Development of molecular precursors for deposition of indium sulphide thin film electrodes for photoelectrochemical applications
作者:Muhammad Ali Ehsan、T. A. Nirmal Peiris、K. G. Upul Wijayantha、Marilyn M. Olmstead、Zainudin Arifin、Muhammad Mazhar、K. M. Lo、Vickie McKee
DOI:10.1039/c3dt50781e
日期:——
Symmetrical and unsymmetrical dithiocarbamato pyridine solvated and non-solvated complexes of indium(III) with the general formula [In(S2CNRR′)3]·n(py) [where py = pyridine; R,R′ = Cy, n = 2 (1); R,R′ = iPr, n = 1.5 (2); NRR′ = Pip, n = 0.5 (3) and R = Bz, R′ = Me, n = 0 (4)] have been synthesized. The compositions, structures and properties of these complexes have been studied by means of microanalysis, IR and 1H-NMR spectroscopy, X-ray single crystal and thermogravimetric (TG/DTG) analyses. The applicability of these complexes as single source precursors (SSPs) for the deposition of β-In2S3 thin films on fluorine-doped SnO2 (FTO) coated conducting glass substrates by aerosol-assisted chemical vapour deposition (AACVD) at temperatures of 300, 350 and 400 °C is studied. All films have been characterized by powder X-ray diffraction (PXRD) and energy dispersive X-ray analysis (EDX) for the detection of phase and stoichiometry of the deposit. Scanning electron microscopy (SEM) studies reveal that precursors (1)–(4), irrespective of different metal ligand design, generate comparable morphologies of β-In2S3 thin films at different temperatures. Direct band gap energies of 2.2 eV have been estimated from the UV-vis spectroscopy for the β-In2S3 films fabricated from precursors (1) and (4). The photoelectrochemical (PEC) properties of β-In2S3 were confirmed by recording the current–voltage plots under light and dark conditions. The plots showed anodic photocurrent densities of 1.25 and 0.65 mA cm−2 at 0.23 V vs. Ag/AgCl for the β-In2S3 films made at 400 and 350 °C from the precursors (1) and (4), respectively. The photoelectrochemical performance indicates that the newly synthesised precursors are highly useful in fabricating β-In2S3 electrodes for solar energy harvesting and optoelectronic application.
通式为 [In(S2CNRR′)3]-n(py) [其中 py = 吡啶;R,R′ = Cy,n = 2 (1);R,R′ = iPr,n = 1.5 (2); NRR′ = Pip, n = 0.5 (3) 和 R = Bz, R′ = Me, n = 0 (4)] 已被合成。通过显微分析、红外光谱和 1H-NMR 光谱、X 射线单晶和热重(TG/DTG)分析,对这些复合物的组成、结构和性质进行了研究。研究了这些复合物作为单源前驱体 (SSP) 在 300、350 和 400 °C 温度下通过气溶胶辅助化学气相沉积 (AACVD) 在氟掺杂 SnO2 (FTO) 涂层导电玻璃基底上沉积 β-In2S3 薄膜的适用性。所有薄膜都通过粉末 X 射线衍射 (PXRD) 和能量色散 X 射线分析 (EDX) 进行了表征,以检测沉积物的相位和化学计量。扫描电子显微镜(SEM)研究表明,前驱体(1)-(4),无论金属配体设计如何,在不同温度下生成的 β-In2S3 薄膜形貌相当。根据紫外-可见光谱,前体(1)和(4)制备的 β-In2S3 薄膜的直接带隙能估计为 2.2 eV。通过记录光照和黑暗条件下的电流-电压图,证实了 β-In2S3 的光电化学(PEC)特性。图中显示,在 0.23 V 电压下,以前驱体 (1) 和 (4) 为原料在 400 ℃ 和 350 ℃ 制成的 β-In2S3 薄膜对 Ag/AgCl 的阳极光电流密度分别为 1.25 和 0.65 mA cm-2。光电化学性能表明,新合成的前驱体在制造用于太阳能收集和光电应用的 β-In2S3 电极方面非常有用。