This study articulates the fabricating of TiO2@g-C3N4 nanocomposite employing ultrasonic power starting with TiO2 and g-C3N4 as precursors. The fabricated nanostructures were characterized employing ...many techniques such as the X-ray diffraction (XRD), which revealed the mutual existence of g-C3N4 and anatase TiO2 phase peaks, and the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) that exposed the anchoring of TiO2 nanoparticles to the g-C3N4 layers. The coexistence of the composite constituent elements C, N, O, and Ti was verified by the energy dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS). The composite visible-light-driven photocatalytic performance was assessed using the indigo carmine (IC) dye, and the photocatalyst demonstrated outstanding performance. The photocatalytic process fitted the pseud-first-order kinetics with a rate that is seven times faster than bare TiO2. The photocatalysis improvement could be credited to the improved porosity, the low bandgap energy and efficient recombination inhibition of the photogenerated charge carriers at the heterojunction interfaces, and prevailing photo-prompted holes electrons. The mechanistic investigation revealed that the vital species considerably contributing to the dye photodegradation were peroxide radicals and holes as interpreted from scavenger trapping experiments. The study discloses the substantiation of a Z-scheme that facilitates the electron-hole pair separation for enhanced optical characteristics.
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•TiO2@g-C3N4 nanocomposite was ultrasonically fabricated using the precursors TiO2 and g-C3N4.•The anchoring of TiO2 and g-C3N4 was verified through the XPS and EDX techniques.•The nanocomposite has proficiently degraded the indigo carmine dye during a visible light driven process.•A Z-scheme model was suggested for the enhanced as confirmed through the ⁎O2−, h+ and ⁎OH involvement.
Herein, Y
2
O
3
@g-C
3
N
4
composite at different calcination temperatures was fabricated by ultrasonication method in the presence of methanol, and its photocatalytic competence was assessed by the ...photo-destruction of Congo red (CR). The XRD microstructural analysis manifested that the crystalize size estimated of Y
2
O
3
@g-C
3
N
4
changes from 16.17, 15.08, and 14.18 nm as the temperature is raised from 180 to 340
o
C. The SEM images confirmed the dispersion of Y
2
O
3
within the g-C
3
N
4
sheets whereas the EDX and XPS analysis quantized the elemental composition. The Y
2
O
3
@g-C
3
N
4
exhibited excellent photocatalytic performance following the pseudo-first-order kinetics due to charge carriers’ separation and the e
−
and
·
OH involvement through an S-scheme mechanism. The outcome of the study highlights the excellent photocatalytic activity of Y
2
O
3
@g-C
3
N
4
for dyes degradation under visible light.
Herewith we report a facile synthesis of zinc oxide doped with (5, 10, 15 and 20 wt%) titanium oxide nanocomposites in gelatin under ultra-sonication. The X-ray diffraction (XRD) data revealed the ...ZnO formation in addition to a rutile TiO
2
phase. The ZnO phase size decreased, while the rutile TiO
2
phase increased with a TiO
2
loading increment. The scanning electron microscopy (SEM) displayed a combination of spherical and hexagonal particles with 60–80 nm size distribution. The photocatalytic activity of the prepared nanostructures was assisted using Rhodamine B dye, where they showed enhanced photodegradation competence under visible light irradiation. The kinetics of photodegradation followed the first-order kinetics with the 20%wt sample showing the maximum activity. The mechanistic investigation revealed the dominance of
h
+
and ·O
2
−
species during the dye photodegradation. The results indicate the potential application of such gelatin-stabilized nanostructures for dye illumination from aqueous solutions under sunlight.
A mesoporous Zr-G-C3N4 nanomaterial was synthesized by a succinct-step ultrasonication technique and used for Cu2+ ion uptake in the aqueous phase. The adsorption of Cu2+ was examined by varying the ...operating parameters, including the initial metal concentration, contact time, and pH value. Zr-G-C3N4 nanosorbent displays graphitic carbon nitride (g-C3N4) and ZrO2 peaks with a crystalline size of ~14 nm, as determined by XRD analysis. The Zr-G-C3N4 sorbent demonstrated a BET-specific surface area of 95.685 m2/g and a pore volume of 2.16 × 10−7 m3·g−1. Batch mode tests revealed that removing Cu (II) ions by the mesoporous Zr-G-C3N4 was pH-dependent, with maximal removal achieved at pH = 5. The adsorptive Cu2+ ion process by the mesoporous nanomaterial surface is well described by the Langmuir isotherm and pseudo-second-order kinetics model. The maximum adsorption capacity of the nanocomposite was determined to be 2.262 mol·kg−1 for a contact time of 48 min. The results confirmed that the fabricated mesoporous Zr-G-C3N4 nanomaterial is effective and regenerable for removing Cu2+ and could be a potent adsorbent of heavy metals from aqueous systems.
The current study used La-Co
3
O
4
@g-C
3
N
4
nanostructures (LCoCN) produced by ultrasonic-and sol-gel processes to remove Co (II) ions from aqueous solutions. The successful development of the ...composite was verified by XRD which revealed both nitride and metal oxides phases. The EDX and XPS study confirmed its elemental composition from the blended precursors. LCoCN nanostructures demonstrated a minute pore volume of 0.72 cm
3
.g
−1
and a specific surface area of 33.677 m
2
/g. In addition, at a pH of 5.0, LCoCN demonstrated exceptional adsorption efficacy for Co (II). The Langmuir isotherm equilibrium was observed during the adsorption of Co (II), and it is estimated that the theoretical maximal adsorption capacity of Co (II) is 573.6 mg/g. The high precision with which the pseudo-first-order model describes the kinetic constant for Co ion adsorption onto LCoCN nanostructures is highlighted by its excellent fit to the experimental data. Thus, assessment of the adsorption potential of LCoCN in this work presented its satisfactory inherent potential with great adsorption aptitude to eliminate cobalt ions from aqueous solution demonstrating its practical applicability as an adsorbent.
In this study a ternary composite MgO–TiO
2
@g-C
3
N
4
was synthesized via a simplistic ultrasonic route and then it was characterized using various techniques. The development of tri-phased ...nanostructure was revealed by the X-ray diffraction (XRD) analysis. The X-ray photoelectron spectra (XPS) study confirmed the presence of the constituent elements while the bonding patterns were investigated by the Fourier transform infrared (FTIR). The as-acquired MgO–TiO
2
@g-C
3
N
4
heterojunction exhibited an optimal competence (94%) and enhanced photo-degradation rate constant towards the Alizarin Red S (ARS) dye in just 60 min under visible-light illumination. The heterostructured combined interfaces assembly of g-C
3
N
4
and MgO–TiO
2
NPs, have efficiently prompted the photo-excited charges separation, and blocked the recombination incidence. Henceforth, the prolonged lifetime has led to incessant generation of photoactive
−
species that ultimately upgraded the photo-degradation process. Furthermore, the fabricated hybrid photocatalysts showed superior recycling stability. A plausible photocatalytic reaction mechanism based on the S-scheme has been proposed. The advanced photocatalytic competence to degrade the AR dye under visible light irradiation makes MgO–TiO
2
@g-C
3
N
4
a favorable photocatalyst for the dye-containing wastewater treatment.
We report on synthesizing rare-earth yttrium oxide-doped ZnO nanoparticles through high-energy planetary milling approach. The impact of varying dopant content in the 3.0, 5.0 to 7.0 wt% range on ...microstructural, optical and electrical properties of ZnO nanoparticles has been successfully explored. The XRD data showed the existence of a hexagonal wurtzite ZnO phase along with Y
2
O
3
impurity peaks, and the SEM micrographs divulge the development of semi-spherical nanoparticles. The incorporation of Y
2
O
3
dopant in ZnO lattice has been supported by EDS, XPS and Raman analysis. The frequency and composition dependence of dielectric parameters was investigated and interpreted according to the Maxwell Wagner model. The data revealed non-monotonic dependence of the dielectric constant (
ε
r
), dielectric loss (tan
δ
) and AC conductivity and impedance of ZnO with varying dopant content. The variation of the shape of the impedance semicircles and the equivalent circuits between pure and doped ZnO samples prove increased grain boundary resistance due to Y
2
O
3
incorporation. The study reveals that Yttrium-doped ZnO nanostructures are possible potential candidates for application in electronic devices if the dopant’s content is controlled.
In this work, a sol–gel method has been employed to fabricate Cr-doped ZnO nanoparticles (NPs) in the presence of starch at different annealing temperatures. The obtained products were characterized ...by X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), and Fourier transforms infrared spectroscopy (FTIR). All samples were defined as hexagonal wurtzite ZnO with particle sizes equal to 26, 22, and 31 nm for pure ZnO, Cr-doped ZnO at 500 °C and 700 °C, respectively. The Cr-doped ZnO photocatalyst at 500 °C shifted the band gap energy of ZnO from 3.16 to 3.09 eV. The nanomaterials' photocatalytic activity was tested through the photodegradation of congo red (CR) under visible light illumination. The results demonstrated that the Cr-doped ZnO annealed at 500 °C is an excellent photocatalyst with enhanced degradation competence towards CR dye by virtue of its reduced size and lower band gap energy. The kinetics of the photodegradation fitted the pseudo-first-order model while the mechanistic investigations revealed the great impact of
h
+
and
·
OH on the degradation process. The starch-stabilized chromium-doped ZnO shows a high photocatalytic activity towards CR, indicating their possible environmental remediation application.
The photodegradation of Congo red dye by (Y
2
O
3
)
n
ZnO photocomposites was investigated through a sequence of experiments. X-ray diffraction analysis indicates nanocomposites' evolution having the ...ZnO wurtzite structure with increase in crystallite size and Y
2
O
3
phase segregation, as confirmed by the appearance and gradual growth of the Y
2
O
3
peak. Field emission scanning electron microscopy observations reveal irregular spherical morphology with increased agglomeration due to Y
2
O
3
loading. Diffuse reflectance spectra exhibit bandgap widening and red shift of the absorption edge with the doping process. Brunauer–Emmett–Teller analysis denotes improved porosity as manifested by the surface area, pore diameter, and pore volume increments after yttrium loading. Fortuitously, photocatalysts demonstrate excellent photodegradation rates for CR dye, reaching 93% at a higher rate of 43 × 10
–3
min
−1
. The photocomposite 1% Y
2
O
3
–ZnO exhibits a threefold enhancement in the visible photocatalytic process in an aqueous solution. The photocatalytic performance is discussed in detail concerning pH and oxygen species, which contribute to the photodegradation of CR dye. The results obtained in this study clearly highlight the superior performance (Y
2
O
3
)
n
ZnO as a highly efficient photocatalyst in the degradation of dyes in water.
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