Fabrication of periodically micro-patterned magnetite nanoparticles by laser interference controlled electrodeposition

This paper introduces a  laser interference controlled electrochemical deposition (LIED) method  for  direct  fabrication  of  periodically  micro-patterned  magnetite  (Fe3O4) nanoparticles  (NPs). In this work, Fe3O4 NPs were controllably synthesized on the areas where  the  photoconductive  electrode  was  exposed  to  the  periodically  patterned 
interferometric laser  irradiation  during the  electrodeposition. Thus,  the micro-pattern of Fe3O4  NPs was controlled by  interferometric laser  pattern and the crystallization of  the particles  was  controlled  by  laser  interference  intensity  and  electrochemical  deposition conditions.  The  bottom-up  electrochemical  approach  was  combined  with  a  top  down 
laser interference methodology. This maskless  method allows for in situ fabrication of periodically patterned magnetite NPs on the micro-scale by electrodeposition under room temperature and atmospheric pressure conditions.  In the experiment, Fe3O4 NPs with the mean grain size below 100  nm  in the  pattern of 5 μm line array were achieved within the deposition time of 100 seconds.  The  experiment  results  have  shown  that  the  proposed method is a  one-step  approach in fabricating  large areas  of  periodically micro-patterned magnetite NPs.