With Zn(II) porphyrin as a building block, nano-/microscale MOFs with different morphologies were synthesized as sensitizers for O₂ (forming ¹O₂). The sensitization efficiency was observed to enhance remarkably with the decrease of morphological dimension of the sample. With high sensitization ability, the one-dimensional MOF could selectively photocatalyze the deprotection of oxathiolanes to ketones.