Highly crystalline carbon nitride polymers have shown great opportunities in overall water photosplitting;however,their mission in light-driven CO_(2)conversion remains to be explored.In this work,crystalline carbon n...Highly crystalline carbon nitride polymers have shown great opportunities in overall water photosplitting;however,their mission in light-driven CO_(2)conversion remains to be explored.In this work,crystalline carbon nitride(CCN)nanosheets of poly triazine imide(PTI)embedded with melon domains are fabricated by KCl/LiCl-mediated polycondensation of dicyandiamide,the surface of which is subsequently deposited with ultrafine WO_(3)nanoparticles to construct the CCN/WO_(3)heterostructure with a S-scheme interface.Systematic characterizations have been conducted to reveal the compositions and structures of the S-scheme CCN/WO_(3)hybrid,featuring strengthened optical capture,enhanced CO_(2)adsorption and activation,attractive textural properties,as well as spatial separation and directed movement of light-triggered charge carriers.Under mild conditions,the CCN/WO_(3)catalyst with optimized composition displays a high photocatalytic activity for reducing CO_(2)to CO in a rate of 23.0μmol/hr(i.e.,2300μmol/(hr·g)),which is about 7-fold that of pristine CCN,along with a high CO selectivity of 90.6%against H2formation.Moreover,it also manifests high stability and fine reusability for the CO_(2)conversion reaction.The CO_(2)adsorption and conversion processes on the catalyst are monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS),identifying the crucial intermediates of CO_(2)^(*)-,COOH^(*)and CO^(*),which integrated with the results of performance evaluation proposes the possible CO_(2)reduction mechanism.展开更多
Histone acetyltransferase(HAT)catalyzes histone acetylation and is involved in plant growth and development and stress responses.Here,37 CitHAT genes were identifed in Citrus clementina.Their physicochemical propertie...Histone acetyltransferase(HAT)catalyzes histone acetylation and is involved in plant growth and development and stress responses.Here,37 CitHAT genes were identifed in Citrus clementina.Their physicochemical properties,chromosomal location,gene structure,conserved domain and motif,and cis-acting elements were characterized.CitHATs were classifed into four subfamilies based on protein sequence homology,which was strongly supported by gene structure,conserved domain,and motif analysis.The cis-acting elements in gene promoter regions were predicted to be associated with the regulation of plant growth,stress resistance,and response to hormones.Phenotypic and transcriptomic analyses of citrus callus with mock treatment and HAT inhibitor treatment revealed that increased citric acid content in inhibitor treatment may be attributed to differential expression of CitPEPCK2 and CitGS2,which may be due to the hypo-acetylation of histone H3.The expression patterns of CitHATs in citrus fruit development stages showed that CitHAG11 and CitHAG28 exhibited a negative correlation with citric acid content.Our study associates the potential function of histone acetyltransferases in citrate metabolism and extends the molecular mechanism of citrate metabolism in fruits.展开更多
Sunlight-induced photocatalytic carbon dioxide(CO_(2))reduction to energy-rich chemicals by metal-free polymeric carbon nitride(CN)semiconductor is a promising tactic for sustained solar fuel production.However,the re...Sunlight-induced photocatalytic carbon dioxide(CO_(2))reduction to energy-rich chemicals by metal-free polymeric carbon nitride(CN)semiconductor is a promising tactic for sustained solar fuel production.However,the reaction efficiency of CO_(2)photoreduction is restrained seriously by the rapid recombination of photogenerated carriers on CN polymer.Herein,we incorporate 2-aminopyridine molecule with strong electron-withdrawing group into the skeleton edge of CN layers through a facile one-pot thermal polymerization strategy using urea as the precursor,which renders a modified carbon nitride(ACN)with extended optical harvesting,abundant nitrogen defects and ultrathin nanosheet structure.Consequently,the ACN photocatalyst with desirable structural features attains enhanced separation and migration of photoexcited charge carriers.Under visible light irradiation with Co(bpy)^(2+)_(3)as a cocatalyst,the optimized ACN sample manifests a high CO_(2)deoxygnative reduction activity and high sta-bility,providing a CO yielding rate of 17μmol h^(-1),which is significantly higher than that of pristine CN.The key intermediates engaged in CO_(2)photoreduction reaction are determined by the in situ diffuse reflectance infrared Fourier transform spectroscopy,which sponsors the construction of the possible photocatalytic CO_(2)reduction mechanism on ACN nanosheets.展开更多
基金supported by the National Key R&D Program of China(Nos.2021YFA1502100 and 2022YFE0114800)the National Natural Science Foundation of China(Nos.22311540011 and 21973014)。
文摘Highly crystalline carbon nitride polymers have shown great opportunities in overall water photosplitting;however,their mission in light-driven CO_(2)conversion remains to be explored.In this work,crystalline carbon nitride(CCN)nanosheets of poly triazine imide(PTI)embedded with melon domains are fabricated by KCl/LiCl-mediated polycondensation of dicyandiamide,the surface of which is subsequently deposited with ultrafine WO_(3)nanoparticles to construct the CCN/WO_(3)heterostructure with a S-scheme interface.Systematic characterizations have been conducted to reveal the compositions and structures of the S-scheme CCN/WO_(3)hybrid,featuring strengthened optical capture,enhanced CO_(2)adsorption and activation,attractive textural properties,as well as spatial separation and directed movement of light-triggered charge carriers.Under mild conditions,the CCN/WO_(3)catalyst with optimized composition displays a high photocatalytic activity for reducing CO_(2)to CO in a rate of 23.0μmol/hr(i.e.,2300μmol/(hr·g)),which is about 7-fold that of pristine CCN,along with a high CO selectivity of 90.6%against H2formation.Moreover,it also manifests high stability and fine reusability for the CO_(2)conversion reaction.The CO_(2)adsorption and conversion processes on the catalyst are monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS),identifying the crucial intermediates of CO_(2)^(*)-,COOH^(*)and CO^(*),which integrated with the results of performance evaluation proposes the possible CO_(2)reduction mechanism.
基金the National Key Research and Development Program of China(No.2022YFD2100102)the Fundamental Research Funds for the Central Universities(No.226-2023-00152)+1 种基金the 111 Project(No.B17039)Zhejiang Provincial Cooperative Extension Project of Agricultural Key Technology(No.2022XTTGGP01),China.
文摘Histone acetyltransferase(HAT)catalyzes histone acetylation and is involved in plant growth and development and stress responses.Here,37 CitHAT genes were identifed in Citrus clementina.Their physicochemical properties,chromosomal location,gene structure,conserved domain and motif,and cis-acting elements were characterized.CitHATs were classifed into four subfamilies based on protein sequence homology,which was strongly supported by gene structure,conserved domain,and motif analysis.The cis-acting elements in gene promoter regions were predicted to be associated with the regulation of plant growth,stress resistance,and response to hormones.Phenotypic and transcriptomic analyses of citrus callus with mock treatment and HAT inhibitor treatment revealed that increased citric acid content in inhibitor treatment may be attributed to differential expression of CitPEPCK2 and CitGS2,which may be due to the hypo-acetylation of histone H3.The expression patterns of CitHATs in citrus fruit development stages showed that CitHAG11 and CitHAG28 exhibited a negative correlation with citric acid content.Our study associates the potential function of histone acetyltransferases in citrate metabolism and extends the molecular mechanism of citrate metabolism in fruits.
基金supported by the National Key R&D Program of China(2021YFA1502100 and 2022YFE0114800)the National Natural Science Foundation of China(22372035,22302039 and 22311540011).
文摘Sunlight-induced photocatalytic carbon dioxide(CO_(2))reduction to energy-rich chemicals by metal-free polymeric carbon nitride(CN)semiconductor is a promising tactic for sustained solar fuel production.However,the reaction efficiency of CO_(2)photoreduction is restrained seriously by the rapid recombination of photogenerated carriers on CN polymer.Herein,we incorporate 2-aminopyridine molecule with strong electron-withdrawing group into the skeleton edge of CN layers through a facile one-pot thermal polymerization strategy using urea as the precursor,which renders a modified carbon nitride(ACN)with extended optical harvesting,abundant nitrogen defects and ultrathin nanosheet structure.Consequently,the ACN photocatalyst with desirable structural features attains enhanced separation and migration of photoexcited charge carriers.Under visible light irradiation with Co(bpy)^(2+)_(3)as a cocatalyst,the optimized ACN sample manifests a high CO_(2)deoxygnative reduction activity and high sta-bility,providing a CO yielding rate of 17μmol h^(-1),which is significantly higher than that of pristine CN.The key intermediates engaged in CO_(2)photoreduction reaction are determined by the in situ diffuse reflectance infrared Fourier transform spectroscopy,which sponsors the construction of the possible photocatalytic CO_(2)reduction mechanism on ACN nanosheets.
