Solvothermal synthesis of nanostructured CuInS2 thin films on FTO substrates and their photoelectrochemical properties

► A solvothermal route was developed for large-scale synthesis of CIS thin films on FTO substrates. ► The film quality can be simply adjusted by changing the molar ratios of starting reactants. ► Nanoworm electrode exhibits better PEC performance than the nanosheet electrode.