The Ni-W gradient deposit with nano-structure was prepared by an electrochemical deposition method.X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDXA) indicate that the crystallite size of the deposit ...The Ni-W gradient deposit with nano-structure was prepared by an electrochemical deposition method.X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDXA) indicate that the crystallite size of the deposit decreases from 10.3nm to 1.5nm and the crystal grating aberrance increases with the increase of W content in the growing direction of the deposit. The structure of deposit changes from crystalline to amorphous stepwise with associated increase of crystal grating aberrance, and presents gradient distribution. These show that the deposit isgradient with nano-structure.展开更多
One-dimensional (1D) ZnO nanostructures have been studied intensively and extensively over the last decade not only for their remarkable chemical and physical properties, but also for their diverse current and futur...One-dimensional (1D) ZnO nanostructures have been studied intensively and extensively over the last decade not only for their remarkable chemical and physical properties, but also for their diverse current and future technological applications. This article gives a comprehensive overview of the progress that has been made within the context of 1D ZnO nanostructures synthesized via wet chemical methods. We will cover the synthetic methodologies and the corresponding growth mechanisms, various nanostructures grown, their doping and alloying, and position-controlled growth on substrates. Finally, we will review their functional properties in catalysis, hydrophobic surface modification, sensing, and electronic, optical, optoelectronic, and energy harvesting devices.展开更多
Catalysts for oxygen and hydrogen evolution reactions (OER/HER) are at the heart of renewable green energy sources such as water splitting. Although incredible efforts have been made to develop efficient catalysts f...Catalysts for oxygen and hydrogen evolution reactions (OER/HER) are at the heart of renewable green energy sources such as water splitting. Although incredible efforts have been made to develop efficient catalysts for OER and HER, great challenges still remain in the development of bifunctional catalysts. Here, we report a novel hybrid of Co3O4 embedded in tubular nanostructures of graphitic carbon nitride (GCN) and synthesized through a facile, large-scale chemical method at low temperature. Strong synergistic effects between Co3O4 and GCN resulted in excellent performance as a bifunctional catalyst for OER and HER. The high surface area, unique tubular nanostructure, and composition of the hybrid made all redox sites easily available for catalysis and provided faster ionic and electronic conduction. The Co3O4@GCN tubular nanostructured (TNS) hybrid exhibited the lowest overpotential (0.12 V) and excellent current density (147 mA/cm^2) in OER, better than benchmarks IrO2 and RuO2, and with superior durability in alkaline media. Furthermore, the Co3O4@GCN TNS hybrid demonstrated excellent performance in HER, with a much lower onset and overpotential, and a stable current density. It is expected that the Co3O4@GCN TNS hybrid developed in this study will be an attractive alternative to noble metals catalysts in large scale water splitting and fuel cells.展开更多
The rational design and synthesis of hierarchically hollow nanostructures with controlled spatial architecture and composition are significant in electrocatalysis owing to their abundant active sites and the expedited...The rational design and synthesis of hierarchically hollow nanostructures with controlled spatial architecture and composition are significant in electrocatalysis owing to their abundant active sites and the expedited electron/mass transfer.Electrocatalytic nitrate reduction to ammonia is of great interest from the points of environmental protection and energy saving.However,the development of this technology is hindered by the lack of efficient nitrate-toammonia electrocatalysts and the kinetically sluggish oxygen evolution reaction at the anode.Herein,a novel self-template conversion method was developed for the synthesis of Co3O4@Ni O hierarchical nanotubes(Co3O4@Ni O HNTs)with Ni O porous nanosheets assembled on Co3O4nanotubes.The as-obtained Co3O4@Ni O HNTs exhibited an outstanding performance for both the cathodic nitrate electroreduction to ammonia reaction and the anodic tetrahydroisoquinolines(THIQs)semi-dehydrogenation to dihydroisoquinolines(DHIQs).Importantly,a two-electrode system of Co3O4@Ni O HNTs||Co3O4@Ni O HNTs was constructed for the simultaneous synthesis of ammonia and DHIQs with high selectivity and robust stability.展开更多
Construction of functional porous titanium scaffold is drawing ever growing attention, due to its effectiveness in solving the mechanical mismatch between titanium implant and bone tissue. However, the poor water perm...Construction of functional porous titanium scaffold is drawing ever growing attention, due to its effectiveness in solving the mechanical mismatch between titanium implant and bone tissue. However, the poor water permeability as well as the problem in achieving uniform surface modification inside scaffold hinders the further biomedical application of porous titanium scaffold. In this study, largescale functional Ti O2 nanostructures(nanonetwork, nanoplate and nanowire) were constructed on three-dimensional porous titanium scaffolds surface via an effective hydrothermal treatment method. These nanostructures increase the hydrophilicity of the titanium scaffold surface, facilitating the cell culture medium to penetrate into the inner pore of the scaffold. Zeta potential analyses indicate that the surface electrical properties depend on the nanostructure, with nanowire exhibiting the lowest potential at p H 7.4. The influence of the nano-functionalized scaffold on protein adsorption and cell adhesion was examined. The results indicate that the nano-functionalized surface could modulate protein adsorption and bone marrow derived mesenchymal stem cells(BMSCs) adhesion, with the nanowire functionalized porous scaffold homogeneously promoting protein adsorption and BMSCs adhesion. Our research will facilitate future research on the development of novel functional porous scaffold.展开更多
This paper reports a controllable multi-functional black silicon surface with nanocone-forest structures fabricated by an optimized deep reactive ion etching(DRIE)technique using SF6/C4F8 in cyclic etching-passivation...This paper reports a controllable multi-functional black silicon surface with nanocone-forest structures fabricated by an optimized deep reactive ion etching(DRIE)technique using SF6/C4F8 in cyclic etching-passivation process,which is maskless,effective and controllable.The process conditions are investigated by systematically comparative experiments and core parameters have been figured out,including etching process parameters,pre-treatment,patterned silicon etching and inclined surface etching.Based on the experimental data,the formation mechanism of nanocone shape is developed,which provides a novel view for in-depth understanding of abnormal phenomena observed in the experiments under different process situations.After the optimization of the process parameters,the black silicon surfaces exhibit superhydrophobicity with tunable reflectance.Additionally,the quantitative relationship between nanocones aspect ratio and surface reflectance and static contact angle is obtained,which demonstrates that black silicon surfaces with unique functional properties(i.e.,cross-combination of reflectance and wettability)can be achieved by controlling the morphology of nanostructures.展开更多
A facile,precise,and controllable manufacturing technology is desired for hierarchical functional surfaces.In this work,we successfully manufactured porous metallic glass using a water-dissolution material as template...A facile,precise,and controllable manufacturing technology is desired for hierarchical functional surfaces.In this work,we successfully manufactured porous metallic glass using a water-dissolution material as template and the excellent thermoplastic property of metallic glass.The prepared micro/nanostructures have excellent tunability,and the proposed approach can be used to prepare large-area disordered porous structures and ordered regular arrays with nanoscale replication accuracy.In particular,the disordered porous structure prepared by the dissolvable template strategy exhibits a water contact angle of~140°and an oil contact angle of~0°,making it suitable for oil/water separation.It also shows stable wettability after being soaked in strong acid or alkali environments and maintains a~130°water contact angle and a~4°oil contact angle even after severe wear.The proposed strategy also possesses excellent recycling properties.We reconstructed porous structures on the same surface three times and found no significant change in wettability for each reconstructed porous structure.Our research provides a facile and controllable approach for the preparation of hierarchical porous structures and paves the way for the design of other functional surfaces.展开更多
基金Supported by the National Natural Science Foundation of China (No.59671058)
文摘The Ni-W gradient deposit with nano-structure was prepared by an electrochemical deposition method.X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDXA) indicate that the crystallite size of the deposit decreases from 10.3nm to 1.5nm and the crystal grating aberrance increases with the increase of W content in the growing direction of the deposit. The structure of deposit changes from crystalline to amorphous stepwise with associated increase of crystal grating aberrance, and presents gradient distribution. These show that the deposit isgradient with nano-structure.
文摘One-dimensional (1D) ZnO nanostructures have been studied intensively and extensively over the last decade not only for their remarkable chemical and physical properties, but also for their diverse current and future technological applications. This article gives a comprehensive overview of the progress that has been made within the context of 1D ZnO nanostructures synthesized via wet chemical methods. We will cover the synthetic methodologies and the corresponding growth mechanisms, various nanostructures grown, their doping and alloying, and position-controlled growth on substrates. Finally, we will review their functional properties in catalysis, hydrophobic surface modification, sensing, and electronic, optical, optoelectronic, and energy harvesting devices.
基金Acknowledgements Work at Beijing Institute of Technology was supported by the National Natural Science Foundation of China (Nos. 23171023 and 50972017) and Doctoral Program of the Ministry of Education of China (No. 20101101110026) Work at Peking University was supported by the NSFC-RGC Joint Research Scheme (No. 51361165201), the National Natural Science Foundation of China (Nos. 51125001 and 51172005), Beijing Natural Science Foundation (No. 2122022) and Doctoral Program of the Ministry of Education of China (No. 20120001110078). Deanship of Scientific Research at King Saud University through Prolific Research Group Project (No. PRG-1436-25).
文摘Catalysts for oxygen and hydrogen evolution reactions (OER/HER) are at the heart of renewable green energy sources such as water splitting. Although incredible efforts have been made to develop efficient catalysts for OER and HER, great challenges still remain in the development of bifunctional catalysts. Here, we report a novel hybrid of Co3O4 embedded in tubular nanostructures of graphitic carbon nitride (GCN) and synthesized through a facile, large-scale chemical method at low temperature. Strong synergistic effects between Co3O4 and GCN resulted in excellent performance as a bifunctional catalyst for OER and HER. The high surface area, unique tubular nanostructure, and composition of the hybrid made all redox sites easily available for catalysis and provided faster ionic and electronic conduction. The Co3O4@GCN tubular nanostructured (TNS) hybrid exhibited the lowest overpotential (0.12 V) and excellent current density (147 mA/cm^2) in OER, better than benchmarks IrO2 and RuO2, and with superior durability in alkaline media. Furthermore, the Co3O4@GCN TNS hybrid demonstrated excellent performance in HER, with a much lower onset and overpotential, and a stable current density. It is expected that the Co3O4@GCN TNS hybrid developed in this study will be an attractive alternative to noble metals catalysts in large scale water splitting and fuel cells.
基金financially supported by the National Natural Science Foundation of China(21701122 and 21871206)。
文摘The rational design and synthesis of hierarchically hollow nanostructures with controlled spatial architecture and composition are significant in electrocatalysis owing to their abundant active sites and the expedited electron/mass transfer.Electrocatalytic nitrate reduction to ammonia is of great interest from the points of environmental protection and energy saving.However,the development of this technology is hindered by the lack of efficient nitrate-toammonia electrocatalysts and the kinetically sluggish oxygen evolution reaction at the anode.Herein,a novel self-template conversion method was developed for the synthesis of Co3O4@Ni O hierarchical nanotubes(Co3O4@Ni O HNTs)with Ni O porous nanosheets assembled on Co3O4nanotubes.The as-obtained Co3O4@Ni O HNTs exhibited an outstanding performance for both the cathodic nitrate electroreduction to ammonia reaction and the anodic tetrahydroisoquinolines(THIQs)semi-dehydrogenation to dihydroisoquinolines(DHIQs).Importantly,a two-electrode system of Co3O4@Ni O HNTs||Co3O4@Ni O HNTs was constructed for the simultaneous synthesis of ammonia and DHIQs with high selectivity and robust stability.
基金supported by the National High Technology Research and Development Program of China(2015AA033502)the National Natural Science Foundation of China(51372087,51232002 and 51541201)+3 种基金the Science and Technology Planning Project of Guangdong Province,China(2014A010105048)the Natural Science Foundation of Guangdong Province(2015A030313493 and 2016A030308014)the State Key Laboratory for Mechanical Behavior of Materials,China(20141607)the Technological Projects of Guangzhou,China(201604020110)
文摘Construction of functional porous titanium scaffold is drawing ever growing attention, due to its effectiveness in solving the mechanical mismatch between titanium implant and bone tissue. However, the poor water permeability as well as the problem in achieving uniform surface modification inside scaffold hinders the further biomedical application of porous titanium scaffold. In this study, largescale functional Ti O2 nanostructures(nanonetwork, nanoplate and nanowire) were constructed on three-dimensional porous titanium scaffolds surface via an effective hydrothermal treatment method. These nanostructures increase the hydrophilicity of the titanium scaffold surface, facilitating the cell culture medium to penetrate into the inner pore of the scaffold. Zeta potential analyses indicate that the surface electrical properties depend on the nanostructure, with nanowire exhibiting the lowest potential at p H 7.4. The influence of the nano-functionalized scaffold on protein adsorption and cell adhesion was examined. The results indicate that the nano-functionalized surface could modulate protein adsorption and bone marrow derived mesenchymal stem cells(BMSCs) adhesion, with the nanowire functionalized porous scaffold homogeneously promoting protein adsorption and BMSCs adhesion. Our research will facilitate future research on the development of novel functional porous scaffold.
基金supported by the National Natural Science Foundation of China(Grant Nos.61176103,91023045 and 91323304)the National Hi-Tech Research and Development Program of China("863"Project)(Grant No.2013AA041102)+1 种基金the National Ph.D.Foundation Project(Grant No.20110001110103)the Beijing Natural Science Foundation of China(Grant No.4141002)
文摘This paper reports a controllable multi-functional black silicon surface with nanocone-forest structures fabricated by an optimized deep reactive ion etching(DRIE)technique using SF6/C4F8 in cyclic etching-passivation process,which is maskless,effective and controllable.The process conditions are investigated by systematically comparative experiments and core parameters have been figured out,including etching process parameters,pre-treatment,patterned silicon etching and inclined surface etching.Based on the experimental data,the formation mechanism of nanocone shape is developed,which provides a novel view for in-depth understanding of abnormal phenomena observed in the experiments under different process situations.After the optimization of the process parameters,the black silicon surfaces exhibit superhydrophobicity with tunable reflectance.Additionally,the quantitative relationship between nanocones aspect ratio and surface reflectance and static contact angle is obtained,which demonstrates that black silicon surfaces with unique functional properties(i.e.,cross-combination of reflectance and wettability)can be achieved by controlling the morphology of nanostructures.
基金supported by the Key Basic and Applied Research Program of Guangdong Province,China(2019B030302010)the National Natural Science Foundation of China(52122105,51871157,and 51971150)the National Key Research and Development Program of China(2018YFA0703604)。
文摘A facile,precise,and controllable manufacturing technology is desired for hierarchical functional surfaces.In this work,we successfully manufactured porous metallic glass using a water-dissolution material as template and the excellent thermoplastic property of metallic glass.The prepared micro/nanostructures have excellent tunability,and the proposed approach can be used to prepare large-area disordered porous structures and ordered regular arrays with nanoscale replication accuracy.In particular,the disordered porous structure prepared by the dissolvable template strategy exhibits a water contact angle of~140°and an oil contact angle of~0°,making it suitable for oil/water separation.It also shows stable wettability after being soaked in strong acid or alkali environments and maintains a~130°water contact angle and a~4°oil contact angle even after severe wear.The proposed strategy also possesses excellent recycling properties.We reconstructed porous structures on the same surface three times and found no significant change in wettability for each reconstructed porous structure.Our research provides a facile and controllable approach for the preparation of hierarchical porous structures and paves the way for the design of other functional surfaces.