Visible‐Light‐Active Photocatalysis: Nanostructured Catalyst Design, Mechanisms, and Applications

Kumar, R. Vasant; Coto, Michael

doi:10.1002/9783527808175.ch18

Cited by 5 publications

(4 citation statements)

References 66 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…15−20 The major setback is the very fast recombination of photo excitons pair, which is addressed by utilizing highly conductive metals such as Pt, Pd, Rh, Au, and so forth. 1,21,22 Despite solving the recombination issue, it is not economically viable. Hence, many studies were carried out in search of alternatives for noble metals.…”

Section: Introductionmentioning

confidence: 99%

“…Most photocatalysts suffer from fast photo exciton recombination, effective light absorption, and stability. To overcome these drawbacks, many researchers are working on fruitful ways such as heterojunction with other semiconductors to increase their efficacy and maintain good stability. − The major setback is the very fast recombination of photo excitons pair, which is addressed by utilizing highly conductive metals such as Pt, Pd, Rh, Au, and so forth. ,, Despite solving the recombination issue, it is not economically viable. Hence, many studies were carried out in search of alternatives for noble metals.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

S-Scheme TiO₂/CuNb₂O₆ Nanocomposite Photocatalyst with Enhanced H₂ Evolution Activity from Aqueous Glycerol Solution

Ravi

Sreedhar

Noh

2023

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

Steering of photoexcitons via interface engineering of semiconductor photocatalysts is key to achieving a stable and efficient photocatalyst for continuous hydrogen production. Among them, the development of 1D nanostructures with several advantageous properties such as wide surface area, effective light harvesting, and increased electron moving kinetics has received special attention. In this work, 1D titania nanobars were successfully synthesized via the methanol-assisted solvothermal method, in which alcohol formed hydrogen bonds with nuclei, which consequently encouraged the growth of nanobars. Following this, the titania nanobars were integrated with solvothermally synthesized monoclinic CuNb 2 O 6 nanoparticles. TEM analysis revealed the formation of TiO 2 nanobars and their uniform interaction with CuNb 2 O 6 nanoparticles. A S-scheme heterojunction is formed at the interface of TiO 2 nanobars and CuNb 2 O 6 nanoparticles. 1D morphology of titania and CuNb 2 O 6 plays a key role in light absorption and boosts the photocatalytic activity by promoting the separation and transfer of photoexcited charge carriers. The electrons at the TiO 2 conduction band and holes at the valance band of CuNb 2 O 6 facilitated recombination at the heterojunction. The remaining electrons at the conduction band of CuNb 2 O 6 and holes at the valance band of TiO 2 tend to participate in redox reactions at their terminals. As the loading of CuNb 2 O 6 increases, the rate of activity initially increases and then decreases, which is consistent with the trend for light penetration-dependent photocatalytic hydrogen evolution. The band edge potentials of TiO 2 and CuNb 2 O 6 were also revealed using VB-XPS and UPS analysis. In addition to catalytic stability, the effect of glycerol concentration, catalyst loading, time on stream, recyclability, and parametric analysis which aided in the discovery of ideal experimental conditions is revealed. Under optimal conditions, the photocatalyst showed an enhanced rate of H 2 generation (146 mmol h −1 g cat −1) under simulated solar light irradiation. The solar to H 2 conversion efficacy is also discussed with comparison.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

S-Scheme TiO₂/CuNb₂O₆ Nanocomposite Photocatalyst with Enhanced H₂ Evolution Activity from Aqueous Glycerol Solution

Ravi

Sreedhar

Noh

2023

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

show abstract

“…The chronicle of semiconductors as a photocatalyst, which can be used for water splitting, had been proven by Fujishima and Honda during the 20th century, and it paved the way for exploration of various semiconductor materials for photocatalytic water splitting. − Generally, the most important steps which affect a photocatalyst are light absorption, photoexciton generation, charge separation, and their transfer to the respective redox reaction. ,− In this scenario, a motley of narrow and wide band gap semiconductors such as metal sulfides (ZnCdS, CuInS 2 , Cu 2 S, ZnS, and CdS), − metal oxides (BiOCl, TiO 2 , SrTiO 3 , ZnO, NiO, CuO, BiVO 4 , etc. ), − oxynitrides, metal-free semiconductors, and oxysulfides were explored for photocatalytic activity. − In spite of many innovations, some hindrances appeared to be indispensable.…”

Section: Introductionmentioning

confidence: 99%

Temperature-Driven Morphology Control on CdSe Nanofractals and Its Influence over the Augmented Rate of H₂ Evolution: Charge Separation via the S-Scheme Mechanism with Incorporated Cu₃P

Ravi

Kumaravel

Subramanian

et al. 2021

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

The thermodynamically controlled synthesis of dendritic fractals and nanorods via the hydrothermal reaction has been described, and their extensive photocatalytic hydrogen production properties under simulated solar light have been demonstrated. The long-range and short-range growth of CdSe monomers has been controlled by varying the reaction temperature from 100 to 200 °C. Changes in the physical and optical properties of prepared dendrites and nanorods have been evidently proven with microscopic analysis, diffuse reflectance spectroscopy, and BET analysis. A high-surface area CdSe dendritic fractal has been incorporated with bifunctional Cu3P nanoparticles that resulted in a highly efficient photocatalyst construction. Consequently, a pivotal upswing in the photocatalytic performance of CdSe was found by the formation of the S-scheme heterojunction with Cu3P. The unique properties of transition-metal phosphides kept them as a highly capable co-catalyst to replace precious metals. The physicochemical properties of the prepared materials were characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy. The key challenge in the photocatalytic water splitting process is to develop an efficient photocatalyst not only with high chemical and photochemical stability but also with strong solar light absorption and effective charge separation ability. The co-catalyst Cu3P gives an effective path as it forms the S-scheme heterojunction with CdSe dendritic fractals. This enhances photoactivity and stability of the prepared composite. The composite made of CdSe and Cu3P showed a better rate of H2 production (92.1 mmol h–1 gcat –1) with 4% visible light to hydrogen conversion efficacy. The effects of Cu3P growth, size, and morphology of CdSe on the photocatalytic performance have been studied. Based on the material characterization and photocatalytic activity results, the working mechanism is also proposed.

show abstract

“…The fast photo‐generated (electron–hole pair) recombination rate of TiO 2 ‐P25 could also further limit its use. This problem can be resolved by matching the band levels of the semiconductor in a way that causes the photo‐generated electrons to cascade into the low‐lying conduction bands, whereas the holes move to the higher energy levels 48,49 . Thus, the electrons will be accumulated on one semiconductor, and at the same time, the holes will be confined in the other one.…”

Section: Introductionmentioning

confidence: 99%

The first report of deep eutectic solvent (DES) nano‐photocatalyst (n‐TiO₂‐P25@TDI@DES (urea: ZnCl₂)) and its application on selective oxidation of benzyl alcohols to benzaldehydes

Taghavi

Amoozadeh

Nemati

2020

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

BACKGROUNDDeep eutectic solvents (DESs) are prepared by mixing solid organic precursors to form a liquid driven from strong hydrogen‐bond interactions. The physical and chemical properties of these compounds have been widely investigated, and it has been shown that they are benign media for biotransformations, organicsynthesis, biodieselpreparation, and a sustainable media for nanoscale and functional materials.RESULTSThis study is the first report on the synthesis of n‐TiO2‐P25@TDI@DES (urea: ZnCl2) with photo catalytic activity. This nano photocatalyst was obtained through covalent grafting of TiO2‐P25 nanoparticles to an inexpensive and highly reactive linker (2,4‐toluene diisocyanate). The presented nano photocatalyst has been employed as a covalently grafted Lewis acidic deep eutectic solvent to oxidize various primary benzyl alcohols to their corresponding carbonyl compounds by sodium nitrate as oxidant, under visible light exposure.CONCLUSIONThis highly efficient nanocatalyst was investigated by various characterization techniques including fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy equipped with energy‐dispersive X‐ray spectroscopy (SEM with EDX), and elemental analysis. Owing to its enhanced catalytic activity, thermal stability, and environmentally friendly nature, the present method can be regarded as an attractive green chemistry approach. © 2020 Society of Chemical Industry (SCI)

show abstract

Visible‐Light‐Active Photocatalysis: Nanostructured Catalyst Design, Mechanisms, and Applications

Cited by 5 publications

References 66 publications

S-Scheme TiO₂/CuNb₂O₆ Nanocomposite Photocatalyst with Enhanced H₂ Evolution Activity from Aqueous Glycerol Solution

S-Scheme TiO₂/CuNb₂O₆ Nanocomposite Photocatalyst with Enhanced H₂ Evolution Activity from Aqueous Glycerol Solution

Temperature-Driven Morphology Control on CdSe Nanofractals and Its Influence over the Augmented Rate of H₂ Evolution: Charge Separation via the S-Scheme Mechanism with Incorporated Cu₃P

The first report of deep eutectic solvent (DES) nano‐photocatalyst (n‐TiO₂‐P25@TDI@DES (urea: ZnCl₂)) and its application on selective oxidation of benzyl alcohols to benzaldehydes

Contact Info

Product

Resources

About

Visible‐Light‐Active Photocatalysis: Nanostructured Catalyst Design, Mechanisms, and Applications

Cited by 5 publications

References 66 publications

S-Scheme TiO2/CuNb2O6 Nanocomposite Photocatalyst with Enhanced H2 Evolution Activity from Aqueous Glycerol Solution

S-Scheme TiO2/CuNb2O6 Nanocomposite Photocatalyst with Enhanced H2 Evolution Activity from Aqueous Glycerol Solution

Temperature-Driven Morphology Control on CdSe Nanofractals and Its Influence over the Augmented Rate of H2 Evolution: Charge Separation via the S-Scheme Mechanism with Incorporated Cu3P

The first report of deep eutectic solvent (DES) nano‐photocatalyst (n‐TiO2‐P25@TDI@DES (urea: ZnCl2)) and its application on selective oxidation of benzyl alcohols to benzaldehydes

Contact Info

Product

Resources

About

S-Scheme TiO₂/CuNb₂O₆ Nanocomposite Photocatalyst with Enhanced H₂ Evolution Activity from Aqueous Glycerol Solution

S-Scheme TiO₂/CuNb₂O₆ Nanocomposite Photocatalyst with Enhanced H₂ Evolution Activity from Aqueous Glycerol Solution

Temperature-Driven Morphology Control on CdSe Nanofractals and Its Influence over the Augmented Rate of H₂ Evolution: Charge Separation via the S-Scheme Mechanism with Incorporated Cu₃P

The first report of deep eutectic solvent (DES) nano‐photocatalyst (n‐TiO₂‐P25@TDI@DES (urea: ZnCl₂)) and its application on selective oxidation of benzyl alcohols to benzaldehydes