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Calcium Copper Titanate Particles Based Energy Harvesting and Removal of Pharmaceutical Pollutants
(2025-05-13)
Kaja, Kushal Ruthvik
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Behera, Swayam Aryam
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Das, Bhagyashree
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Hajra, Sugato
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Panda, Swati
In this work, calcium copper titanate oxide (CaCu<inf>3</inf>Ti<inf>4</inf>O<inf>12</inf>, abbreviated as CCTO) was processed employing a solid-state reaction. The properties of CCTO were thoroughly characterized using various characterization tools. The CCTO particles layer and polytetrafluoroethylene (PTFE) acted as triboelectric layers, forming a contact and separation-based triboelectric nanogenerator (TENG). TENG, based on CCTO/PTFE, delivered an output of 74 V and 6 μA. TENG was utilized to harvest energy through various human activities, effectively charging capacitors, and was further attached to a pillow to monitor sleep. The study also evaluated the photocatalytic performance of CCTO for the degradation of doxycycline, achieving 87% efficiency within 45 minutes under visible light. The reaction pathway was thoroughly investigated, and catalyst reusability was examined. CCTO demonstrates potential as a dual-function material, serving both as a photocatalyst for environmental cleanup and as a triboelectric material for energy harvesting.
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Alkanolamine-Grafted and Copper-Doped Titanium Dioxide Nanosheets-Graphene Composite Heterostructure for CO2 Photoreduction
(2023-11-13)
Karawek, Apisit
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Kitjanukit, Nutkamol
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Neamsung, Wannisa
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Kinkaew, Chonlathon
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Phadungbut, Poomiwat
CO<inf>2</inf> photoreduction is an intriguing approach to carbon capture, utilization, and storage (CCUS). It relies on an effective photocatalyst to generate photoinduced electrons that incorporate carbon dioxide (CO<inf>2</inf>), yielding fuel products, e.g., methane, methanol, and ethanol. The heterostructure of titanium dioxide nanosheets (TNS) and graphene oxide (GO) is a sandwich-type composite consisting of two 2-dimensional nanostructures (2D-2D). It was demonstrated as an excellent candidate for CO<inf>2</inf> photoreduction due to its outstanding charge separation ability. This research studied the photoactivity of alkanolamine-grafted TNS and alkanolamine-grafted and copper-doped TNS/GO composites. In the first experiment, triethanolamine-grafted TNS (TEA-TNS) exhibited the best ability in CO<inf>2</inf> photoreduction compared to monoethanolamine- and diethanolamine-grafted TNS (MEA-TNS and DEA-TNS) due to the base-catalyzed hydration nature of CO<inf>2</inf>-TEA interactions. In the second experiment, we studied the photoactivity of four composites, including copper-doped TNS/GO (Cu-TNS/GO), TEA-[Cu-TNS/GO] (grafting TEA on Cu-TNS/GO), Cu-[TEA-TNS]/GO (doping Cu on TEA-TNS/GO), and TEA-Cu-TNS/GO (one-step hydrothermal synthesis with the Cu precursor, TEA, and GO). TEA-[Cu-TNS/GO] showed the best photoactivity since TEA was added last to the heterostructures, which benefited in avoiding side chelation reactions between TEA and Cu ions and ensuring TEA exposure to CO<inf>2</inf>
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Structural and Optical Properties of Mn-Incorporated BiVO4 Nanoparticles Synthesized by Sonochemical Process
(2022-01-01)
Wechprasit, Tirapat
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Kansaard, Thanaphon
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Bootchanont, Atipong
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Pecharapa, Wisanu
In this work, Mn-incorporated BiVO<inf>4</inf> nanoparticles with different Mn contents (0–5%) were synthesized by one-step sonochemical process. Structural phase of Mn-incorporated BiVO<inf>4</inf> nanoparticles was extensively carried out by X-ray diffraction technique. The XRD results show that the structural phase of BiVO<inf>4</inf> belongs to the monoclinic principal structure while the secondary phases of MnO, Mn<inf>2</inf>O<inf>3</inf>, and Mn<inf>3</inf>O<inf>4</inf> structures are noticed in Mn-loaded samples. Chemical bondings of Mn-incorporated BiVO<inf>4</inf> nanoparticles were characterized with Raman spectroscopy. Relevant chemical bondings confirm the existence of VO<inf>4</inf>3− tetrahedron and the V–O band by Raman spectra. Diffuse reflection spectroscopy and FE-SEM were employed to examine their optical and morphological properties, respectively. The results indicate that the incorporation of Mn can induce the red-shift of optical absorption edge in visible range, which can decrease the optical band gap of BiVO<inf>4</inf>. Morphology of all samples demonstrates the difference in shape of the compounds with the incorporation of Mn contents. Oxidation number and local structure of Mn-incorporated BiVO<inf>4</inf> nanoparticles were investigated by X-ray absorption spectroscopy. XAS results demonstrate that oxidation number of all elements correspond to Mn2+/Mn3+, Bi3+, and V5+ ions. The normalized Mn K-edge XANES spectra suggest that Mn atoms would not locate at the local site of Bi or V in BiVO<inf>4</inf> crystal because the specific feature of experimental spectra are inconsistent with simulated spectra, which is corresponded to XRD results indicating the formation of Mn-based oxide structures with various oxidation states.
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Piezoelectric enhanced photocatalytic properties of PVDF–ZnO/Cu nanofibers prepared by electrospinning technique
(2022-01-01)
Bootchanont, Atipong
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Porjai, Porramain
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Noonuruk, Russameeruk
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Wattanawikkam, Chakkaphan
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Pavasupree, Sorapong
Piezoelectric-assisted photocatalysis technology is one of the efficient ways to achieve enhancement in photocatalytic performance by facilitating the separation of photoinduced electron and holes via internal field initiated via piezoelectricity. Herein, bi-piezoelectric integrated effect was generated by the combination of piezoelectric semiconductor photocatalyst ZnO/Cu and piezoelectric polymer polyvinylidene fluoride (PVDF). Firstly, ZnO/Cu nanoparticles were prepared by facile co-precipitation method. Then, nanoparticles (at 10–30 wt%) were loaded in PVDF for fabricating nanofibers by electrospinning technique. All PVDF–ZnO/Cu nanofibers were characterized by XRD, FE-SEM, FTIR, XAS, and UV–Vis DRS. The structural study indicates that the β- and α-phase PVDF is observed in all the prepared nanofibers. XANES technique confirms the oxidation state of 2+ for Zn and Cu ions in both nanoparticles and nanofibers. Furthermore, under the synergy action of ultrasonic and visible light irradiation, PVDF–ZnO/Cu nanofibers exhibit superior piezo-photocatalytic degradation of rhodamine B dye when compared with single light or mechanical excitation. Effects of ZnO/Cu concentration on optical, piezoelectric, and photocatalytic properties are discussed.
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CeO2/CuO/TiO2heterojunction photocatalysts for conversion of CO2to ethanol
(2021-09-10)
Seeharaj, Panpailin
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Vittayakorn, Naratip
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Morris, John
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Kim-Lohsoontorn, Pattaraporn
An attempt to reduce CO2 emissions has led to the development of CeO2/CuO/TiO2 heterojunction photocatalysts for photoconversion of CO2 to useful products, e.g. ethanol. Composite photocatalysts were simply prepared by mixing TiO2 (P25) with different mass ratios of CeO2 (1 wt%) and CuO (2 or 3 wt%) by ball milling. The prepared photocatalysts had uniformly distributed CeO2 and CuO phases, throughout the TiO2 phase. The integration of CeO2 and CuO into TiO2 at 1 wt% CeO2 and 3 wt% CuO produced a composite, with a reduced band gap of 2.88 eV, allowing absorption of lower energy light and a lower electron-hole recombination rate. The 1%CeO2/3%CuO/TiO2 photocatalysts yielded ethanol at 30.5 μmol gcat-1 h-1, almost three times higher than the yield from pure TiO2. This improved CO2 conversion efficiency was due to contributions from properties of both additives: CeO2 increased light absorption, while CuO acted as an electron trap and enhanced CO2 adsorption. In addition, the heterojunction at the interfaces facilitated the photogenerated charge separation, which, in turn, increased the charge participation in the catalyzed conversion reactions.
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Characterization of BiVO4 nanoparticles prepared by sonochemical process
(2019-11-18)
Kansaard, Thanaphon
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Pecharapa, Wisanu
Nowadays, environment highly encounters various pollutants including toxic gases, organic volatiles and water pollutant. Many scientists have taken the effort to reduce or eliminate pollutant using photocatalytic materials. Due to good ferroelectric property in ferroelastic crystal as a result of the reduction in symmetry between the paraelastic and ferroelastic phases, it makes bismuth vanadate (BiVO<inf>4</inf>) one of attractive ferroelectric materials. In addition, BiVO<inf>4</inf> with low optical band gap could be activated by visible light illumination so that it would be a potential candidate as a visible light driven photocatalyst. This work was carried out to synthesize BiVO<inf>4</inf> nanoparticles by simple but effective method via sonochemical process through chemical route assisted by ultrasonic irradiation. The crystalline structure and surface morphologies of the synthesized products were observed by X-ray diffraction technique and Scanning Electron Microscope, respectively. Raman spectroscopy and Fourier Transform Infrared spectroscopy were used to approve the BiVO<inf>4</inf> chemical bonding and relevant crystalline formation. Photocatalytic activity was studied by mean of the degradation of organic dye assigned as organic compound under visible light irradiation.

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