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Bi2S3nanotubes and nanoparticle in the form of thin films were deposited on fluorine doped SnO2(FTO) coated conducting glass substrates by Aerosol Assisted Chemical Vapor Deposition (AACVD) using tris-(N,N-diethyldithiocarbamato)bismuth(III), [Bi(S2CN(C2H5)2)3]2(1) as a precursor. Thin films were deposited from solutions of (1) in either chloroform, dichloromethane, or a 1:1 mixture of chloroform and toluene at temperature between 350 to 450 °C and characterized by X-ray diffraction (XRD), UV−vis spectroscopy, field emission gun scanning electron microscopy (FEGSEM), and energy dispersive X-ray (EDX) analysis. FEGSEM images of films deposited from chloroform or dichloromethane exhibit well-defined and evenly distributed nanotubes with an average internal diameter of 40 nm. Films deposited from chloroform/toluene, on the other hand, have compact nanostuctured morphology. Bandgaps of 1.85 and 1.8 eV were estimated for nanotubes and nanoparticles, respectively, by extrapolating the linear part of the Tauc plot recorded for the films. The n-type Bi2S3thin films display a reasonable photoactivity under illumination and are thus promising candidates for photoelectrochemical applications. The photoelectrochemical characteristics recorded under AM 1.5 illumination indicated photocurrent density of 1.9 mA/cm2and 1.0 mA/cm2at 0.23 V versus Ag/AgCl/3 M KCl for the films deposited from chloroform and chloroform/toluene, respectively. The photocurrent is among the highest reported for any Bi2S3photoelectrode to date. Repeated illumination cycles show that the Bi2S3thin films display a reasonable photosensitivity and response indicating their potential to be used in photodetector and optoelectronic nanodevice applications. [ABSTRACT FROM AUTHOR]

α-Fe2O3thin film photoelectrodes were fabricated by aerosol-assisted chemical vapor deposition (AACVD) using a new hexanuclear iron precursor [Fe6(PhCOO)10(acac)2(O)2(OH)2]·3C7H8(1) (where PhCOO = benzoate and acac = 2,4-pentanedionate). The precursor (1) designed for AACVD has a low decomposition temperature and sufficient solubility in organic solvents and was synthesized by simple chemical techniques in high yield. It was characterized by melting point, FT-IR, X-ray crystallography, and thermogravimetry (TGA). The TGA analysis proved that complex (1) undergoes facile thermal decomposition at 475 °C to give iron oxide residue. In-house designed AACVD equipment was used to deposit highly crystalline thin films of α-Fe2O3on fluorine-doped SnO2coated glass substrates at 475 °C in a single step. The material properties were characterized by XRD, XPS, and Raman spectroscopy, and the results confirmed that films were highly crystalline α-Fe2O3and free from other phases of iron oxide. Further analysis of XRD data of the thin films proved the formation of crystalline hematite with an average diameter of 35 nm. X-ray photoelectron spectroscopy (XPS) confirmed that Fe is present only in the Fe3+oxidation state. Scanning electron microscopy (SEM) showed that the needle-like particles having length in the range of 100 to 160 nm with a diameter of 30−50 nm are sintered together to form a compact structure of the 80-nm-thick α-Fe2O3layer. Optical, electrical, and photoelectrochemical studies were conducted by UV−vis, electrochemical impedance spectroscopy, and steady-state current−voltage plots. The optical bandgap was estimated, and it is about 2.13 eV. The donor density of the α-Fe2O3was 2.914 × 1023m−3, and the flatband potential is approximately −0.86 V vs VAg/AgCl. The photoelectrochemical characteristics recorded under AM 1.5 illumination indicated that the photocurrent density of 600 μA cm−2at 1.23 V vs RHE, which is among the highest reported for an undoped α-Fe2O3photoelectrode to date. [ABSTRACT FROM AUTHOR]