FIB-SEM tomography is a powerful technique that integrates a focused ion beam(FIB)and a scanning electron microscope(SEM)to capture high-resolution imaging data of nanostructures.This approach involves collecting in-p...FIB-SEM tomography is a powerful technique that integrates a focused ion beam(FIB)and a scanning electron microscope(SEM)to capture high-resolution imaging data of nanostructures.This approach involves collecting in-plane SEM imagesand using FIB to remove material layers for imaging subsequent planes,thereby producing image stacks.However,theseimage stacks in FIB-SEM tomography are subject to the shine-through effect,which makes structures visible from theposterior regions of the current plane.This artifact introduces an ambiguity between image intensity and structures in thecurrent plane,making conventional segmentation methods such as thresholding or the k-means algorithm insufficient.Inthis study,we propose a multimodal machine learning approach that combines intensity information obtained at differentelectron beam accelerating voltages to improve the three-dimensional(3D)reconstruction of nanostructures.By treatingthe increased shine-through effect at higher accelerating voltages as a form of additional information,the proposed methodsignificantly improves segmentation accuracy and leads to more precise 3D reconstructions for real FIB tomography data.展开更多
Bulk nanoporous platinum(np-Pt)samples with a remarkably fine ligament size down to 2 nm and good mechanical robustness were fabricated for the first time by electrochemically dealloying Pt15Cu85 master alloy in 1 mol...Bulk nanoporous platinum(np-Pt)samples with a remarkably fine ligament size down to 2 nm and good mechanical robustness were fabricated for the first time by electrochemically dealloying Pt15Cu85 master alloy in 1 mol L−1 H_(2)SO_(4)at 60℃.The as-prepared np-Pt shows an electrochemically active specific surface area as high as 25 m^(2)/g due to the ultrafine nanostructure.The active surface area remains almost invariable even after 15%macroscopic compressive strain.Furthermore,np-Pt shows considerably high thermal stability due to the low surface diffusivity of Pt.Np-Pt is a promising surface-or interface-controlled functional material,particularly when excellent electrochemical and mechanical performance are necessary due to its high surface-to-volume ratio and mechanical robustness.This work demonstrated the potential application of np-Pt as an electrochemical actuation material.In-situ dilatometry experiments revealed that the surface adsorp-tion-desorption of OH species on np-Pt causes significant strain variations.The proposed np-Pt electrochem-ical actuator shows an operating voltage down to 1.0 V,a large reversible strain amplitude of 0.37%,and a strain energy density of 1.64 MJ/m^(3).展开更多
基金funded by the Deutsche Forschungsgemein-schaft(DFG,German Research Foundation)-SFB 986-Project number 192346071.
文摘FIB-SEM tomography is a powerful technique that integrates a focused ion beam(FIB)and a scanning electron microscope(SEM)to capture high-resolution imaging data of nanostructures.This approach involves collecting in-plane SEM imagesand using FIB to remove material layers for imaging subsequent planes,thereby producing image stacks.However,theseimage stacks in FIB-SEM tomography are subject to the shine-through effect,which makes structures visible from theposterior regions of the current plane.This artifact introduces an ambiguity between image intensity and structures in thecurrent plane,making conventional segmentation methods such as thresholding or the k-means algorithm insufficient.Inthis study,we propose a multimodal machine learning approach that combines intensity information obtained at differentelectron beam accelerating voltages to improve the three-dimensional(3D)reconstruction of nanostructures.By treatingthe increased shine-through effect at higher accelerating voltages as a form of additional information,the proposed methodsignificantly improves segmentation accuracy and leads to more precise 3D reconstructions for real FIB tomography data.
文摘Bulk nanoporous platinum(np-Pt)samples with a remarkably fine ligament size down to 2 nm and good mechanical robustness were fabricated for the first time by electrochemically dealloying Pt15Cu85 master alloy in 1 mol L−1 H_(2)SO_(4)at 60℃.The as-prepared np-Pt shows an electrochemically active specific surface area as high as 25 m^(2)/g due to the ultrafine nanostructure.The active surface area remains almost invariable even after 15%macroscopic compressive strain.Furthermore,np-Pt shows considerably high thermal stability due to the low surface diffusivity of Pt.Np-Pt is a promising surface-or interface-controlled functional material,particularly when excellent electrochemical and mechanical performance are necessary due to its high surface-to-volume ratio and mechanical robustness.This work demonstrated the potential application of np-Pt as an electrochemical actuation material.In-situ dilatometry experiments revealed that the surface adsorp-tion-desorption of OH species on np-Pt causes significant strain variations.The proposed np-Pt electrochem-ical actuator shows an operating voltage down to 1.0 V,a large reversible strain amplitude of 0.37%,and a strain energy density of 1.64 MJ/m^(3).
