This result confirms our previous data suggesting that most of the lattice defects are formed at the early stages of crystal growth and are thus located at the center of the crystals.Using TBPOH at 1158C to form multi-hollow crystals, removed only partially the inner part of the crystals and the orthorhombic symmetry of the zeolite lattice was preserved. Moreover,the singlet at 24.48 was even more pronounced after citric acid treatment, suggesting that the acid could create additional defects, which could possibly explain why hollow silicalite-1 appeared less stable after acid treatment in the steam reforming of methane at 900℃.