Nanosized metal （Pt or Pd）-decorated TiO2 nanofibers （NFs） were synthesized by a wet impregnation method. CdSe quantum dots （QDs） were then anchored onto the metal-decorated TiO2 NFs. The photocatalytic performa...Nanosized metal （Pt or Pd）-decorated TiO2 nanofibers （NFs） were synthesized by a wet impregnation method. CdSe quantum dots （QDs） were then anchored onto the metal-decorated TiO2 NFs. The photocatalytic performance of these catalysts was tested for activation and reduction of CO2 under UV-B light. Gas chromatographic analysis indicated the formation of methanol, formic acid, and methyl formate as the primary products. In the absence of CdSe QDs, Pd-decorated TiO2 NFs were found to exhibit enhanced performance compared to Pt-decorated TiO2 NFs for methanol production. However, in the presence of CdSe, Pt-decorated TiO2 NFs exhibited higher selectivity for methanol, typically producing -90 ppmg^-1.h^-1 methanol. The CO2 photoreduction mechanism is proposed to take place via a hydrogenation pathway from first principles calculations, which complement the experimental observations.展开更多
New strategies for spatially controlled growth of human neurons may provide viable solutions to treat and recover peripheral or spinal cord injuries.While topography cues are known to promote attachment and direct pro...New strategies for spatially controlled growth of human neurons may provide viable solutions to treat and recover peripheral or spinal cord injuries.While topography cues are known to promote attachment and direct proliferation of many cell types,guided outgrowth of human neurites has been found difficult to achieve so far.Here,three-dimensional(3D)micropatterned carbon nanotube(CNT)templates are used to effectively direct human neurite stem cell growth.By exploiting the mechanical flexibility,electrically conductivity and texture of the 3D CNT micropillars,a perfect environment is created to achieve specific guidance of human neurites,which may lead to enhanced therapeutic effects within the injured spinal cord or peripheral nerves.It is found that the 3D CNT micropillars grant excellent anchoring for adjacent neurites to form seamless neuronal networks that can be grown to any arbitrary shape and size.Apart from clear practical relevance in regenerative medicine,these results using the CNT based templates on Si chips also can pave the road for new types of microelectrode arrays to study cell network electrophysiology.展开更多
文摘Nanosized metal （Pt or Pd）-decorated TiO2 nanofibers （NFs） were synthesized by a wet impregnation method. CdSe quantum dots （QDs） were then anchored onto the metal-decorated TiO2 NFs. The photocatalytic performance of these catalysts was tested for activation and reduction of CO2 under UV-B light. Gas chromatographic analysis indicated the formation of methanol, formic acid, and methyl formate as the primary products. In the absence of CdSe QDs, Pd-decorated TiO2 NFs were found to exhibit enhanced performance compared to Pt-decorated TiO2 NFs for methanol production. However, in the presence of CdSe, Pt-decorated TiO2 NFs exhibited higher selectivity for methanol, typically producing -90 ppmg^-1.h^-1 methanol. The CO2 photoreduction mechanism is proposed to take place via a hydrogenation pathway from first principles calculations, which complement the experimental observations.
基金G.S.L.and L.Y-O.acknowledge the support from the Academy of Finland(Nos.320090,317437 and 286990,respectively)J.T.K.and T.J.acknowledge the support from the Finnish Cultural Foundation Pirkanmaa Regional Fund(No.50151501)+1 种基金the Central Fund(#00150312),respectively.S.N.,T.J.and M.K.acknowledge the support from the Academy of Finland(S.N.and T.J.No.312414 and M.K.No.312409)Business Finland(former Tekes,Human Spare Parts project).This work made use of the electron microscopy and clean-room facilities at the Centre of Microscopy and Nanotechnology,at the University of Oulu.The authors also acknowledge the Tampere Imaging Facility(TIF)and the Tampere CellTech Laboratories for their service.
文摘New strategies for spatially controlled growth of human neurons may provide viable solutions to treat and recover peripheral or spinal cord injuries.While topography cues are known to promote attachment and direct proliferation of many cell types,guided outgrowth of human neurites has been found difficult to achieve so far.Here,three-dimensional(3D)micropatterned carbon nanotube(CNT)templates are used to effectively direct human neurite stem cell growth.By exploiting the mechanical flexibility,electrically conductivity and texture of the 3D CNT micropillars,a perfect environment is created to achieve specific guidance of human neurites,which may lead to enhanced therapeutic effects within the injured spinal cord or peripheral nerves.It is found that the 3D CNT micropillars grant excellent anchoring for adjacent neurites to form seamless neuronal networks that can be grown to any arbitrary shape and size.Apart from clear practical relevance in regenerative medicine,these results using the CNT based templates on Si chips also can pave the road for new types of microelectrode arrays to study cell network electrophysiology.
