A new material based on the self-assembly of palladium nanoparticles by a thiacalix[4]arene (TCA) based Cd(II) complex is synthesized. Hydrophobic interactions between tert-butyl groups on either ends of the TCA–cadmium complex and palladium nanoparticles generate self-assembled material 5. The material shows its potential application as a heterogeneous recyclable catalyst for the reduction of 4-nitrophenol (4-NP). The rate constants for catalyst 5 observed in 1st and 5th catalytic cycles were 0.117 min⁻¹ and 0.109 min⁻¹, respectively, revealing the efficiency of the catalyst.