced energy conversion efficiency and production rates.展开更多
The electrochemical conversion of carbon dioxide(CO_(2))has been attracting increasingly research interest in the past decade,with the ultimate goal of utilizing electricity from renewable energy to realize carbon neu...The electrochemical conversion of carbon dioxide(CO_(2))has been attracting increasingly research interest in the past decade,with the ultimate goal of utilizing electricity from renewable energy to realize carbon neutrality,as well as economic and energy benefits.Nonetheless,the capture and concentrating of CO_(2) cost a substantial portion of energy,while almost all the reported researches showed CO_(2) electroreduction under high concentrations of(typically pure)CO_(2) reactants,and only very few recent studies have investigated the capability of applying low CO_(2) concentrations(such as~10%in flue gases).In this work,we first demonstrated the electroreduction of 0.03%CO_(2)(in helium)in a homemade gas‐phase electrochemical electrolyzer,using a low‐cost copper(Cu)or nanoscale copper(nano‐Cu)catalyst.Mixed with steam,the gas‐phase CO_(2) was directly delivered onto the gas‐solid interface with the Cu catalyst and reduced to CO,without the need/constraint of being adsorbed by aqueous solution or alkaline electrolytes.By tuning the catalyst and experi‐mental parameters,the conversion efficiency of CO_(2) reached as high as~95%.Furthermore,we demonstrated the direct electroreduction of 0.04%CO_(2) from real air sample with an optimized conversion efficiency of~79%,suggesting a promising perspective of the electroreduction ap‐proach toward direct CO_(2) conversion.展开更多
Thermochemical two-step CO_(2) splitting is a potential approach that fixes the sustainable resource into transportable liquid fuels.However,the harsh CO_(2) splitting conditions,the limited oxygen release kinetics an...Thermochemical two-step CO_(2) splitting is a potential approach that fixes the sustainable resource into transportable liquid fuels.However,the harsh CO_(2) splitting conditions,the limited oxygen release kinetics and capacity of metal oxides block further promoted the CO yield and solar-to-fuel energy efficiency.Here,we propose a different carbon cycle assisted by Ni/La_(2)O_(3) via coupling methane decomposition with thermochemical CO_(2) splitting,replacing conventional metal oxides cycle.Superior performance was demonstrated with methane conversion reached around 94%with almost pure H_(2) generation.Encouragingly,CO_(2) conversion of 98%and CO yield of 6.9 mmol g^(-1) derived from CO_(2) were achieved,with peak CO evolution rate(402 mL min^(-1) g^(-1))of orders of magnitude higher than that in metal oxide process and outstanding thermodynamic solar-to-fuel energy efficiency(55.5%vs.18.5%).This was relevant to the synergistic activation of La_(2)O_(3) and Ni for CO_(2) in carbon cycle,thus improving CO_(2) splitting reaction with carbon species.展开更多
基金supported by the National Natural Science Foundation of China(Grants nos.11775155,51561135013,21603202)。
文摘Conversion of CO2 into CO using plasma processing powered by renewable energy is a promising method to convert intermittent sustainable electricity into storable chemical energy.Despite extensive research efforts worldwide,there is currently no process that achieves economically viable values for both CO2 conversion fraction and energy recovery efficiency simultaneously.Here we demonstrate that a process that utilizes the Boudouard reaction,CO^2++C→2 CO,driven by a thermal plasma allows both 95%CO2 conversion to CO and energy recovery efficiency of 70%,values far higher than seen so far.By comparing the conversion process with and without CO2 excitation by a plasma and by using optical emission spectroscopy we show that the improved performance is due to a novel mode of operation where CO2 is pyrolyzed into an active mixture of CO,O and O2 by an arc discharge which is then introduced into a fixed bed to interact with carbon material.In this way,the free oxygen in the mixture combusts with carbon to form CO,and residual plasma excited CO2 is reduced by carbon.In the overall process,the endothermic Boudouard reaction is partially replaced by an exothermic reaction,and the excess electric energy to produce CO2 plasma is reused in the carbon bed.
基金the support of National Natural Science Foundation of China(No.11375123)
文摘Experiments of CO_2 splitting by dielectric barrier discharge（DBD） plasma were carried out, and the influence of CO_2 flow rate, plasma power, discharge voltage, discharge frequency on CO_2 conversion and process energy efficiency were investigated. It was shown that the absolute quantity of CO_2 decomposed was only proportional to the amount of conductive electrons across the discharge gap,and the electron amount was proportional to the discharge power; the energy efficiency of CO_2 conversion was almost a constant at a lower level, which was limited by CO_2 inherent discharge character that determined a constant gap electric field strength. This was the main reason why CO_2 conversion rate decreased as the CO_2 flow rate increase and process energy efficiency was decreased a little as applied frequency increased. Therefore, one can improve the CO_2 conversion by less feed flow rate or larger discharge power in DBD plasma, but the energy efficiency is difficult to improve.
基金funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No.813393partially funded by the Portuguese FCT-Funda??o para a Ciência e a Tecnologia,under projects UIDB/50010/2020,UIDP/50010/2020 and PTDC/FIS-PLA/1616/2021。
文摘This paper brings the comparison of performances of CO_(2)conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field,organised in an open access online database.This tool is open to all users to carry out their own analyses,but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made,and ultimately to improve the efficiency of CO_(2)conversion by plasma-catalysis.The creation of this database and database user interface is motivated by the fact that plasma-catalysis is a fast-growing field for all CO_(2)conversion processes,be it methanation,dry reforming of methane,methanolisation,or others.As a result of this rapid increase,there is a need for a set of standard procedures to rigorously compare performances of different systems.However,this is currently not possible because the fundamental mechanisms of plasma-catalysis are still too poorly understood to define these standard procedures.Fortunately however,the accumulated data within the CO_(2)plasma-catalysis community has become large enough to warrant so-called“big data”studies more familiar in the fields of medicine and the social sciences.To enable comparisons between multiple data sets and make future research more effective,this work proposes the first database on CO_(2)conversion performances by plasma-catalysis open to the whole community.This database has been initiated in the framework of a H_(2)0_(2)0 European project and is called the“PIONEER Data Base”.The database gathers a large amount of CO_(2)conversion performance data such as conversion rate,energy efficiency,and selectivity for numerous plasma sources coupled with or without a catalyst.Each data set is associated with metadata describing the gas mixture,the plasma source,the nature of the catalyst,and the form of coupling with the plasma.Beyond the database itself,a data extraction tool with direct visualisation features or advanced filtering functionalities has been dev
基金financial supports from the National 1000 Young Talents Program of Chinathe National Nature Science Foundation of China (21603078)+1 种基金the National Materials Genome Project (2016YFB0700600)financial support from Research and Education in eNergy, Environment and Water (RENEW)Institute at the University at Buffalo, SUNY
文摘COconversion via photocatalysis is a potential solution to address global warming and energy shortage.Photocatalysis can directly utilize the inexhaustible sunlight as an energy source to catalyze the reduction of COto useful solar fuels such as CO, CH, CHOH, and CHOH. Among studied formulations, Cubased photocatalysts are the most attractive for COconversion because the Cu-based photocatalysts are low-cost and abundance comparing noble metal-based catalysts. In this literature review, a comprehensive summary of recent progress on Cu-based photocatalysts for COconversion, which includes metallic copper, copper alloy nanoparticles（NPs）, copper oxides, and copper sulfides photocatalysts, can be found. This review also included a detailed discussion on the correlations of morphology, structure, and performance for each type of Cu-based catalysts. The reaction mechanisms and possible pathways for productions of various solar fuels were analyzed, which provide insight into the nature of potential active sites for the catalysts. Finally, the current challenges and perspective future research directions were outlined, holding promise to advance Cu-based photocatalysts for COconversion with much-enhanced energy conversion efficiency and production rates.
文摘The electrochemical conversion of carbon dioxide(CO_(2))has been attracting increasingly research interest in the past decade,with the ultimate goal of utilizing electricity from renewable energy to realize carbon neutrality,as well as economic and energy benefits.Nonetheless,the capture and concentrating of CO_(2) cost a substantial portion of energy,while almost all the reported researches showed CO_(2) electroreduction under high concentrations of(typically pure)CO_(2) reactants,and only very few recent studies have investigated the capability of applying low CO_(2) concentrations(such as~10%in flue gases).In this work,we first demonstrated the electroreduction of 0.03%CO_(2)(in helium)in a homemade gas‐phase electrochemical electrolyzer,using a low‐cost copper(Cu)or nanoscale copper(nano‐Cu)catalyst.Mixed with steam,the gas‐phase CO_(2) was directly delivered onto the gas‐solid interface with the Cu catalyst and reduced to CO,without the need/constraint of being adsorbed by aqueous solution or alkaline electrolytes.By tuning the catalyst and experi‐mental parameters,the conversion efficiency of CO_(2) reached as high as~95%.Furthermore,we demonstrated the direct electroreduction of 0.04%CO_(2) from real air sample with an optimized conversion efficiency of~79%,suggesting a promising perspective of the electroreduction ap‐proach toward direct CO_(2) conversion.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB17020100)the National Key R&D Program of China(2016YFA0202-801)+1 种基金the National Natural Science Foundation of China(NSFC)grants(21676269,21706254,21878283,22022814)the Dalian Institute of Chemical Physics,CAS(DICP I201916)。
文摘Thermochemical two-step CO_(2) splitting is a potential approach that fixes the sustainable resource into transportable liquid fuels.However,the harsh CO_(2) splitting conditions,the limited oxygen release kinetics and capacity of metal oxides block further promoted the CO yield and solar-to-fuel energy efficiency.Here,we propose a different carbon cycle assisted by Ni/La_(2)O_(3) via coupling methane decomposition with thermochemical CO_(2) splitting,replacing conventional metal oxides cycle.Superior performance was demonstrated with methane conversion reached around 94%with almost pure H_(2) generation.Encouragingly,CO_(2) conversion of 98%and CO yield of 6.9 mmol g^(-1) derived from CO_(2) were achieved,with peak CO evolution rate(402 mL min^(-1) g^(-1))of orders of magnitude higher than that in metal oxide process and outstanding thermodynamic solar-to-fuel energy efficiency(55.5%vs.18.5%).This was relevant to the synergistic activation of La_(2)O_(3) and Ni for CO_(2) in carbon cycle,thus improving CO_(2) splitting reaction with carbon species.
