Adventitious root(AR)formation is critical for the efficient propagation of elite horticultural and forestry crops.Despite decades of research,the cellular processes and molecular mechanisms underlying AR induction in...Adventitious root(AR)formation is critical for the efficient propagation of elite horticultural and forestry crops.Despite decades of research,the cellular processes and molecular mechanisms underlying AR induction in woody plants remain obscure.We examined the details of AR formation in apple(Malus domestica)M.9 rootstock,the most widely used dwarf rootstock for intensive production,and investigated the role of polar auxin transport in postembryonic organogenesis.AR formation begins with a series of founder cell divisions and elongation of the interfascicular cambium adjacent to vascular tissues.This process is associated with a relatively high indole acetic acid(IAA)content and hydrolysis of starch grains.Exogenous auxin treatment promoted this cell division,as well as the proliferation and reorganization of the endoplasmic reticulum and Golgi membrane.In contrast,treatment with the auxin transport inhibitor N-1-naphthylphthalamic acid(NPA)inhibited cell division in the basal region of the cuttings and resulted in abnormal cell divisions during the early stage of AR formation.In addition,PIN-FORMED(PIN)transcripts were differentially expressed throughout the whole AR development process.We also detected upregulation of MdPIN8 and MdPIN10 during induction;upregulation of MdPIN4,MdPIN5,and MdPIN8 during extension;and upregulation of all MdPINs during AR initiation.This research provides an improved understanding of the cellular and molecular underpinnings of the AR process in woody plants.展开更多
Photocatalytic hydrogen evolution through water splitting holds tremendous promise for converting solar energy into a clean and renewable fuel source.However,the efficiency of photocatalysis is often hindered by poor ...Photocatalytic hydrogen evolution through water splitting holds tremendous promise for converting solar energy into a clean and renewable fuel source.However,the efficiency of photocatalysis is often hindered by poor light absorption,insufficient charge separation,and slow reaction kinetics of the photocatalysts.In this study,we designed and synthesized a novel S-scheme heterojunction comprising Ti_(3)C_(2)MXene,CdS nanorods,and nitrogen-doped carbon coated Cu_(2)O(Cu_(2)O@NC)core-shell nanoparticles.Ti_(3)C_(2)MXene as a cocatalyst enhances the light absorption and charge transfer of CdS nanorods.Simultaneously,the core-shell Cu_(2)O@NC nanoparticles establish a pathway for transferring photogenerated electrons and create a favorable band alignment for efficient hydrogen evolution.The synergistic effects of Ti_(3)C_(2)MXene and Cu_(2)O@NC on CdS nanorods result in multiple charge transfer channels and improved photocatalytic performance.The optimal hydrogen evolution rate of the Ti_(3)C_(2)-CdS-Cu_(2)O@NC S-scheme heterojunction photocatalyst is 7.4 times higher than that of pure CdS.Experimental techniques and DFT calculations were employed to explore the structure,morphology,optical properties,charge dynamics,and band structure of the heterojunction.The results revealed that the S-scheme mechanism effectively suppresses the recombination of photogenerated carriers and facilitates the separation and migration of photo-generated electrons and holes to the reaction sites.Furthermore,Ti_(3)C_(2)MXene provides abundant active sites essential for accelerating the surface H_(2)-evolution reaction kinetics.The Cu_(2)O@NC core-shell nanoparticles with a large surface area and high stability are closely adhered to CdS nanorods and establish an S-scheme internal electric field with CdS nanorods to drive charge separation.This investigation provides valuable insights into the rational design of CdS-based photocatalysts,enabling efficient hydrogen production by harnessing the robust kinetic driving force provided by the S-scheme heterojunctions.展开更多
Photocatalytic hydrogen evolution from water splitting is an appealing method for producing clean chemical fuels.Cu_(2)O,with a suitable bandgap,holds promise as a semiconductor for this process.However,the strong pho...Photocatalytic hydrogen evolution from water splitting is an appealing method for producing clean chemical fuels.Cu_(2)O,with a suitable bandgap,holds promise as a semiconductor for this process.However,the strong photo-corrosion and rapid charge recombination of Cu_(2)O strongly limit its application in the photocatalytic fields.Herein,an S-scheme heterojunction photocatalyst composed of TiO_(2)and Cu_(2)O was rationally designed to effectively avoid the photo-corrosion of Cu_(2)O.The introduction of an interfacial nitrogen-doped carbon(NC)layer switches the heterojunction interfacial charge transfer pathway from the p-n to S-scheme heterojunction,which avoids excessive accumulation of photogenerated holes on the surface of Cu_(2)O.Meanwhile,the hybrid structure shows a broad spectral response(300-800 nm)and efficient charge separation and transfer efficiency.Interestingly,the highest photocatalytic hydrogen evolution rate of TiO_(2)-NC-3%Cu_(2)O-3%Ni is 13521.9μmol g^(-1)h^(-1),which is approximately 664.1 times higher than that of pure Cu_(2)O.In-situ X-ray photoelectron spectroscopy and Kelvin probe confirm the charge transfer mechanism of S-scheme heterojunction.The formation of S-scheme heterojunctions effectively accelerates the separation of photogenerated electron-hole pairs and enhances redox capacity,thereby improving the photocatalytic performance and stability of Cu_(2)O.This study provides valuable insights into the rational design of highly efficient Cu_(2)O-based heterojunction photocatalysts for hydrogen production.展开更多
基金supported by the National Natural Science Foundation of China(Grant no.31601738).
文摘Adventitious root(AR)formation is critical for the efficient propagation of elite horticultural and forestry crops.Despite decades of research,the cellular processes and molecular mechanisms underlying AR induction in woody plants remain obscure.We examined the details of AR formation in apple(Malus domestica)M.9 rootstock,the most widely used dwarf rootstock for intensive production,and investigated the role of polar auxin transport in postembryonic organogenesis.AR formation begins with a series of founder cell divisions and elongation of the interfascicular cambium adjacent to vascular tissues.This process is associated with a relatively high indole acetic acid(IAA)content and hydrolysis of starch grains.Exogenous auxin treatment promoted this cell division,as well as the proliferation and reorganization of the endoplasmic reticulum and Golgi membrane.In contrast,treatment with the auxin transport inhibitor N-1-naphthylphthalamic acid(NPA)inhibited cell division in the basal region of the cuttings and resulted in abnormal cell divisions during the early stage of AR formation.In addition,PIN-FORMED(PIN)transcripts were differentially expressed throughout the whole AR development process.We also detected upregulation of MdPIN8 and MdPIN10 during induction;upregulation of MdPIN4,MdPIN5,and MdPIN8 during extension;and upregulation of all MdPINs during AR initiation.This research provides an improved understanding of the cellular and molecular underpinnings of the AR process in woody plants.
基金National Natural Science Foundation of China(21975084,51672089)Natural Science Foundation of Guangdong Province(2021A1515010075)for their support
文摘Photocatalytic hydrogen evolution through water splitting holds tremendous promise for converting solar energy into a clean and renewable fuel source.However,the efficiency of photocatalysis is often hindered by poor light absorption,insufficient charge separation,and slow reaction kinetics of the photocatalysts.In this study,we designed and synthesized a novel S-scheme heterojunction comprising Ti_(3)C_(2)MXene,CdS nanorods,and nitrogen-doped carbon coated Cu_(2)O(Cu_(2)O@NC)core-shell nanoparticles.Ti_(3)C_(2)MXene as a cocatalyst enhances the light absorption and charge transfer of CdS nanorods.Simultaneously,the core-shell Cu_(2)O@NC nanoparticles establish a pathway for transferring photogenerated electrons and create a favorable band alignment for efficient hydrogen evolution.The synergistic effects of Ti_(3)C_(2)MXene and Cu_(2)O@NC on CdS nanorods result in multiple charge transfer channels and improved photocatalytic performance.The optimal hydrogen evolution rate of the Ti_(3)C_(2)-CdS-Cu_(2)O@NC S-scheme heterojunction photocatalyst is 7.4 times higher than that of pure CdS.Experimental techniques and DFT calculations were employed to explore the structure,morphology,optical properties,charge dynamics,and band structure of the heterojunction.The results revealed that the S-scheme mechanism effectively suppresses the recombination of photogenerated carriers and facilitates the separation and migration of photo-generated electrons and holes to the reaction sites.Furthermore,Ti_(3)C_(2)MXene provides abundant active sites essential for accelerating the surface H_(2)-evolution reaction kinetics.The Cu_(2)O@NC core-shell nanoparticles with a large surface area and high stability are closely adhered to CdS nanorods and establish an S-scheme internal electric field with CdS nanorods to drive charge separation.This investigation provides valuable insights into the rational design of CdS-based photocatalysts,enabling efficient hydrogen production by harnessing the robust kinetic driving force provided by the S-scheme heterojunctions.
基金X.Li thanks the National Natural Science Foundation of China(Nos.21975084 and 51672089)the Natural Science Foundation of Guangdong Province(No.2021A1515010075)for their support.X.Peng thanks the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No.PCRRF21028)for the support.
文摘Photocatalytic hydrogen evolution from water splitting is an appealing method for producing clean chemical fuels.Cu_(2)O,with a suitable bandgap,holds promise as a semiconductor for this process.However,the strong photo-corrosion and rapid charge recombination of Cu_(2)O strongly limit its application in the photocatalytic fields.Herein,an S-scheme heterojunction photocatalyst composed of TiO_(2)and Cu_(2)O was rationally designed to effectively avoid the photo-corrosion of Cu_(2)O.The introduction of an interfacial nitrogen-doped carbon(NC)layer switches the heterojunction interfacial charge transfer pathway from the p-n to S-scheme heterojunction,which avoids excessive accumulation of photogenerated holes on the surface of Cu_(2)O.Meanwhile,the hybrid structure shows a broad spectral response(300-800 nm)and efficient charge separation and transfer efficiency.Interestingly,the highest photocatalytic hydrogen evolution rate of TiO_(2)-NC-3%Cu_(2)O-3%Ni is 13521.9μmol g^(-1)h^(-1),which is approximately 664.1 times higher than that of pure Cu_(2)O.In-situ X-ray photoelectron spectroscopy and Kelvin probe confirm the charge transfer mechanism of S-scheme heterojunction.The formation of S-scheme heterojunctions effectively accelerates the separation of photogenerated electron-hole pairs and enhances redox capacity,thereby improving the photocatalytic performance and stability of Cu_(2)O.This study provides valuable insights into the rational design of highly efficient Cu_(2)O-based heterojunction photocatalysts for hydrogen production.
