A nanosized crack-free thin film of ZnO synthesis by AACVD method for photoelectrochemical green hydrogen production

A mononuclear single source zinc precursor [Zn (OAc)
2
(dmae)
2
] (dmae = N, N dimethylaminoethanol, OAc =
acetate) (I), was synthesized using vacuum line and glove box technique and used for the fabrication of zinc
oxide (ZnO) thin films via aerosol assisted chemical vapour deposition technique (AACVD). The precursor (I) was
characterized structurally, morphologically, and optically using XRD, FESEM and UV–visible spectroscopy. [Zn
(OAc)
2
(dmae)
2
] (I) having low decomposition temperature besides excellent solubility in organic solvents makes
it a perfect precursor for producing ZnO thin films. The structural analysis confirmed the growth of crystalline
and single-phase ZnO thin film. The morphological analysis confirmed the presence of uniformly distributed
grains of ZnO on the surface of the substrate. The optical properties were examined using an optical spectrometer
in a range between 200 and 700 nm. The XRD analysis of the synthesized ZnO film on fluorine-doped tin oxide
(FTO) reveals its crystalline nature, with a distinct hexagonal wurtzite structure. Moreover, EDX confirmed the
presence of oxygen and Zn peaks and FESEM analysis revealed the presence of a uniform, homogeneous, and
consistent ZnO thin layer on the FTO substrate. Additionally, Tauc’s calculation was engaged to estimate the
energy band gap of the deposited film of ZnO, revealing a value of approximately 3.45 eV. Likewise, the water
splitting was carried out for green hydrogen production via photoelectrochemical (PEC) measurements,
revealing a notable enhancement in photocurrent when exposed to 150 W halogen light with active potential
windows of 0 - 1.5 Vin contrast to the dark condition.