The procedure of the hydrothermal treatment (HTT). An aluminum tube (ca. 20 mm in diameter and 150 mm long) was first filled with pure water of 2 mL. The LB sample was put in the tube using a spacer to prevent direct contact of the sample with the water. Finally, the tube was closed by a screw lid using a Teflon tape and immersed in a water bath kept at 80°C.
Miura et al. Nanoscale Research Letters 2013 8:429 doi:10.1186/1556-276X-8-429