The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)signific...The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)significantly enriches photogenerated electrons at Ni active sites and enhances the performance for CO_(2) reduction into syngas.During photocatalytic CO_(2) reduction,Ni single‐atom‐anchored P‐modulated carbon nitride showed an impressive syngas yield rate of 85μmol gcat^(−1)h^(−1) and continuously adjustable CO/H_(2) ratios ranging from 5:1 to 1:2,which exceeded those of most of the reported carbon nitride‐based single‐atom catalysts.Mechanistic studies reveal that P doping improves the conductivity of catalysts,which promotes photogenerated electron transfer to the Ni active sites rather than dissipate randomly at low‐activity nonmetallic sites,facilitating the CO_(2)‐to‐syngas photoreduction process.展开更多
Photocatalytic carbon dioxide(CO_(2))to carbon monoxide(CO)offers a promising way for both alleviating the greenhouse effect and meeting the industrial demand.Herein,we constructed a Co single-atom catalyst with inten...Photocatalytic carbon dioxide(CO_(2))to carbon monoxide(CO)offers a promising way for both alleviating the greenhouse effect and meeting the industrial demand.Herein,we constructed a Co single-atom catalyst with intentional low-coordination environment design on porous ZnO(denoted as Co1/ZnO).Impressively,Co1/ZnO exhibited a remarkable activity with a CO yield rate of 22.25 mmol·g^(-1)·h^(-1) and a selectivity of 80.2%for CO_(2) photoreduction reactions under visible light.The incorporation of single Co atoms provided an additional photo-generated electron transfer channel,which suppressed the carrier recombination of photocatalysts.Moreover,the unsaturated Co active sites were capable to adsorb CO_(2) molecule spontaneously,thus facilitating the activation of CO_(2) molecule during CO_(2) reduction course.展开更多
Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal s...Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling performance.As an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported photocatalysts.By virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion.展开更多
CO_(2)photoreduction to high-valued CH_(4)is highly attractive,whereas the CH_(4)selectivity and activity,especially under atmospheric CO_(2),is still unsatisfying.Here,we design spatially-separated redox sites on two...CO_(2)photoreduction to high-valued CH_(4)is highly attractive,whereas the CH_(4)selectivity and activity,especially under atmospheric CO_(2),is still unsatisfying.Here,we design spatially-separated redox sites on two-dimensional heterostructured nanosheets with loaded metal oxides,thus achieving high reactivity and selectivity of photocatalytic atmospheric CO_(2)reduction to CH_(4).Taking the synthetic In_(2)O_(3)/In_(2)S_(3)nanosheets with loaded PdO quantum dots as a prototype,quasi in-situ X-ray photoelectron spectra reveal the Pd sites accumulate photogenerated holes for dissociating H_(2)O and the In sites accept photoexcited electrons to activate CO_(2).Moreover,the Pd-OD bond is confirmed by in-situ Fourier-transform infrared spectra during the D2O labeling experiment,indicating the PdO quantum dots participate in H_(2)O oxidation to supply hydrogen species for CO_(2)methanation.As a result,in a simulated air atmosphere,the PdO-In_(2)O_(3)/In_(2)S_(3)nanosheets enable favorable atmospheric CO_(2)-to CH_(4)photoreduction with nearly 100%selectivity and ultralong stability of 240 h as well as CO_(2)conversion of 48.2%.This study opens an approach towards designing photocatalysts with spatially-separated redox sites to achieve efficient oxidation and reduction of CO_(2)photocatalysis to CH_(4).展开更多
Various aspects of the organisms adapt to cyclically changing environmental conditions via transcriptional regulation.However,the role of rhythmicity in altering the global aspects of metabolism is poorly characterize...Various aspects of the organisms adapt to cyclically changing environmental conditions via transcriptional regulation.However,the role of rhythmicity in altering the global aspects of metabolism is poorly characterized.Here,we subjected four rice(Oryza sativa)varieties to a range of metabolic profiles and RNA-seq to investigate the temporal relationships of rhythm between transcription and metabolism.More than 40%of the rhythmic genes and a quarter of metabolites conservatively oscillated across four rice accessions.Compared with the metabolome,the transcriptome was more strongly regulated by rhythm;however,the rhythm of metabolites had an obvious opposite trend between day and night.Through association analysis,the time delay of rhythmic transmission from the transcript to the metabolite level was~4 h under long-day conditions,although the transmission was nearly synchronous for carbohydrate and nucleotide metabolism.The rhythmic accumulation of metabolites maintained highly coordinated temporal relationships in the metabolic network,whereas the correlation of some rhythmic metabolites,such as branched-chain amino acids(BCAAs),was significantly different intervariety.We further demonstrated that the cumulative diversity of BCAAs was due to the differential expression of branched-chain aminotransferase 2 at dawn.Our research reveals the flexible pattern of rice metabolic rhythm existing with conservation and diversity.展开更多
High-rate CO_(2)-to-CH_(4)photoreduction with high selectivity is highly attractive,which is a win-win strategy for mitigating the greenhouse effect and the energy crisis.However,the poor photocatalytic activity and l...High-rate CO_(2)-to-CH_(4)photoreduction with high selectivity is highly attractive,which is a win-win strategy for mitigating the greenhouse effect and the energy crisis.However,the poor photocatalytic activity and low product selectivity hinder the practical application.To precisely tailor the product selectivity and realize high-rate CO_(2)photoreduction,we design atomically precise Pd species supported on In_(2)O_(3)nanosheets.Taking the synthetic 1.30Pd/In_(2)O_(3)nanosheets as an example,the aberration-correction high-angle annular dark-field scanning transmission electron microscopy image displayed the Pd species atomically dispersed on the In_(2)O_(3)nanosheets.Raman spectra and X-ray photoelectron spectra established that the strong interaction between the Pd species and the In_(2)O_(3)substrate drove electron transfer from In to Pd species,resulting in electron-enriched Pd sites for CO_(2)activation.Synchrotronradiation photoemission spectroscopy demonstrated that the Pd species can tailor the conduction band edge of In_(2)O_(3)nanosheets to match the CO_(2)-to-CH_(4)pathway,instead of the CO_(2)-to-CO pathway,which theoretically accounts for the high CH_(4)selectivity.Moreover,in situ X-ray photoelectron spectroscopy unveiled that the catalytically active sites had a change from In species to Pd species over the 1.30Pd/In_(2)O_(3)nanosheets.In situ FTIR and EPR spectra reveal the atomically precise Pd species with rich electrons prefer to adsorb the electrophilic protons for accelerating the*COOH intermediates hydrogenation into CH_(4).Consequently,the 1.30Pd/In_(2)O_(3)nanosheets reached CO_(2)-to-CH_(4)photoconversion with 100%selectivity and 81.2μmol g^(−1)h^(−1)productivity.展开更多
基金Fundamental Research Funds for the Central Universities,Grant/Award Number:WK2060000016National Natural Science Foundation of China,Grant/Award Numbers:12222508,U1932213+2 种基金Youth Innovation Promotion Association of the Chinese Academy of Sciences,Grant/Award Number:2020454USTC Research Funds of the Double First‐Class Initiative,Grant/Award Number:YD2310002005National Key R&D Program of China,Grant/Award Number:2023YFA1506304。
文摘The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)significantly enriches photogenerated electrons at Ni active sites and enhances the performance for CO_(2) reduction into syngas.During photocatalytic CO_(2) reduction,Ni single‐atom‐anchored P‐modulated carbon nitride showed an impressive syngas yield rate of 85μmol gcat^(−1)h^(−1) and continuously adjustable CO/H_(2) ratios ranging from 5:1 to 1:2,which exceeded those of most of the reported carbon nitride‐based single‐atom catalysts.Mechanistic studies reveal that P doping improves the conductivity of catalysts,which promotes photogenerated electron transfer to the Ni active sites rather than dissipate randomly at low‐activity nonmetallic sites,facilitating the CO_(2)‐to‐syngas photoreduction process.
基金supported by the National Natural Science Foundation of China(Nos.1222508,U1932213)the Fundamental Research Funds for the Central Universities(No.WK2060000016)+1 种基金the USTC Research Funds of the Double First-Class Initiative(No.YD2310002005)the Youth Innovation Promotion Association CAS(No.2020454)。
文摘Photocatalytic carbon dioxide(CO_(2))to carbon monoxide(CO)offers a promising way for both alleviating the greenhouse effect and meeting the industrial demand.Herein,we constructed a Co single-atom catalyst with intentional low-coordination environment design on porous ZnO(denoted as Co1/ZnO).Impressively,Co1/ZnO exhibited a remarkable activity with a CO yield rate of 22.25 mmol·g^(-1)·h^(-1) and a selectivity of 80.2%for CO_(2) photoreduction reactions under visible light.The incorporation of single Co atoms provided an additional photo-generated electron transfer channel,which suppressed the carrier recombination of photocatalysts.Moreover,the unsaturated Co active sites were capable to adsorb CO_(2) molecule spontaneously,thus facilitating the activation of CO_(2) molecule during CO_(2) reduction course.
基金supported by the National Key R&D Program of China(2019YFA0210004,2022YFA1502904,2021YFA1501502)the National Natural Science Foundation of China(22125503,21975242,U2032212,21890754,22002148)+1 种基金2023 Synchrotron Radiation Joint Fund of USTCthe Youth Innovation Promotion Association of CAS(CX2340007003)。
文摘Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling performance.As an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported photocatalysts.By virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion.
基金supported by the National Key Research and Development Program of China(2021YFA1500402)the Strategic Priority Research Program of the Chinese Academy of Sciences(CAS)(XDB0450302)+3 种基金the National Natural Science Foundation of China(22161142001,U22A20401,and 22101269)International Partnership Program of CAS(123GJHZ2022028MI)the Fundamental Research Funds for the Central Universities(WK3450000007 and WK2060000038)the XAS supports from Beijing Synchrotron Radiation Facility(BSRF)。
基金supported by the National Key Research and Development Program of China(2022YFA1502904,2019YFA0210004,2021YFA1501502)the National Natural Science Foundation of China(22125503,21975242,U2032212,21890754,22002148)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB36000000)the Youth Innovation Promotion Association of Chinese Academy of Sciences(CX2340007003)the University Synergy Innovation Program of Anhui Province(GXXT-2020-001)
文摘CO_(2)photoreduction to high-valued CH_(4)is highly attractive,whereas the CH_(4)selectivity and activity,especially under atmospheric CO_(2),is still unsatisfying.Here,we design spatially-separated redox sites on two-dimensional heterostructured nanosheets with loaded metal oxides,thus achieving high reactivity and selectivity of photocatalytic atmospheric CO_(2)reduction to CH_(4).Taking the synthetic In_(2)O_(3)/In_(2)S_(3)nanosheets with loaded PdO quantum dots as a prototype,quasi in-situ X-ray photoelectron spectra reveal the Pd sites accumulate photogenerated holes for dissociating H_(2)O and the In sites accept photoexcited electrons to activate CO_(2).Moreover,the Pd-OD bond is confirmed by in-situ Fourier-transform infrared spectra during the D2O labeling experiment,indicating the PdO quantum dots participate in H_(2)O oxidation to supply hydrogen species for CO_(2)methanation.As a result,in a simulated air atmosphere,the PdO-In_(2)O_(3)/In_(2)S_(3)nanosheets enable favorable atmospheric CO_(2)-to CH_(4)photoreduction with nearly 100%selectivity and ultralong stability of 240 h as well as CO_(2)conversion of 48.2%.This study opens an approach towards designing photocatalysts with spatially-separated redox sites to achieve efficient oxidation and reduction of CO_(2)photocatalysis to CH_(4).
基金This work was supported by the Hainan Major Science and Technology Project(ZDKJ202002)the State Key Program of National Natural Science Foundation of China(31530052)+2 种基金the Key Research and Development Program of Hainan(ZDYF2020066)the Hainan Academician Innovation Platform(HD-YSZX-202003 and HD-YSZX-202004)the Hainan University Startup Fund(KYQD(ZR)1866).
文摘Various aspects of the organisms adapt to cyclically changing environmental conditions via transcriptional regulation.However,the role of rhythmicity in altering the global aspects of metabolism is poorly characterized.Here,we subjected four rice(Oryza sativa)varieties to a range of metabolic profiles and RNA-seq to investigate the temporal relationships of rhythm between transcription and metabolism.More than 40%of the rhythmic genes and a quarter of metabolites conservatively oscillated across four rice accessions.Compared with the metabolome,the transcriptome was more strongly regulated by rhythm;however,the rhythm of metabolites had an obvious opposite trend between day and night.Through association analysis,the time delay of rhythmic transmission from the transcript to the metabolite level was~4 h under long-day conditions,although the transmission was nearly synchronous for carbohydrate and nucleotide metabolism.The rhythmic accumulation of metabolites maintained highly coordinated temporal relationships in the metabolic network,whereas the correlation of some rhythmic metabolites,such as branched-chain amino acids(BCAAs),was significantly different intervariety.We further demonstrated that the cumulative diversity of BCAAs was due to the differential expression of branched-chain aminotransferase 2 at dawn.Our research reveals the flexible pattern of rice metabolic rhythm existing with conservation and diversity.
基金the National Key R&D Program of China(2022YFA1502904,2019YFA0210004,2021YFA1501502)National Natural Science Foundation of China(22125503,21975242,U2032212,21890754)+1 种基金Youth Innovation Promotion Association of CAS(CX2340007003)Technical Talent Promotion Plan(TS2021002).
文摘High-rate CO_(2)-to-CH_(4)photoreduction with high selectivity is highly attractive,which is a win-win strategy for mitigating the greenhouse effect and the energy crisis.However,the poor photocatalytic activity and low product selectivity hinder the practical application.To precisely tailor the product selectivity and realize high-rate CO_(2)photoreduction,we design atomically precise Pd species supported on In_(2)O_(3)nanosheets.Taking the synthetic 1.30Pd/In_(2)O_(3)nanosheets as an example,the aberration-correction high-angle annular dark-field scanning transmission electron microscopy image displayed the Pd species atomically dispersed on the In_(2)O_(3)nanosheets.Raman spectra and X-ray photoelectron spectra established that the strong interaction between the Pd species and the In_(2)O_(3)substrate drove electron transfer from In to Pd species,resulting in electron-enriched Pd sites for CO_(2)activation.Synchrotronradiation photoemission spectroscopy demonstrated that the Pd species can tailor the conduction band edge of In_(2)O_(3)nanosheets to match the CO_(2)-to-CH_(4)pathway,instead of the CO_(2)-to-CO pathway,which theoretically accounts for the high CH_(4)selectivity.Moreover,in situ X-ray photoelectron spectroscopy unveiled that the catalytically active sites had a change from In species to Pd species over the 1.30Pd/In_(2)O_(3)nanosheets.In situ FTIR and EPR spectra reveal the atomically precise Pd species with rich electrons prefer to adsorb the electrophilic protons for accelerating the*COOH intermediates hydrogenation into CH_(4).Consequently,the 1.30Pd/In_(2)O_(3)nanosheets reached CO_(2)-to-CH_(4)photoconversion with 100%selectivity and 81.2μmol g^(−1)h^(−1)productivity.
