Microbial electrosynthesis(MES) can potentially provide a mean for storing renewable energy surpluses as chemical energy. However, the fluctuating nature of these energy sources may represent a threat to MES, as the m...Microbial electrosynthesis(MES) can potentially provide a mean for storing renewable energy surpluses as chemical energy. However, the fluctuating nature of these energy sources may represent a threat to MES, as the microbial communities that develop on the biocathode rely on the continuous existence of a polarized electrode. This work assesses how MES performance, product generation and microbial community evolution are affected by a long-period(6 weeks) power off(open circuit). Acetogenic and H2-producing bacteria activity recovered after reconnection. However, few days later syntrophic acetate oxidation bacteria and H2-consuming methanogens became dominant, producing CH4 as the main product, via electromethanogenesis and the syntrophic interaction between eubacterial and archaeal communities which consume both the acetic acid and the hydrogen present in the cathode environment. Thus,the system proved to be resilient to a long-term power interruption in terms of electroactivity. At the same time, these results demonstrated that the system could be extensively affected in both end product generation and microbial communities.展开更多
Abiotic-biological hybrid systems that combine the advantages of abiotic catalysis and biotransformation for the conversion of carbon dioxide(CO2)to value-added chemicals and fuels have emerged as an appealing way to ...Abiotic-biological hybrid systems that combine the advantages of abiotic catalysis and biotransformation for the conversion of carbon dioxide(CO2)to value-added chemicals and fuels have emerged as an appealing way to address the global energy and environmental crisis caused by increased CO2 emission.We illustrate the recent progress in this field.Here,we first review the natural CO2 fixation pathways for an in-depth understanding of the biological CO2 transformation strategy and why a sustainable feed of reducing power is important.Second,we review the recent progress in the construction of abiotic-biological hybrid systems for CO2 transformation from two aspects:(i)microbial electrosynthesis systems that utilize electricity to support whole-cell biological CO2 conversion to products of interest and(ii)photosynthetic semiconductor biohybrid systems that integrate semiconductor nanomaterials with CO2-fixing microorganisms to harness solar energy for biological CO2 transformation.Lastly,we discuss potential approaches for further improvement of abiotic-biological hybrid systems.展开更多
Microbial electrosynthesis(MES)converts CO_(2)into value-added products such as volatile fatty acids(VFAs)with minimal energy use,but low production titer has limited scale-up and commercialization.Mediated electron t...Microbial electrosynthesis(MES)converts CO_(2)into value-added products such as volatile fatty acids(VFAs)with minimal energy use,but low production titer has limited scale-up and commercialization.Mediated electron transfer via H_(2)on the MES cathode has shown a higher conversion rate than the direct biofilm-based approach,as it is tunable via cathode potential control and accelerates electrosynthesis from CO_(2).Here we report high acetate titers can be achieved via improved in situ H_(2)supply by nickel foam decorated carbon felt cathode in mixed community MES systems.Acetate concentration of 12.5 g L^(-1)was observed in 14 days with nickel-carbon cathode at a poised potential of-0.89 V(vs.standard hydrogen electrode,SHE),which was much higher than cathodes using stainless steel(5.2 g L^(-1))or carbon felt alone(1.7 g L^(-1))with the same projected surface area.A higher acetate concentration of 16.0 g L^(-1)in the cathode was achieved over long-term operation for 32 days,but crossover was observed in batch operation,as additional acetate(5.8 g L^(-1))was also found in the abiotic anode chamber.We observed the low Faradaic efficiencies in acetate production,attributed to partial H_(2)utilization for electrosynthesis.The selective acetate production with high titer demonstrated in this study shows the H_(2)-mediated electron transfer with common cathode materials carries good promise in MES development.展开更多
The consumption of non-renewable fossil fuels has directly contributed to a dramatic rise in global carbon dioxide(CO_(2))emissions,posing an ongoing threat to the ecological security of the Earth.Microbial electrosyn...The consumption of non-renewable fossil fuels has directly contributed to a dramatic rise in global carbon dioxide(CO_(2))emissions,posing an ongoing threat to the ecological security of the Earth.Microbial electrosynthesis(MES)is an innovative energy regeneration strategy that offers a gentle and efficient approach to converting CO_(2) into high-value products.The cathode chamber is a vital component of an MES system and its internal factors play crucial roles in improving the performance of the MES system.Therefore,this review aimed to provide a detailed analysis of the key factors related to the cathode chamber in the MES system.The topics covered include inward extracellular electron transfer pathways,cathode materials,applied cathode potentials,catholyte pH,and reactor configuration.In addition,this review analyzes and discusses the challenges and promising avenues for improving the conversion of CO_(2) into high-value products via MES.展开更多
Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide,which is a greenhouse gas,to produce methane which acts as an energy source,without using organic substances.However,this bioel...Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide,which is a greenhouse gas,to produce methane which acts as an energy source,without using organic substances.However,this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic catalyst.When coupled with the oxidation of HS–to SO_(4)^(2-),methane production is thermodynamically more feasible,thus implying its production at a considerably lower applied voltage.In this study,we demonstrated the possibility of electrotrophic methane production coupled with HS–oxidation in a cost-effective bioanode chamber in the MES without organic substrates at a low applied voltage of 0.2 V.In addition,microbial community analyses of biomass enriched in the bioanode and biocathode were used to reveal the most probable pathway for methane production from HS–oxidation.In the bioanode,electroautotrophic SO_(4)^(2-)production accompanied with electron donation to the electrode is performed mainly by the following two steps:first,incomplete sulfide oxidation to sulfur cycle intermediates (SCI) is performed;then the produced SCI are disproportionated to HS^(–)and SO_(4)^(2-).In the biocathode,methane is produced mainly via H_(2)and acetate by electronaccepting syntrophic bacteria,homoacetogens,and acetoclastic archaea.Here,a new ecofriendly MES with biological H_(2)S removal is established.展开更多
Methane is produced in a microbial electrosynthesis system(MES) without organic substrates. However, a relatively high applied voltage is required for the bioelectrical reactions.In this study, we demonstrated that el...Methane is produced in a microbial electrosynthesis system(MES) without organic substrates. However, a relatively high applied voltage is required for the bioelectrical reactions.In this study, we demonstrated that electrotrophic methane production at the biocathode was achieved even at a very low voltage of 0.1 V in an MES, in which abiotic HS-oxidized to SO_(4)^(2-) at the anodic carbon-cloth surface coated with platinum powder. In addition, microbial community analysis revealed the most probable pathway for methane production from electrons. First, electrotrophic H_(2) was produced by syntrophic bacteria, such as Syntrophorhabdus, Syntrophobacter, Syntrophus, Leptolinea, and Aminicenantales, with the direct acceptance of electrons at the biocathode. Subsequently, most of the produced H_(2) was converted to acetate by homoacetogens, such as Clostridium and Spirochaeta 2. In conclusion,the majority of the methane was indirectly produced by a large population of acetoclastic methanogens, namely Methanosaeta, via acetate. Further, hydrogenotrophic methanogens,including Methanobacterium and Methanolinea, produced methane via H_(2).展开更多
基金the Spanish“Ministerio de Educación,Cultura y Deporte”for the predoctoral FPU Grant(FPU14/01573)the‘Ministerio de Economía y Competitividad’for the support of project ref:CTQ2015-68925-R(MINECO/FEDER,EU)。
文摘Microbial electrosynthesis(MES) can potentially provide a mean for storing renewable energy surpluses as chemical energy. However, the fluctuating nature of these energy sources may represent a threat to MES, as the microbial communities that develop on the biocathode rely on the continuous existence of a polarized electrode. This work assesses how MES performance, product generation and microbial community evolution are affected by a long-period(6 weeks) power off(open circuit). Acetogenic and H2-producing bacteria activity recovered after reconnection. However, few days later syntrophic acetate oxidation bacteria and H2-consuming methanogens became dominant, producing CH4 as the main product, via electromethanogenesis and the syntrophic interaction between eubacterial and archaeal communities which consume both the acetic acid and the hydrogen present in the cathode environment. Thus,the system proved to be resilient to a long-term power interruption in terms of electroactivity. At the same time, these results demonstrated that the system could be extensively affected in both end product generation and microbial communities.
文摘Abiotic-biological hybrid systems that combine the advantages of abiotic catalysis and biotransformation for the conversion of carbon dioxide(CO2)to value-added chemicals and fuels have emerged as an appealing way to address the global energy and environmental crisis caused by increased CO2 emission.We illustrate the recent progress in this field.Here,we first review the natural CO2 fixation pathways for an in-depth understanding of the biological CO2 transformation strategy and why a sustainable feed of reducing power is important.Second,we review the recent progress in the construction of abiotic-biological hybrid systems for CO2 transformation from two aspects:(i)microbial electrosynthesis systems that utilize electricity to support whole-cell biological CO2 conversion to products of interest and(ii)photosynthetic semiconductor biohybrid systems that integrate semiconductor nanomaterials with CO2-fixing microorganisms to harness solar energy for biological CO2 transformation.Lastly,we discuss potential approaches for further improvement of abiotic-biological hybrid systems.
基金supported by the Department of Energy Bioenergy Technologies Office under the award DE-EE0008932supported through the Princeton Center for Complex Materials(PCCM),a National Science Foundation(NSF)-MRSEC program(DMR-2011750).
文摘Microbial electrosynthesis(MES)converts CO_(2)into value-added products such as volatile fatty acids(VFAs)with minimal energy use,but low production titer has limited scale-up and commercialization.Mediated electron transfer via H_(2)on the MES cathode has shown a higher conversion rate than the direct biofilm-based approach,as it is tunable via cathode potential control and accelerates electrosynthesis from CO_(2).Here we report high acetate titers can be achieved via improved in situ H_(2)supply by nickel foam decorated carbon felt cathode in mixed community MES systems.Acetate concentration of 12.5 g L^(-1)was observed in 14 days with nickel-carbon cathode at a poised potential of-0.89 V(vs.standard hydrogen electrode,SHE),which was much higher than cathodes using stainless steel(5.2 g L^(-1))or carbon felt alone(1.7 g L^(-1))with the same projected surface area.A higher acetate concentration of 16.0 g L^(-1)in the cathode was achieved over long-term operation for 32 days,but crossover was observed in batch operation,as additional acetate(5.8 g L^(-1))was also found in the abiotic anode chamber.We observed the low Faradaic efficiencies in acetate production,attributed to partial H_(2)utilization for electrosynthesis.The selective acetate production with high titer demonstrated in this study shows the H_(2)-mediated electron transfer with common cathode materials carries good promise in MES development.
基金supported by grants from National Natural Science Foundation of China (32070097 and 91951202)National Key Research and Development Program of China (2019YFA0904800).
文摘The consumption of non-renewable fossil fuels has directly contributed to a dramatic rise in global carbon dioxide(CO_(2))emissions,posing an ongoing threat to the ecological security of the Earth.Microbial electrosynthesis(MES)is an innovative energy regeneration strategy that offers a gentle and efficient approach to converting CO_(2) into high-value products.The cathode chamber is a vital component of an MES system and its internal factors play crucial roles in improving the performance of the MES system.Therefore,this review aimed to provide a detailed analysis of the key factors related to the cathode chamber in the MES system.The topics covered include inward extracellular electron transfer pathways,cathode materials,applied cathode potentials,catholyte pH,and reactor configuration.In addition,this review analyzes and discusses the challenges and promising avenues for improving the conversion of CO_(2) into high-value products via MES.
基金supported by the Japan Society for the Promotion of Science (JSPS) through a Grant-in-Aid for Scientific Research (No. 17H01300)。
文摘Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide,which is a greenhouse gas,to produce methane which acts as an energy source,without using organic substances.However,this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic catalyst.When coupled with the oxidation of HS–to SO_(4)^(2-),methane production is thermodynamically more feasible,thus implying its production at a considerably lower applied voltage.In this study,we demonstrated the possibility of electrotrophic methane production coupled with HS–oxidation in a cost-effective bioanode chamber in the MES without organic substrates at a low applied voltage of 0.2 V.In addition,microbial community analyses of biomass enriched in the bioanode and biocathode were used to reveal the most probable pathway for methane production from HS–oxidation.In the bioanode,electroautotrophic SO_(4)^(2-)production accompanied with electron donation to the electrode is performed mainly by the following two steps:first,incomplete sulfide oxidation to sulfur cycle intermediates (SCI) is performed;then the produced SCI are disproportionated to HS^(–)and SO_(4)^(2-).In the biocathode,methane is produced mainly via H_(2)and acetate by electronaccepting syntrophic bacteria,homoacetogens,and acetoclastic archaea.Here,a new ecofriendly MES with biological H_(2)S removal is established.
基金supported by the Japan Society for the Promotion of Science(JSPS)as a Grant-in-Aid for Scientific Research(No.17H01300)。
文摘Methane is produced in a microbial electrosynthesis system(MES) without organic substrates. However, a relatively high applied voltage is required for the bioelectrical reactions.In this study, we demonstrated that electrotrophic methane production at the biocathode was achieved even at a very low voltage of 0.1 V in an MES, in which abiotic HS-oxidized to SO_(4)^(2-) at the anodic carbon-cloth surface coated with platinum powder. In addition, microbial community analysis revealed the most probable pathway for methane production from electrons. First, electrotrophic H_(2) was produced by syntrophic bacteria, such as Syntrophorhabdus, Syntrophobacter, Syntrophus, Leptolinea, and Aminicenantales, with the direct acceptance of electrons at the biocathode. Subsequently, most of the produced H_(2) was converted to acetate by homoacetogens, such as Clostridium and Spirochaeta 2. In conclusion,the majority of the methane was indirectly produced by a large population of acetoclastic methanogens, namely Methanosaeta, via acetate. Further, hydrogenotrophic methanogens,including Methanobacterium and Methanolinea, produced methane via H_(2).
