A bioinspired approach to the synthesis of bimetallic CoNi nanoparticles.
Bimetallic CoNi nanoparticles have been prepared within the apoferritin cavity. The protein shell controls size, prevents aggregation, and makes nanoparticles water-soluble. The CoNi series prepared in this way were structurally and magnetically characterized, the resulting magnetic properties varying accordingly with composition (Co(75)/Ni(25), Co(50)/Ni(50), Co(25)/Ni(75)). Co and Ni metals were associated in each nanoparticle, as demonstrated by high-angle annular dark field scanning electron microscopy and electron energy loss spectroscopy (EELS). After intentional oxidation, the CoNi nanoparticles were characterized by EELS, X-ray absorption near edge structure (XANES), and SQUID measurements to evaluate the importance of the oxidation on magnetic properties.
Gálvez
Natividad
N
Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain. ngalvez@ugr.es
Valero
Elsa
E
Ceolin
Marcelo
M
Trasobares
Susana
S
López-Haro
Miguel
M
Calvino
José J
JJ
Domínguez-Vera
José M
JM
D001052:Apoferritins / Q000737:chemistry*; D002384:Catalysis; D003035:Cobalt / Q000737:chemistry*; D003460:Crystallization; D004553:Electric Conductivity; D004563:Electrochemistry / Q000379:methods; D008094:Lithium / Q000737:chemistry*; D008280:Magnetics / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D049329:Nanostructures; D036103:Nanotechnology / Q000379:methods*; D009532:Nickel / Q000737:chemistry*; D010084:Oxidation-Reduction; D010316:Particle Size; D013499:Surface Properties; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
D014867:Water; D003035:Cobalt; D009532:Nickel; D001052:Apoferritins; D008094:Lithium