<p>In this work, the potential of nanocages (Cu-C₈₄ and Cu-Si₈₄) and nanotubes (Cu-CNT(9, 0) and Cu-SiNT(9, 0)) for SO₂ hydro-desulfurization to produce the H₂S are examined via acceptable mechanisms. The ∆E_adoption and ∆E_formation of Cu-C₈₄, Cu-Si₈₄, Cu-doped C and Si nanotubes (9, 0) are acceptable values to confirm the stability of nanostructures. The ∆E_adsorption of SO₂, SO, S, O, SH, OH, H₂S and H₂O on Cu-C₈₄ are -4.38, -3.75, -2.68, -3.03, -0.14, -0.06, -0.21 and -0.10 eV, respectively. The H₂O and H₂S molecules are desorbed from nanostructures, physically. The ∆E_formation of Cu-C₈₄, Cu-Si₈₄, Cu-doped C and Si nanotubes (9, 0) are -2.91, -3.06, -3.39 and -3.46 eV, respectively. Results indicated that the hydrogenation of S* has more negative ΔG_reaction than hydrogenation of O* on Cu-C₈₄, Cu-Si₈₄, Cu-doped C and Si nanotubes (9, 0), significantly. The hydrogenation of S* has lower E_activation than hydrogenation of O* on surfaces of catalysts. The ΔG_reaction of S → SH → H₂S reaction on Cu-Si₈₄ and Cu-doped Si nanotube (9, 0) are more negative than Cu-C₈₄ and Cu-doped C nanotube (9, 0). Finally, the Cu-doped C and Si nanotubes (9, 0) as effective nano-catalysts for SO₂ hydro-desulfurization to H₂S production are proposed with high performance.</p>