In-fibre chemical and optical sensors based on silver nanocrystals
modified microstructured polymer optical fibres (MPOFs)
were demonstrated. The silver nanocrystals modified MPOFs
were formed by direct chemical reduction of silver ammonia
complex ions on the templates of array holes in the microstructure
polymer optical fibres. The nanotube-like and nanoisland-like
Ag-modified MPOFs could be obtained by adjusting the conditions
of Ag-formation in the air holes of MPOFs. SEM images showed
that the higher concentration of the reaction solution (silver
ammonia 0.5 mol/L, glucose 0.25 mol/L), gave rise to a tubular
silver layer in MPOF, while the lower concentration (silver
ammonia 0.1 M, glucose 0.05 M) produced an island-like Ag
nanocrystal modified MPOF. The tubular Ag-MPOF composite
fibre was conductive and could be directly used as array electrodes
in electrochemical analyses. It displayed high electrochemical
activity on sensing nitrate or nitrite ions. The enhanced
fluorescence of dye molecules was observed when the island
-like Agmodified MPOF was inserted into a fluorescent dye solution.