A previous study shows that polymers such as PEG (poly(ethylene
glycol)) and PVP (polyvinyl pyrrolidone) are useful components in the
formation of one- and zero-dimension nano-sized materials. Li and
coworkers successfully prepared ZnO nanowires and nanorods using a
short-chain PEG-assisted pathway [13]. Chirakkal et al. presented the
polymer-assisted growth of molybdenum oxide whiskers [14]. Xiong
et al. prepared Al2O3–TiO2 composite nanoparticles using a sol-gel
method with PEG as a gelling agent [15]. Polymeric materials often
serve as stabilizers for metal colloids, preventing their agglomeration
and precipitation [16], i.e. steric stabilization. Due to the ether oxygen
groups with rich electrons in its chain, PEG is able to form complexes
with metal cations and enhance the homogeneous mixing of metal
cations [17]. Metal cations can easily disperse in a solution at the