Synthesis and characterization of pure MgAPO-36 and CoAPO-36 films on porous substrates

The MgAPO-36 molecular sieve films on porous α-Al₂O ₃ substrates were synthesized under different n_mg/np ratios by using in situ hydrothermal crystallization. The influence of n _mg/np on the microstructure and continuity of the MgAPO-36 film was studied. The CoAPO-36 molecular sieve films on porous α-Al ₂O₃, stainless steel and K₂Ti₆O ₁₃ substrates were fabricated to reveal the effect of the substrate on film formation. SEM observations and XRD data indicate that the pure MgAPO-36 film can be fabricated on porous α-Al₂O₃ substrate with the n_mg/np ratio between 0.08 and 0.24. Especially, the MgAPO-36 film becomes uniform and continuous when the n_mg/np ratio is about 0.10. Although pure CoAPO-36 films can be formed on porous α-Al ₂O₃, stainless steel and K₂Ti₆O ₁₃ substrates, the continuous and uniform CoAPO-36 film can only be synthesized on porous K₂Ti₆O₁₃substrate.