In the first step, yttrium nitrate is dissolved and completely ionized in the distilled water. When Y2O3 powder is mixed with this yttrium nitrate solution, the Y2O3 is dissolved to generate Y3+ and (OH)− ions, which then react to form Y(OH)3. In turn, the Y(OH)3 reacts with the remaining H+ and NO3- ions to form Y4O(OH)9NO3 during CSP. The amount of NO3- increases with increasing amount of yttrium nitrate and the reaction in Eq(4) occurs continuously. Therefore,the peak intensity of Y4O(OH)9NO3 increases with increasing amount of Y4O(OH)9NO3. However, the peak intensity of Y(OH)3 increases as the amount of yttrium nitrate is decreased because the amount of NO3- decreases and the reaction in Eq(4) occurs less frequently.