Unstable electrode/electrolyte interfaces and heterogeneous Zn deposition would reduce the Coulombic efficiency and cycle life of Zn metal batteries(ZMBs). Applying water-in-salt(WIS) electrolytes has proven to be an ...Unstable electrode/electrolyte interfaces and heterogeneous Zn deposition would reduce the Coulombic efficiency and cycle life of Zn metal batteries(ZMBs). Applying water-in-salt(WIS) electrolytes has proven to be an effective strategy to address the above issues. However, an understanding of the reaction mechanisms on the Zn anode at nanoscale is still elusive. Here we utilize in situ atomic force microscopy to visualize the solid electrolyte interphase(SEI) formation and Zn deposition/dissolution processes in WIS electrolyte and construct relationships between interfacial behavior and electrochemical performance. The formation processes, chemical properties, and structure of the on-site formed SEI are deeply explored.The SEI with a “plum-pudding” model can guide uniform Zn deposition and reversible dissolution. Mechanistic understanding of the interfacial evolution of the SEI layer and Zn deposition/dissolution has been achieved and will benefit the structural optimization and interfacial engineering of ZMBs.展开更多
Zn metal batteries are highly attractive because of their high theoretical specific capacity,intrinsic safety and resource availability.However,further development is significantly hindered by low Coulomb efficiency,w...Zn metal batteries are highly attractive because of their high theoretical specific capacity,intrinsic safety and resource availability.However,further development is significantly hindered by low Coulomb efficiency,which is closely linked to reaction processes occurring at electrode/electrolyte interfaces.Herein,we have achieved a real-time visualization and comprehensive analysis of the interfacial evolution of Zn metal anode via in situ AFM in organic and aqueous electrolytes,respectively.The processes of uneven nucleation,dendrite growth,the Zn O formation and the dissolution of Zn substrate are directly probed in aqueous electrolyte,which induces interfacial deterioration and ultimately results in battery failure.In organic electrolyte,the in situ observations show that the homogeneous nuclei form on the Zn surface to induce the dendrite-free deposition,however,exhibiting poor Zn plating/stripping reversibility.This work delves into the dynamic evolution and electrochemical behaviors regulated by solvents,which provides in-depth understanding of structure-reactivity correlations and further interfacial engineering.展开更多
Although it has been widely used to probe the interracial property, dynamics, and reactivity, the surface potential remains intractable for directly being measured, especially for charged particles in aqueous solution...Although it has been widely used to probe the interracial property, dynamics, and reactivity, the surface potential remains intractable for directly being measured, especially for charged particles in aqueous solutions. This paper presents that the surface potential is strongly dependent on the Hofmeister effect, and the theory including ion polarization and ionic correlation shows significant improvement compared with the classical theory. Ion polarization causes a strong Hofmeister effect and further dramatic decrease to surface potential, especially at low concentration; in contrast, ionic correlation that is closely associated with potential decay distance overestimates surface potential and plays an increasing role at higher ionic concentrations. Contributions of ion polarization and ionic correlation are respectively assessed, and a critical point is detected where their contributions can be exactly counteracted. Ionic correlation can be almost neglected at low ionic concentrations, while ion polarization, albeit less important at high concentrations, should be considered across the entire concentration range. The results thus obtained are applicable to other interfacial processes.展开更多
In order to improve the healing performance and increase the service life of the polymer matrix composites, microcapsules were prepared by interracial polymerization process with urea formaldehyde resin and epoxy resi...In order to improve the healing performance and increase the service life of the polymer matrix composites, microcapsules were prepared by interracial polymerization process with urea formaldehyde resin and epoxy resin E-51 as the wall material and core material separately. The effects of core/shell mass ratio and emulsifier on the distribution, topography and encapsulation rate of microcapsules were investigated. By optimizing the conditions, microcapsules with little particle size, well dispersion and compact surface were prepared. The distribution, topography, stability and compositions of the microcapsules were characterized using Nano-2s, optical microscope, scanning electron microscopy, thermal analysis and Fourier transform infrared spectroscopy. The osmosis performance of the microcapsules was evaluated. The experimental results showed that the ratio of core/shell materials （1：1） and 1% DBS as emulsifier were optimum preparation conditions and the encapsulation rate was 62.5%. The microcapsules can be synthesized successfully with mean diameter 548.6 nm and exhibit a good chemical stability below 225 ℃. The FTIR result indicated that urea-formaldehyde resin was formed and the core materials were successfully encapsulated in urea-formaldehyde shell. Osmosis performance evaluation showed that the microcapsules were well coated and slowly osmosed.展开更多
The surface morphology of Zn O films at different annealing temperatures and the performance of polymer solar cells(PSCs) with Zn O as the electron transport layer are studied.The low temperature sol-gel processed Zn ...The surface morphology of Zn O films at different annealing temperatures and the performance of polymer solar cells(PSCs) with Zn O as the electron transport layer are studied.The low temperature sol-gel processed Zn O film has smoother surface than that in higher temperature,which results in the best photovoltaic performance with a power conversion efficiency(PCE) of 3.66% for P3HT:PC61BM based solar cell.With increasing annealing temperature,the photovoltaic performance first deceases and then increases.It could be ascribed to the synergy effects of interface area,the conductivity and surface energy of Zn O film and series resistance of devices.展开更多
基金financially supported by the National Key R&D Program of China (No. 2021YFB2500300)the CAS Project for Young Scientists in Basic Research (No. YSBR-058)+1 种基金the National Science Foundation of China (No. 22205241)the National Postdoctoral Program for Innovative Talents (No. BX20220306) of the Chinese Postdoctoral Science Foundation。
文摘Unstable electrode/electrolyte interfaces and heterogeneous Zn deposition would reduce the Coulombic efficiency and cycle life of Zn metal batteries(ZMBs). Applying water-in-salt(WIS) electrolytes has proven to be an effective strategy to address the above issues. However, an understanding of the reaction mechanisms on the Zn anode at nanoscale is still elusive. Here we utilize in situ atomic force microscopy to visualize the solid electrolyte interphase(SEI) formation and Zn deposition/dissolution processes in WIS electrolyte and construct relationships between interfacial behavior and electrochemical performance. The formation processes, chemical properties, and structure of the on-site formed SEI are deeply explored.The SEI with a “plum-pudding” model can guide uniform Zn deposition and reversible dissolution. Mechanistic understanding of the interfacial evolution of the SEI layer and Zn deposition/dissolution has been achieved and will benefit the structural optimization and interfacial engineering of ZMBs.
基金financially supported by the CAS Project for Young Scientists in Basic Research(No.YSBR-058)the National Key R&D Program of China(No.2021YFB2500300)+1 种基金the National Natural Science Foundation of China(Nos.92372125,22205241)the National Postdoctoral Program for Innovative Talents(No.BX20220306)of the Chinese Postdoctoral Science Foundation。
文摘Zn metal batteries are highly attractive because of their high theoretical specific capacity,intrinsic safety and resource availability.However,further development is significantly hindered by low Coulomb efficiency,which is closely linked to reaction processes occurring at electrode/electrolyte interfaces.Herein,we have achieved a real-time visualization and comprehensive analysis of the interfacial evolution of Zn metal anode via in situ AFM in organic and aqueous electrolytes,respectively.The processes of uneven nucleation,dendrite growth,the Zn O formation and the dissolution of Zn substrate are directly probed in aqueous electrolyte,which induces interfacial deterioration and ultimately results in battery failure.In organic electrolyte,the in situ observations show that the homogeneous nuclei form on the Zn surface to induce the dendrite-free deposition,however,exhibiting poor Zn plating/stripping reversibility.This work delves into the dynamic evolution and electrochemical behaviors regulated by solvents,which provides in-depth understanding of structure-reactivity correlations and further interfacial engineering.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.41371249,41201223,and 41101223)the Fundamental Research Funds for the Central Universities,China(Grant No.XDJK2015C059)
文摘Although it has been widely used to probe the interracial property, dynamics, and reactivity, the surface potential remains intractable for directly being measured, especially for charged particles in aqueous solutions. This paper presents that the surface potential is strongly dependent on the Hofmeister effect, and the theory including ion polarization and ionic correlation shows significant improvement compared with the classical theory. Ion polarization causes a strong Hofmeister effect and further dramatic decrease to surface potential, especially at low concentration; in contrast, ionic correlation that is closely associated with potential decay distance overestimates surface potential and plays an increasing role at higher ionic concentrations. Contributions of ion polarization and ionic correlation are respectively assessed, and a critical point is detected where their contributions can be exactly counteracted. Ionic correlation can be almost neglected at low ionic concentrations, while ion polarization, albeit less important at high concentrations, should be considered across the entire concentration range. The results thus obtained are applicable to other interfacial processes.
基金Founded by the National Natural Science Foundation of China(21106022)the Science and Technology Planning Project of Guangdong Province,China(2013B010404045)the Educational Commission of Guangdong Province,China(Yq2013100)
文摘In order to improve the healing performance and increase the service life of the polymer matrix composites, microcapsules were prepared by interracial polymerization process with urea formaldehyde resin and epoxy resin E-51 as the wall material and core material separately. The effects of core/shell mass ratio and emulsifier on the distribution, topography and encapsulation rate of microcapsules were investigated. By optimizing the conditions, microcapsules with little particle size, well dispersion and compact surface were prepared. The distribution, topography, stability and compositions of the microcapsules were characterized using Nano-2s, optical microscope, scanning electron microscopy, thermal analysis and Fourier transform infrared spectroscopy. The osmosis performance of the microcapsules was evaluated. The experimental results showed that the ratio of core/shell materials （1：1） and 1% DBS as emulsifier were optimum preparation conditions and the encapsulation rate was 62.5%. The microcapsules can be synthesized successfully with mean diameter 548.6 nm and exhibit a good chemical stability below 225 ℃. The FTIR result indicated that urea-formaldehyde resin was formed and the core materials were successfully encapsulated in urea-formaldehyde shell. Osmosis performance evaluation showed that the microcapsules were well coated and slowly osmosed.
基金supported by the Independent Innovation Foundation of Shandong University(No.2014YQ015)
文摘The surface morphology of Zn O films at different annealing temperatures and the performance of polymer solar cells(PSCs) with Zn O as the electron transport layer are studied.The low temperature sol-gel processed Zn O film has smoother surface than that in higher temperature,which results in the best photovoltaic performance with a power conversion efficiency(PCE) of 3.66% for P3HT:PC61BM based solar cell.With increasing annealing temperature,the photovoltaic performance first deceases and then increases.It could be ascribed to the synergy effects of interface area,the conductivity and surface energy of Zn O film and series resistance of devices.
