A 30 nm layer of TiO2 was deposited onto the Sb2Se3 films using a thermal atomic layer deposition (ALD) system (PICOSUN, R200). The tetrakis(dimenthylamino)titanium (TDMAT, Aldrich, 99.99%) and milli-Q H2O were employed as the precursors for Ti and O sources, respectively. During deposition, the reaction chamber temperature was kept at 120 o C, while the temperature for the TDMAT was maintained at 85 o C. Pt was used as the hydrogen evolution reaction catalyst. Nominally 2 nm of Pt was sputtered onto the surface of the TiO2 using a sputter coater (LEICA EM ACE600). The thickness of the deposited Pt was monitored by a gold-coated quartz microbalance.