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- 实验方案
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Interfacial Lattice‐Strain‐Driven Generation of Oxygen Vacancies in an Aerobic‐Annealed TiO <sub/>2</sub> (B) Electrode
摘要： Oxygen vacancies play crucial roles in defining physical and chemical properties of materials to enhance the performances in electronics, solar cells, catalysis, sensors, and energy conversion and storage. Conventional approaches to incorporate oxygen defects mainly rely on reducing the oxygen partial pressure for the removal of product to change the equilibrium position. However, directly affecting reactants to shift the reaction toward generating oxygen vacancies is lacking and to fill this blank in synthetic methodology is very challenging. Here, a strategy is demonstrated to create oxygen vacancies through making the reaction energetically more favorable via applying interfacial strain on reactants by coating, using TiO2(B) as a model system. Geometrical phase analysis and density functional theory simulations verify that the formation energy of oxygen vacancies is largely decreased under external strain. Benefiting from these, the obtained oxygen-deficient TiO2(B) exhibits impressively high level of capacitive charge storage, e.g., ≈53% at 0.5 mV s?1, far surpassing the ≈31% of the unmodified counterpart. Meanwhile, the modified electrode shows significantly enhanced rate capability delivering a capacity of 112 mAh g?1 at 20 C (≈6.7 A g?1), ≈30% higher than air-annealed TiO2 and comparable to vacuum-calcined TiO2. This work heralds a new paradigm of mechanical manipulation of materials through interfacial control for rational defect engineering.
关键词： aerobic-annealing,oxygen vacancy,pseudocapacitive charge storage,lithium-ion batteries,interfacial lattice strain
更新于2025-09-12 10:27:22
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Bifunctional nanoscale assemblies: multistate electrochromics coupled with charge trapping and release
摘要： We demonstrate controlled charge trapping and release, accompanied by multiple color changes in a metallo-organic bilayer. The dual functionality of the metallo-organic materials provides a fundamental insight into the metal-mediated electron transport pathways. The electrochemical processes are accompanied by distinct, four color–to–color transitions: red, transparent, orange, and brown. The bilayer consists of two elements: (i) a nanoscale gate consisting of a layer of well-defined polypyridyl ruthenium complexes bound to a flexible transparent electrode, and (ii) a charge storage layer consisting of isostructural iron complexes attached to the surface of the gate. This gate mediates or blocks electron transport in response to a voltage. The charge storage and release depend on the oxidation state of the layer of ruthenium complexes (= gate). Combining electrochemistry with optical data revealed mechanistic information: the brown coloration of the bilayer directly relates to the formation of intermediate ruthenium species, providing evidence for catalytic positive charge release mediated through the gate.
关键词： Thin films,Charge storage,Electrochromism,Metallo-organics,Electrochemistry
更新于2025-09-12 10:27:22
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Bifunctional nanoscale assemblies: multistate electrochromics coupled with charge trapping and release
摘要： We demonstrate controlled charge trapping and release, accompanied by multiple color changes in a metallo-organic bilayer. The dual functionality of the metallo-organic materials provides a fundamental insight into the metal-mediated electron transport pathways. The electrochemical processes are accompanied by distinct, four color–to–color transitions: red, transparent, orange, and brown. The bilayer consists of two elements: (i) a nanoscale gate consisting of a layer of well-defined polypyridyl ruthenium complexes bound to a flexible transparent electrode, and (ii) a charge storage layer consisting of isostructural iron complexes attached to the surface of the gate. This gate mediates or blocks electron transport in response to a voltage. The charge storage and release depend on the oxidation state of the layer of ruthenium complexes (= gate). Combining electrochemistry with optical data revealed mechanistic information: the brown coloration of the bilayer directly relates to the formation of intermediate ruthenium species, providing evidence for catalytic positive charge release mediated through the gate.
关键词： Thin films,Electrochromism,Metallo-organics,Electrochemistry,Charge storage
更新于2025-09-11 14:15:04