TY - JOUR
T1 - Optical and photocatalytic properties of biomimetic cauliflowered Ca2Mn3O8–CaO composite thin films
AU - Munawar, Khadija
AU - Mansoor, Muhammad Adil
AU - McKee, Vickie
AU - Zaharinie, Tuan
AU - Mohd Zubir, Mohd Nashrul
AU - Aspanut, Zarina
AU - Yusof, Farazila Binti
AU - Mazhar, Muhammad
PY - 2020/10
Y1 - 2020/10
N2 - Inspired from the μ-oxido CaMn4 cluster unit present in the photosystem-II of plant cells, various manganese-based materials, particularly calcium-manganese oxides, have been investigated by the researchers as a new class of catalysts. Herein, we report the synthesis of single source heterobimetallic complex {[CaMn(OAc)(TFA)3(THF)(H2O)2].3THF}n (where OAc = acetate, TFA = trifluoroacetate and THF = tetrahydrofuran) for the deposition of thin films of Ca2Mn3O8–CaO composite on fluorine doped tin oxide (FTO) coated glass substrates at deposition temperatures of 450–550 °C via the aerosol assisted chemical vapour deposition (AACVD) method. The complex was characterized by melting point, microanalysis, proton nuclear magnetic resonance (1H NMR), Fourier transformed infra-red (FT-IR) spectroscopy, thermogravimetry (TGA) and single crystal X-ray diffraction. The deposited thin films were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDX) and field emission scanning electron microscopy (FESEM) which confirmed the growth of Ca2Mn3O8–CaO composite with high purity and precise stoichiometry. The optical characterization gave direct band gap energies of 2.74, 2.68 and 2.77 eV for the Ca2Mn3O8–CaO thin films deposited at 450, 500 and 550 °C, respectively. Furthermore, photoelectrochemical studies revealed that the thin film deposited at 500 °C showed the photocurrent of 3.75 mA cm−2 at +0.8 V vs. SCE with 1.64% photo-conversion efficiency and 310 Ω Rct value, upon illumination with a 150 W (100 mW cm−2) halogen lamp. The improved photocatalytic activity of Ca2Mn3O8–CaO composite was due to the increased photo absorption ability, elevated surface area, and more efficient electron/hole transfer. In addition, this work provides an insight to design the growth of visible light active calcium-manganese based photocatalyst materials for solar energy utilization.
AB - Inspired from the μ-oxido CaMn4 cluster unit present in the photosystem-II of plant cells, various manganese-based materials, particularly calcium-manganese oxides, have been investigated by the researchers as a new class of catalysts. Herein, we report the synthesis of single source heterobimetallic complex {[CaMn(OAc)(TFA)3(THF)(H2O)2].3THF}n (where OAc = acetate, TFA = trifluoroacetate and THF = tetrahydrofuran) for the deposition of thin films of Ca2Mn3O8–CaO composite on fluorine doped tin oxide (FTO) coated glass substrates at deposition temperatures of 450–550 °C via the aerosol assisted chemical vapour deposition (AACVD) method. The complex was characterized by melting point, microanalysis, proton nuclear magnetic resonance (1H NMR), Fourier transformed infra-red (FT-IR) spectroscopy, thermogravimetry (TGA) and single crystal X-ray diffraction. The deposited thin films were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDX) and field emission scanning electron microscopy (FESEM) which confirmed the growth of Ca2Mn3O8–CaO composite with high purity and precise stoichiometry. The optical characterization gave direct band gap energies of 2.74, 2.68 and 2.77 eV for the Ca2Mn3O8–CaO thin films deposited at 450, 500 and 550 °C, respectively. Furthermore, photoelectrochemical studies revealed that the thin film deposited at 500 °C showed the photocurrent of 3.75 mA cm−2 at +0.8 V vs. SCE with 1.64% photo-conversion efficiency and 310 Ω Rct value, upon illumination with a 150 W (100 mW cm−2) halogen lamp. The improved photocatalytic activity of Ca2Mn3O8–CaO composite was due to the increased photo absorption ability, elevated surface area, and more efficient electron/hole transfer. In addition, this work provides an insight to design the growth of visible light active calcium-manganese based photocatalyst materials for solar energy utilization.
KW - AACVD
KW - Band gap
KW - Calcium–manganese molecular precursor
KW - Optical properties
KW - Photoelectrochemical water splitting
KW - Thin films
U2 - 10.1016/j.jssc.2020.121552
DO - 10.1016/j.jssc.2020.121552
M3 - Journal article
AN - SCOPUS:85087760781
SN - 0022-4596
VL - 290
JO - Journal of Solid State Chemistry
JF - Journal of Solid State Chemistry
M1 - 121552
ER -