Next the samples were coated with a thin Au layer (about 20 nm thick) deposited with a Cressington 208HR. Fine meshed TiO powder (0.2 g, 99.99% purity, maintop.com.cn, Beijing) was loaded at the center of a 5 cm long quartz boat.
Next the samples were coatedwith a thin Au layer (about 20 nm thick) depositedwith a Cressington 208HR. Fine meshed TiO powder(0.2 g, 99.99% purity, maintop.com.cn, Beijing) wasloaded at the center of a 5 cm long quartz boat.