Silver nanoparticles successfully incorporated in titanate nanosheets and synthesized hydrothermally via employing
cetyltrimethylammonium bromide (CTAB) and triblock copolymer (pluronic F127) assisted templates
were thoroughly characterized using transmission electron microscopy-selected area electron diffraction (TEMSAED),
X-ray diffraction, diffuse reflectance UV/visible absorption spectroscopy, N2 sorptiometry, FTIR and
Raman spectroscopy. The dispersed Ag nanoparticles of uniform size (2–3 nm) were found to contact intimately
with titanateF127 nanosheets to show superior crystallinity, wider layer distances and higher surface area and
pore volume (SBET=51.1 m2 g−1, Vp= 0.081 cm3g−1) than Ag/titanateCTAB (7.2 m2 g−1, 0.02 cm3 g−1). This
constructed Ag/titanateF127 exhibits markedly improved electrocatalytic (1.4-fold) and photoelectrocatalytic
(4.0-fold) activities and stabilities towards methanol oxidation than that of Ag/titanateCTAB; as determined using
cyclic voltammetry, linear sweep voltammetry and chronoamperometry. The enhanced activity of Ag/
titanateF127 was also attributed to electron transfer across the interface potential of the composite Ag-titanateF127
as well as the delay of charge recombination that has been substantiated not only via exposed Ag but also
through the non-decomposed carbon template. This enhanced electron transfer and electronic conductivity was
established by impedance spectroscopy, and exhibits the maximum obtained photocurrent density
(2.0 mA cm−2) under visible light illumination (λ > 420 nm, 88 W). The results revealed that the template
F127 had a significant effect not only on enhancing the titanate crystallinity and exhibiting a surface plasmon
resonance band; unlike Ag/titanateCTAB, but also in acquiring a high pore volume value and widened layers,
which all work towards improving the Ag-titanateF127 durability for methanol oxidation. |
