Modulating water oxidation kinetics utilizing h-BN quantum dots as an efficient hole extractor on fluorine doped hematite photoanode

Sahu, Tushar Kanta; Mohanta, M K; Qureshi, Mohammad

doi:10.1016/j.jpowsour.2019.227341

Cited by 32 publications

(11 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The as-grown BNQDs have an average lateral size of 3 nm, and an average thickness of 0.7 nm. A similar aqueous synthesis method of BNQDs was reported by others [71][72][73]. Later, Liu et al [74] used the microwave method to synthesize BNQDs with a QY 10.31% by dissolving boric acid and melamine in ultra-pure water and placing them in a microwave oven set at a frequency of 1000 Hz for 70 min at 120 • C. The authors also reported for the synthesis of sulfur S-regulated BNQDs using the same microwave method and same precursors (boric acid and melamine) [75].…”

Section: Hydrothermal Methodsmentioning

confidence: 78%

“…Moreover, the incident photon to current conversion efficiency (IPCE) using the modified photoanode has reached 32%, which is 2.1 times higher than that when pristine WO 3 anode was used. On the other hand, Sahu et al reported superior PEC performance in water splitting using BNQDs incorporated over fluorine-doped hematite (F-Fe 2 O 3 ) nanorods [73]. 1-D hematite nanorod arrays quickly transferred electrons to the FTO substrate, while BNQDs acted as the efficient hole extractors that enhanced charge separation on the hematite surface by decreasing the hole trapping probability.…”

Section: Photocatalystmentioning

confidence: 99%

See 1 more Smart Citation

A Review on van der Waals Boron Nitride Quantum Dots

Acharya

Sharma

Liu

et al. 2021

View full text Add to dashboard Cite

Boron nitride quantum dots (BNQDs) have gained increasing attention for their versatile fluorescent, optoelectronic, chemical, and biochemical properties. During the past few years, significant progress has been demonstrated, started from theoretical modeling to actual application. Many interesting properties and applications have been reported, such as excitation-dependent emission (and, in some cases, non-excitation dependent), chemical functionalization, bioimaging, phototherapy, photocatalysis, chemical, and biological sensing. An overview of this early-stage research development of BNQDs is presented in this article. We have prepared un-bias assessments on various synthesis methods, property analysis, and applications of BNQDs here, and provided our perspective on the development of these emerging nanomaterials for years to come.

show abstract

Section: Hydrothermal Methodsmentioning

confidence: 78%

Section: Photocatalystmentioning

confidence: 99%

A Review on van der Waals Boron Nitride Quantum Dots

Acharya

Sharma

Liu

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Figure b exhibits the Nyquist plots of the bare hematite NRs and the LIPR-24 measured under illumination at 1.23 V versus RHE. The Nyquist plots are composed of two semicircles, implying that each PEC cell can be regarded as an electric circuit [equivalent circuit (EC)] comprising two parallel resistor–capacitor circuits, as shown in Figure c. − The semicircle obtained at relatively high frequencies is related to the charge transport at the depletion layer and another semicircle obtained at low frequencies is assigned to the charge-transfer process at the hematite/electrolyte interface . The EC emphasizes the role of the surface states at the hematite/electrolyte interface as a carrier recombination center and is composed of three resistors and two capacitors, namely, series resistance ( R s ), charge-trapping resistance ( R trap ), surface-state resistance ( R ss ), bulk capacitance ( C dl ), and surface-state capacitance ( C ss ). , The values of the resistors and capacitors were estimated by fitting the Nyquist plots to the EC.…”

Section: Resultsmentioning

confidence: 99%

Laser-Induced Photoreduction for Selective Tuning of the Oxidation State and Crystal Structure of Hematite Nanorods

et al. 2021

View full text Add to dashboard Cite

The laser-induced photoreduction process is proposed to obtain patterned magnetite (Fe3O4) nanorod (NR) arrays or the oxygen vacancy (OV) engineering of the hematite (α-Fe2O3) NRs. A continuous-wave laser beam, with a wavelength of 532 nm, is focused on the hematite NRs that are in contact with a liquid reducing agent to provide the thermal energy for triggering the reduction reaction. The path of the laser beam can be controlled through computer software, enabling the reduction reaction to occur in the arbitrary desired area. At lower laser powers than that at which the direct transformation of hematite into magnetite occurs, hematite NRs with a high concentration of OV are produced. The high OV concentration contributes to improving the electrical conductivity of the hematite NRs by increasing the donor density. The OV-abundant hematite NR array is applied to a photoanode in a photoelectrochemical (PEC) water-splitting cell. It exhibits an enhanced PEC performance due to its donor density being higher in comparison with the bare hematite NRs.

show abstract

“…However, surface redox reactions cannot rely on the inert passivated layer, and a cocatalyst on the passivation layer is generally used as an active site to promote redox reactions. The general rule of a cocatalyst can be referred to as the electrocatalyst, and a variety of metal-based materials were developed for WRR − and WOR. − Recently, metal-free materials with abundant functional groups on the surface have emerged as cocatalysts − with tunable surface properties, enabling the further regulation of redox reactions.…”

Section: Rational Design Of Photoelectrodes For Pec Water Splittingmentioning

confidence: 99%

Roles of Metal-Free Materials in Photoelectrodes for Water Splitting

Wang

Fang

et al. 2021

Acc. Mater. Res.

View full text Add to dashboard Cite

Metrics & MoreArticle Recommendations * sı Supporting Information CONSPECTUS: Photoelectrochemical (PEC) water splitting is an appealing approach to the hydrogen evolution reaction since it converts sunlight in the form of hydrogen fuel, which has the potential to revolutionize the fossil fuel-based energy systems of the modern society. In the last half century, progress has been made with respect to the material, synthesis, and system. Recent developments of multilayered photoelectrodes have made a breakthrough to improve the sunlight conversion efficiency and strengthen the physiochemical stability. The exploration of new materials for the functional layers of photoelectrodes offers a new opportunity for practical application. Among the emerging materials, metal-free species have shown superior properties, such as high stability, sustainability, and renewability. With respect to inorganic materials, their physiochemical properties can be readily regulated, including thermodynamics and kinetics, and thus increasing attention has been devoted. In this Account, the functional components of a photoelectrodes are specified, namely conductive layers for charge separation and transfer, photocatalytic layers for light absorption, passivation layers for protection of the electrode, and cocatalysts for the acceleration of the surface reaction. We have focused metal-free materials for the functional layers, including the (1) carbon cloth and carbon quantum dots (CQDs) for the conductive layer, 2) polymeric carbon nitrides (PCNs), carbon doped boron nitride, and covalent organic frameworks for photocatalytic layers, and (3) CQDs and black phosphorene for cocatalysts. We aim to identify the relationship between the function of the metal-free materials and the performance of the water splitting reaction. With respect to the outlook, discussions have been presented for the further development of metal-free materials to improve the performance of each functional layer. Despite the fact that the use of metal-free materials for PEC water splitting is still in its infancy, this Account not only provides new thoughts and opportunities to pursue an improved performance for the water-splitting reaction but also stimulates advanced applications by using metal-free PEC systems.

show abstract

Modulating water oxidation kinetics utilizing h-BN quantum dots as an efficient hole extractor on fluorine doped hematite photoanode

Cited by 32 publications

References 42 publications

A Review on van der Waals Boron Nitride Quantum Dots

A Review on van der Waals Boron Nitride Quantum Dots

Laser-Induced Photoreduction for Selective Tuning of the Oxidation State and Crystal Structure of Hematite Nanorods

Roles of Metal-Free Materials in Photoelectrodes for Water Splitting

Contact Info

Product

Resources

About