“…These mechanisms can be divided into two groups: direct methods including soft solution (Okada et al, 2000) and in situ (Okada et al, 2004) methods, and those requiring a secondary hydrothermal treatment, including seeding (Hedlund et al, 1999;Huang et al, 2004;Lassinantti et al, 2000;Cui et al, 2004a), sol-gel routes (Caro et al, 2000), pulsed laser ablation (Deng and Balkus Jr., 2002;Coutinho and Balkus Jr., 2002) and chemical pre-treatments (Caro et al, 2000). Each of these mechanisms has advantages and disadvantages for cost and practicality as well as the level of adhesion of the film (Lassinantti et al, 2000, Okada et al, 2004, and the extent of degradation of the support structure (Okada et al, 2004).…”