Water splitting behavior of copper-cerium oxide nanorods and nanocubes using hydrazine as a scavenging agent

Clavijo-Chaparro, S.L.; Hernández-Gordillo, Agileo; Camposeco-Solís, Roberto; Rodríguez-González, Vicente

doi:10.1016/j.molcata.2016.06.011

Cited by 14 publications

(9 citation statements)

References 33 publications

(43 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, binding energies of 8.14 and 6.5 eV were reported for electrons at the valence band maximum of stoichiometric 12 and nonstoichiometric CeO 2 . 11,49,50 These values agree with the reported ionization potentials (6.5 eV vs vacuum and 9.0 eV vs vacuum), which vary as a function of Ce 3+ content for CeO 2 films. 17,45 Importantly, the energy level alignment in Figure 1 predicts that the photoexcited electrons in C-343 can be transferred into trap states below the Ce 5d band edge.…”

Section: ■ Results and Discussionsupporting

confidence: 89%

“…Our proposed band edges for CeO 2 , as shown in Figure , differ slightly from those in some reports but generally fall within the range of literature values. For example, binding energies of 8.14 and 6.5 eV were reported for electrons at the valence band maximum of stoichiometric and nonstoichiometric CeO 2 . ,, These values agree with the reported ionization potentials (6.5 eV vs vacuum and 9.0 eV vs vacuum), which vary as a function of Ce 3+ content for CeO 2 films. , Importantly, the energy level alignment in Figure predicts that the photoexcited electrons in C-343 can be transferred into trap states below the Ce 5d band edge. Our spectroscopic results (see below) strongly support this conclusion and confirm that the energy level diagram in Figure is reasonable.…”

Section: Resultssupporting

confidence: 78%

See 1 more Smart Citation

Ultrafast Electron Injection and Recombination Dynamics of Coumarin 343-Sensitized Cerium Oxide Nanoparticles

et al. 2021

View full text Add to dashboard Cite

Dye-sensitized electron injection into cerium oxide (CeO 2 ) nanoparticles is studied using femtosecond transient absorption spectroscopy. Following the 430 nm photoexcitation of coumarin 343 molecules adsorbed on CeO 2 nanoparticles, mid-infrared (mid-IR) transient absorption signals appear within 500 fs. Mid-IR signals are assigned to electrons injected into broadly distributed trap or defect states found roughly midway between the Ce 5d conduction band edge and the bottom of the empty band of Ce 4f states. These states are proposed to have Ce 5d character. In contrast, mid-IR signals are not observed when electrons in bare CeO 2 nanoparticles are promoted from the valence band to the band built from Ce 4f orbitals by UV excitation. Transient absorption signals from the oxidized dye rise within 300 fs and decay somewhat more slowly than the mid-IR signals, suggesting that electron relaxation occurs within CeO 2 in competition with back-electron transfer to the oxidized dye. These results reveal elementary events important for understanding photocatalysis using CeO 2 nanoparticles. Article pubs.acs.org/JPCC

show abstract

Section: ■ Results and Discussionsupporting

confidence: 89%

Section: Resultssupporting

confidence: 78%

Ultrafast Electron Injection and Recombination Dynamics of Coumarin 343-Sensitized Cerium Oxide Nanoparticles

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The size is similar for all the Ce loads; likewise, the morphology did not change. However, in the NiH-Ce10 sample, some short CeO 2 nanorods can be distinguished (figures 2(c), (d)) [30]. As a detrimental effect of Ce excess, some Ni(OH) 2 layers are not completely exfoliated (see the size distribution data in figures S1-S3 of the supplementary The XRD results corroborate this fact, where Ce allows the exfoliation of Ni layers in a hydrothermal environment, and the doping decreases the size of the exfoliated nanoplates.…”

Section: Resultsmentioning

confidence: 99%

“…The HAADF image shows the transparency of the layers, confirming exfoliation, and the in-set EDS shows the composition. In figure 3(d), β-Ni(OH) 2 with 10% of the Ce load presents both morphologies: exfoliated hexagonal plates and short nanorod-like CeO 2 [30].…”

Section: Resultsmentioning

confidence: 99%

Cerium-doped β-Ni(OH)₂ hexagon nanosheets: an effective photocatalyst for the degradation of the emerging water pollutant, naproxen

2018

View full text Add to dashboard Cite

Nickel hydroxide β-Ni(OH) hexagonal nanosheets were synthetized via a hydrothermal exfoliation process. The practical microwave-assisted hydrothermal method facilitated obtaining layered nickel 3D nanoplates with cerium functionalization in 5 h. The as-produced nanostructures were characterized by XRD, XPS, FESEM, FTIR, PL, UV-vis, and BET techniques. The hydroxilated structures are nano-thick hexagonal plates with sides 28 nm in length and an average thickness of 5 nm. UV and PL irradiation was used to study the photoactive properties in the degradation of a pharmaceutical emerging pollutant, naproxen. UV-vis spectroscopy and high-performance liquid chromatography monitoring indicated that the Ni(OH)-Ce nanostructures are an effective photocatalyst for naproxen degradation, including 40% mineralization of this highly recalcitrant drug. The photocatalyst showed stability for two consecutive cycles, preserving its photoactive and structural characteristics. Ce-doped nanoplates and surface functionalized Ce act as charge separators and scavenging agents for the enhanced photodegradation of naproxen.

show abstract

“…In addition, the 2.5 Cu/Ti and 5.0 Cu/Ti samples thermally treated at 500 • C show a well-defined reduction peak that starts at 160 and ends at 210 • C; this peak is also related to the Cu 2+ → Cu + reduction. The shoulders observed for the 5.0 Cu/Ti 500 sample at 225 and 275 • C are associated with the continuous reduction from Cu + to Cu 0 species [21].…”

Section: Temperature Programmed Reductionmentioning

confidence: 86%

Wastewater Contaminated with Hydrazine as Scavenger Agent for Hydrogen Production by Cu/Ti Nanostructures

2021

View full text Add to dashboard Cite

Cu/Ti photocatalysts were prepared by the sol-gel process with different copper loadings (1.0, 2.5, and 5.0 wt.%) and then thermally treated at several calcination temperatures from 400 to 600 °C. The materials were characterized by X-ray diffraction (XRD), N2 physisorption, Scanning Electronic Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS), Ultraviolet-visible-Diffuse Reflection Spectroscopy, Ultraviolet-visible spectroscopy as a function of the temperature, (Temperature Programmed Reduction) TPR-chemisorption, XPS (X-ray Photoelectron Spectroscopy) and OH determination through DRIFTS (Diffuse reflectance infrared Fourier transform spectroscopy). The Cu/Ti photocatalysts were evaluated for the photocatalytic production of hydrogen using hydrazine as scavenging agent. Moreover, a detailed study of the Cu1+/Cu2+ ratio and the corresponding formation of copper oxide was carried out to understand the correlation between the copper species and the photocatalytic activity. Simultaneously, the OH groups on the TiO2 surface also show insights into the behavior of these materials during the photocatalytic reaction. Despite the low hydrazine concentration (20 mM), the 1.0 (wt.%) Cu/Ti 500 photocatalyst enhanced the hydrogen production three and two times more than photolysis and bare TiO2, respectively. The 1.0 Cu/Ti 500 photocatalyst displayed outstanding stability for at least three continuous cycles of 8 h each, preserving the hydrogen production. The novel ability shown in this work represents an alternative to reduce the hydrazine residues in wastewater to transform it into a hydrogen-producing energy source and must be extended to other reductive pollutants found in wastewater.

show abstract

Water splitting behavior of copper-cerium oxide nanorods and nanocubes using hydrazine as a scavenging agent

Cited by 14 publications

References 33 publications

Ultrafast Electron Injection and Recombination Dynamics of Coumarin 343-Sensitized Cerium Oxide Nanoparticles

Ultrafast Electron Injection and Recombination Dynamics of Coumarin 343-Sensitized Cerium Oxide Nanoparticles

Cerium-doped β-Ni(OH)₂ hexagon nanosheets: an effective photocatalyst for the degradation of the emerging water pollutant, naproxen

Wastewater Contaminated with Hydrazine as Scavenger Agent for Hydrogen Production by Cu/Ti Nanostructures

Contact Info

Product

Resources

About

Water splitting behavior of copper-cerium oxide nanorods and nanocubes using hydrazine as a scavenging agent

Cited by 14 publications

References 33 publications

Ultrafast Electron Injection and Recombination Dynamics of Coumarin 343-Sensitized Cerium Oxide Nanoparticles

Ultrafast Electron Injection and Recombination Dynamics of Coumarin 343-Sensitized Cerium Oxide Nanoparticles

Cerium-doped β-Ni(OH)2 hexagon nanosheets: an effective photocatalyst for the degradation of the emerging water pollutant, naproxen

Wastewater Contaminated with Hydrazine as Scavenger Agent for Hydrogen Production by Cu/Ti Nanostructures

Contact Info

Product

Resources

About

Cerium-doped β-Ni(OH)₂ hexagon nanosheets: an effective photocatalyst for the degradation of the emerging water pollutant, naproxen