Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotentia...Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotential and high current density.However,its precise synthesis and the understanding of synergisti-cally catalytic effects remain challenging.Herein,we report a facile method to synthesize the bimetallic Cu and Ni clusters anchored on porous carbon(Cu/Ni-NC)and achieve an enhanced ECO_(2)R.The aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and synchrotron X-ray absorption spectroscopy were employed to verify the metal dispersion and the coordination of Cu/Ni clusters on NC.As a result of this route,the target Cu/Ni-NC exhibits excellent electrocatalytic performance including a stable 30 h electrolysis at 200 mA cm^(-2) with carbon monoxide Faradaic efficiency of∼95.1%using a membrane electrode assembly electrolysis cell.Combined with the in situ analysis of the surface-enhanced Fourier transform infrared spectroelectrochemistry,we propose that the synergistic effects between Ni and Cu can effectively promote the H_(2)O dissociation,thereby accelerate the hydrogenation of CO_(2)to*COOH and the overall reaction process.展开更多
Different cell types make up tissues and organs hierarchically and communicate within a complex, three-dimensional (3D) en- vironment. The in vitro recapitulation of tissue-like structures is meaningful, not only for ...Different cell types make up tissues and organs hierarchically and communicate within a complex, three-dimensional (3D) en- vironment. The in vitro recapitulation of tissue-like structures is meaningful, not only for fundamental cell biology research, but also for tissue engineering (TE). Currently, TE research adopts either the top-down or bottom-up approach. The top-down approach involves defining the macroscopic tissue features using biomaterial scaffolds and seeding cells into these scaffolds. Conversely, the bottom-up approach aims at crafting small tissue building blocks with precision-engineered structural and functional microscale features, using physical and/or chemical approaches. The bottom-up strategy takes advantage of the repeating structural and functional units that facilitate cell-cell interactions and cultures multiple cells together as a functional unit of tissue. In this review, we focus on currently available microscale methods that can control mammalian cells to assemble into 3D tissue-like structures.展开更多
基金This work was supported by National Key R&D Program of China(2020YFE0204500)the National Natural Science Foundation of China(52273277,52072362,52071311)+1 种基金Jilin Province Science and Technology Development Plan Funding Project(20220201112GX)Youth Innovation Promotion Association CAS(2020230 and 2021223).H.X.Z.thanks funding from National Natural Science Foundation of China Outstanding Youth Science Foundation of China(Overseas).These authors thank the staff of beamline BL13SSW at Shanghai Synchrotron Radiation Facility for experiments supports.The authors also gratefully appreciate the support of the morphology characterization and analysis from Prof.Jiuhui Han(Tianjin University of Technology).
文摘Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotential and high current density.However,its precise synthesis and the understanding of synergisti-cally catalytic effects remain challenging.Herein,we report a facile method to synthesize the bimetallic Cu and Ni clusters anchored on porous carbon(Cu/Ni-NC)and achieve an enhanced ECO_(2)R.The aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and synchrotron X-ray absorption spectroscopy were employed to verify the metal dispersion and the coordination of Cu/Ni clusters on NC.As a result of this route,the target Cu/Ni-NC exhibits excellent electrocatalytic performance including a stable 30 h electrolysis at 200 mA cm^(-2) with carbon monoxide Faradaic efficiency of∼95.1%using a membrane electrode assembly electrolysis cell.Combined with the in situ analysis of the surface-enhanced Fourier transform infrared spectroelectrochemistry,we propose that the synergistic effects between Ni and Cu can effectively promote the H_(2)O dissociation,thereby accelerate the hydrogenation of CO_(2)to*COOH and the overall reaction process.
基金supported by Ministry of Science and Technology of China(Grant Nos.2009CB930001 and 2011CB933201)Chinese Academy ofSciences(Grant No.KJCX2-YW-M15)the National Natural ScienceFoundation of China(Grant Nos.20890020,90813032,21025520 and 51073045)
文摘Different cell types make up tissues and organs hierarchically and communicate within a complex, three-dimensional (3D) en- vironment. The in vitro recapitulation of tissue-like structures is meaningful, not only for fundamental cell biology research, but also for tissue engineering (TE). Currently, TE research adopts either the top-down or bottom-up approach. The top-down approach involves defining the macroscopic tissue features using biomaterial scaffolds and seeding cells into these scaffolds. Conversely, the bottom-up approach aims at crafting small tissue building blocks with precision-engineered structural and functional microscale features, using physical and/or chemical approaches. The bottom-up strategy takes advantage of the repeating structural and functional units that facilitate cell-cell interactions and cultures multiple cells together as a functional unit of tissue. In this review, we focus on currently available microscale methods that can control mammalian cells to assemble into 3D tissue-like structures.