铜基氧化物表面的氧化物种可以增强CO_(2)吸附,降低含氧中间体的结合能,从而提高电还原CO_(2)的一步还原产物的产率.鉴于此,在还原过程中,Cu_(2)O上的残留氧通过Sn^(2+)稳定,并且残留氧的保留通过原位拉曼光谱(Cu–O_(ads))得到了证实....铜基氧化物表面的氧化物种可以增强CO_(2)吸附,降低含氧中间体的结合能,从而提高电还原CO_(2)的一步还原产物的产率.鉴于此,在还原过程中,Cu_(2)O上的残留氧通过Sn^(2+)稳定,并且残留氧的保留通过原位拉曼光谱(Cu–O_(ads))得到了证实.同时,原位拉曼光谱和密度泛函理论计算结果证明,由于残留氧的存在,一氧化碳中间体在SnO/Cu_(2)O催化剂的吸附能比Cu_(2)O催化剂明显降低.这使得其在-0.8 V (相对于可逆氢电极)的电位下获得高达97.5%的法拉第效率.铜基氧化物催化剂的氧稳定策略对设计高性能电还原CO_(2)催化剂具有指导意义.展开更多
Functional nanostructures are exploited for a variety of cutting-edge fields including plasmonics,metasurfaces,and biosensors,just to name a few.Some applications require nanostructures with uniform feature sizes whil...Functional nanostructures are exploited for a variety of cutting-edge fields including plasmonics,metasurfaces,and biosensors,just to name a few.Some applications require nanostructures with uniform feature sizes while others rely on spatially varying morphologies.However,fine manipulation of the feature size over a large area remains a substantial challenge because mainstream approaches to precise nanopatterning are based on low-throughput pixel-by-pixel processing,such as those utilizing focused beams of photons,electrons,or ions.In this work,we provide a solution toward wafer-scale,arbitrary modulation of feature size distribution by introducing a lithographic portfolio combining interference lithography(IL)and grayscale-patterned secondary exposure(SE).Employed after the high-throughput IL,a SE with patterned intensity distribution spatially modulates the dimensions of photoresist nanostructures.Based on this approach,we successfully fabricated 4-inch wafer-scale nanogratings with uniform linewidths of<5%variation,using grayscale-patterned SE to compensate for the linewidth difference caused by the Gaussian distribution of the laser beams in the IL.Besides,we also demonstrated a wafer-scale structural color painting by spatially modulating the filling ratio to achieve gradient grayscale color using SE.展开更多
Metallic nanostructures are becoming increasingly important for both fundamental research and practical devices.Many emerging applications employing metallic nanostructures often involve unconventional substrates that...Metallic nanostructures are becoming increasingly important for both fundamental research and practical devices.Many emerging applications employing metallic nanostructures often involve unconventional substrates that are flexible or nonplanar,making direct lithographic fabrication very difficult.An alternative approach is to transfer prefabricated structures from a conventional substrate;however,it is still challenging to maintain high fidelity and a high yield in the transfer process.In this paper,we propose a high-fidelity,clean nanotransfer lithography method that addresses the above challenges by employing a polyvinyl acetate(PVA)film as the transferring carrier and promoting electrostatic adhesion through triboelectric charging.The PVA film embeds the transferred metallic nanostructures and maintains their spacing with a remarkably low variation of<1%.When separating the PVA film from the donor substrate,electrostatic charges are generated due to triboelectric charging and facilitate adhesion to the receiver substrate,resulting in a high large-area transfer yield of up to 99.93%.We successfully transferred the metallic structures of a variety of materials(Au,Cu,Pd,etc.)with different geometries with a<50-nm spacing,high aspect ratio(>2),and complex 3D structures.Moreover,the thin and flexible carrier film enables transfer on highly curved surfaces,such as a single-mode optical fiber with a curvature radius of 62.5μm.With this strategy,we demonstrate the transfer of metallic nanostructures for a compact spectrometer with Cu nanogratings transferred on a convex lens and for surface-enhanced Raman spectroscopy(SERS)characterization on graphene with reliable responsiveness.展开更多
基金supported by Shenzhen Science and Technology Foundation of Nanshan (K20799112)the Basic Research Project of the Science and Technology Innovation Commission of Shenzhen (JCYJ20200109141640095)+4 种基金the National Natural Science Foundation of China (21875097)Shenzhen Key Laboratory of Interfacial Science and Engineering of Materials (ZDSYS20200421111401738)supported by the National Supercomputer Center in Guangzhouthe National Supercomputing Center in Shenzhen (Shenzhen Cloud Computing Center)the Center for Computational Science and Engineering at SUSTech。
文摘铜基氧化物表面的氧化物种可以增强CO_(2)吸附,降低含氧中间体的结合能,从而提高电还原CO_(2)的一步还原产物的产率.鉴于此,在还原过程中,Cu_(2)O上的残留氧通过Sn^(2+)稳定,并且残留氧的保留通过原位拉曼光谱(Cu–O_(ads))得到了证实.同时,原位拉曼光谱和密度泛函理论计算结果证明,由于残留氧的存在,一氧化碳中间体在SnO/Cu_(2)O催化剂的吸附能比Cu_(2)O催化剂明显降低.这使得其在-0.8 V (相对于可逆氢电极)的电位下获得高达97.5%的法拉第效率.铜基氧化物催化剂的氧稳定策略对设计高性能电还原CO_(2)催化剂具有指导意义.
基金partially supported by the Research Grants Council of the Hong Kong Special Administrative Region(Awards no.17207419,17209320,C7018-20G,and AoE/P-701/20)the Platform Technology Funding program,and the Seed Funding Program for Basic Research(202011159235 and 202010160046)the University of Hong Kong,and Shenzhen Government(Grant no.K20799112).
文摘Functional nanostructures are exploited for a variety of cutting-edge fields including plasmonics,metasurfaces,and biosensors,just to name a few.Some applications require nanostructures with uniform feature sizes while others rely on spatially varying morphologies.However,fine manipulation of the feature size over a large area remains a substantial challenge because mainstream approaches to precise nanopatterning are based on low-throughput pixel-by-pixel processing,such as those utilizing focused beams of photons,electrons,or ions.In this work,we provide a solution toward wafer-scale,arbitrary modulation of feature size distribution by introducing a lithographic portfolio combining interference lithography(IL)and grayscale-patterned secondary exposure(SE).Employed after the high-throughput IL,a SE with patterned intensity distribution spatially modulates the dimensions of photoresist nanostructures.Based on this approach,we successfully fabricated 4-inch wafer-scale nanogratings with uniform linewidths of<5%variation,using grayscale-patterned SE to compensate for the linewidth difference caused by the Gaussian distribution of the laser beams in the IL.Besides,we also demonstrated a wafer-scale structural color painting by spatially modulating the filling ratio to achieve gradient grayscale color using SE.
基金supported by the Research Grants Council of the Hong Kong Special Administrative Region (Awards No.17207419,17209320,C7018-20G,and AoE/P-701/20)the Platform Technology Funding programme,and the Seed Funding Programme for Basic Research (202011159235 and 202010160046)of the University of Hong KongShenzhen Government (Grant No.K20799112).
文摘Metallic nanostructures are becoming increasingly important for both fundamental research and practical devices.Many emerging applications employing metallic nanostructures often involve unconventional substrates that are flexible or nonplanar,making direct lithographic fabrication very difficult.An alternative approach is to transfer prefabricated structures from a conventional substrate;however,it is still challenging to maintain high fidelity and a high yield in the transfer process.In this paper,we propose a high-fidelity,clean nanotransfer lithography method that addresses the above challenges by employing a polyvinyl acetate(PVA)film as the transferring carrier and promoting electrostatic adhesion through triboelectric charging.The PVA film embeds the transferred metallic nanostructures and maintains their spacing with a remarkably low variation of<1%.When separating the PVA film from the donor substrate,electrostatic charges are generated due to triboelectric charging and facilitate adhesion to the receiver substrate,resulting in a high large-area transfer yield of up to 99.93%.We successfully transferred the metallic structures of a variety of materials(Au,Cu,Pd,etc.)with different geometries with a<50-nm spacing,high aspect ratio(>2),and complex 3D structures.Moreover,the thin and flexible carrier film enables transfer on highly curved surfaces,such as a single-mode optical fiber with a curvature radius of 62.5μm.With this strategy,we demonstrate the transfer of metallic nanostructures for a compact spectrometer with Cu nanogratings transferred on a convex lens and for surface-enhanced Raman spectroscopy(SERS)characterization on graphene with reliable responsiveness.
