In this contribution,inspired by the excellent resource management and material transport function of leaf veins,the electrical transport function of metallized leaf veins is mimicked from the material transport funct...In this contribution,inspired by the excellent resource management and material transport function of leaf veins,the electrical transport function of metallized leaf veins is mimicked from the material transport function of the vein networks.By electroless copper plating on real leaf vein networks with copper thickness of only several hundred nanometre up to several micrometre,certain leaf veins can be converted to transparent conductive electrodes with an ultralow sheet resistance 100 times lower than that of state-of-the-art indium tin oxide thin films,combined with a broadband optical transmission of above 80%in the UV–VIS–IR range.Additionally,the resource efficiency of the vein-like electrode is characterized by the small amount of material needed to build up the networks and the low copper consumption during metallization.In particular,the high current density transport capability of the electrode of>6000 A cm^−2 was demonstrated.These superior properties of the vein-like structures inspire the design of high-performance transparent conductive electrodes without using critical materials and may significantly reduce the Ag consumption down to<10%of the current level for mass production of solar cells and will contribute greatly to the electrode for high power density concentrator solar cells,high power density Li-ion batteries,and supercapacitors.展开更多
Plant vascular cells are joined end to end along uninterrupted lines to connect shoot organs with roots;vascular strands are thus polar, continuous, and internally aligned. What controls the formation of vascular stra...Plant vascular cells are joined end to end along uninterrupted lines to connect shoot organs with roots;vascular strands are thus polar, continuous, and internally aligned. What controls the formation of vascular strands with these properties？ The “auxin canalization hypothesis”-based on positive feedback between auxin flow through a cell and the cell’s capacity for auxin transport-predicts the selection of continuous files of cells that transport auxin polarly, thus accounting for the polarity and continuity of vascular strands. By contrast, polar, continuous auxin transport-though required-is insufficient to promote internal alignment of vascular strands, implicating additional factors. The auxin canalization hypothesis was derived from the response of mature tissue to auxin application but is consistent with molecular and cellular events in embryo axis formation and shoot organ development. Objections to the hypothesis have been raised based on vascular organizations in callus tissue and shoot organs but seem unsupported by available evidence. Other objections call instead for further research; yet the inductive and orienting influence of auxin on continuous vascular differentiation remains unique.展开更多
基金the financial support from the BMWi within the projects TherSiTex(ZF4006804PR5)TexCool(ZF4006814BA8)
文摘In this contribution,inspired by the excellent resource management and material transport function of leaf veins,the electrical transport function of metallized leaf veins is mimicked from the material transport function of the vein networks.By electroless copper plating on real leaf vein networks with copper thickness of only several hundred nanometre up to several micrometre,certain leaf veins can be converted to transparent conductive electrodes with an ultralow sheet resistance 100 times lower than that of state-of-the-art indium tin oxide thin films,combined with a broadband optical transmission of above 80%in the UV–VIS–IR range.Additionally,the resource efficiency of the vein-like electrode is characterized by the small amount of material needed to build up the networks and the low copper consumption during metallization.In particular,the high current density transport capability of the electrode of>6000 A cm^−2 was demonstrated.These superior properties of the vein-like structures inspire the design of high-performance transparent conductive electrodes without using critical materials and may significantly reduce the Ag consumption down to<10%of the current level for mass production of solar cells and will contribute greatly to the electrode for high power density concentrator solar cells,high power density Li-ion batteries,and supercapacitors.
基金supported by Discovery Grants of the Natural Sciences and Engineering Research Council of Canada (NSERC)M.G.S. was supported by an NSERC CGS‐M Scholarship and an NSERC CGS‐D Scholarship
文摘Plant vascular cells are joined end to end along uninterrupted lines to connect shoot organs with roots;vascular strands are thus polar, continuous, and internally aligned. What controls the formation of vascular strands with these properties？ The “auxin canalization hypothesis”-based on positive feedback between auxin flow through a cell and the cell’s capacity for auxin transport-predicts the selection of continuous files of cells that transport auxin polarly, thus accounting for the polarity and continuity of vascular strands. By contrast, polar, continuous auxin transport-though required-is insufficient to promote internal alignment of vascular strands, implicating additional factors. The auxin canalization hypothesis was derived from the response of mature tissue to auxin application but is consistent with molecular and cellular events in embryo axis formation and shoot organ development. Objections to the hypothesis have been raised based on vascular organizations in callus tissue and shoot organs but seem unsupported by available evidence. Other objections call instead for further research; yet the inductive and orienting influence of auxin on continuous vascular differentiation remains unique.
