Oxygen Vacancies and Ti3+ In-Gap Defects Dictate Photocatalytic H2 Generation in BaTiO3 DOI
Sujana Chandrappa, P. S. Sankara Rama Krishnan, Stephen Nagaraju Myakala

et al.

ACS Applied Energy Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 21, 2024

Ubiquitous oxygen vacancies and mutually correlated Ti3+ defects in ABO3-type perovskite titanate, such as BaTiO3 (BTO), critically impact optoelectronic properties. However, rationally tuning via synthesis routes obtaining insights into their on photocatalytic H2 generation is limited. Herein, the effect of heating as-synthesized BTO an atmosphere at 400 °C for hour activity investigated. Such post-synthesis modification did not induce changes bulk properties BTO, crystalline phase optical evolution under ultraviolet light decreased by ≈1.8 times after reduction treatment. Under visible (λ > nm) that majorly populates in-gap defects, virtually no was observed being subjected to process. This observation attributed enhancement density electron-trapping vacancies, revealed complementary microscopic spectroscopic tools. Insights from nonlinear measurement location states be ≈0.8 eV below conduction band BTO. Results show how vulnerable these can toward treatment with 5% its crucial efficiency. Hence, elucidating inherent nature controlling them should considered a key parameter photocatalyst design.

Language: Английский

Solar-powered photocatalysis in water purification: applications and commercialization challenges DOI Creative Commons
Marica Muscetta, Priyanka Ganguly, Laura Clarizia

et al.

Journal of environmental chemical engineering, Journal Year: 2024, Volume and Issue: 12(3), P. 113073 - 113073

Published: May 14, 2024

Although heterogeneous photocatalysis has been recognized as a promising technology for decontaminating and disinfecting municipal industrial wastewater over the last few decades, it not yet successfully transitioned from laboratory-scale research to real-world applications. This limited progress is attributed inherent physicochemical properties of most photocatalytic materials available, which exhibit reduced photoefficiency under visible light irradiation, along with multiple engineering considerations. comprehensive review delves into intricate dynamics reactions kinetics, exploring several types reactors elucidating significance employed in treatment. critical survey systematically examines effectiveness different such titania, zinc oxide graphitic carbon nitride are commercially applied reactor systems. Understanding role these essential address challenges associated Furthermore, discussion extends beyond technical aspects encompass broader landscape hindering commercialization widespread adoption technologies. By critically evaluating challenges, minireview aims provide valuable insights researchers, engineers, policymakers seeking advance implement treatment on scale. synthesis knowledge consolidates current state field outlines future prospects overcoming barriers optimizing potential processes environmental remediation.

Language: Английский

Citations

17
Recent Progress of Chemical Reactions Induced by Contact Electrification DOI Creative Commons
Xiaolin Huo, Shaoxin Li, Bing Sun

et al.

Molecules, Journal Year: 2025, Volume and Issue: 30(3), P. 584 - 584

Published: Jan. 27, 2025

Contact electrification (CE) spans from atomic to macroscopic scales, facilitating charge transfer between materials upon contact. This interfacial exchange, occurring in solid–solid (S–S) or solid–liquid (S–L) systems, initiates radical generation and chemical reactions, collectively termed contact-electro-chemistry (CE-Chemistry). As an emerging platform for green chemistry, CE-Chemistry facilitates redox, luminescent, synthetic, catalytic reactions without the need external power sources as traditional electrochemistry with noble metal catalysts, significantly reducing energy consumption environmental impact. Despite its broad applicability, mechanistic understanding of remains incomplete. In S–S is primarily driven by surface charges, whether electrons, ions, radicals, on charged solid interfaces. However, a comprehensive theoretical framework yet be established. While CE offers promising exploring interplay triboelectric via modulation, it faces significant challenges achieving scalability optimizing efficiency. contrast, S–L focuses electron critical step subsequent reactions. approach notably versatile, enabling bulk-phase solutions offering flexibility choose various solvents and/or dielectrics optimize reaction pathways, such degradation organic pollutants polymerization, etc. The formation electrical double layer (EDL), ion adsorption following transfer, plays pivotal role CE-Chemical processes within aqueous systems. EDL can exert screening effect further thereby inhibiting progress. A optimization mechanisms are elucidating pathways precise control over processes. foundation CE-Chemistry, underpins development energy-efficient environmentally sustainable methodologies, holding transformative potential advancing innovation. review consolidates recent advancements, systematically classifying progress based configurations systems underlying dynamics. To unlock full future research should prioritize strategic tuning material electronegativity, engineering sophisticated architectures, enhancement transport mechanisms, paving way innovations.

Language: Английский

Citations

1
Extremely Long-Lived Charge Donor States Formed by Visible Irradiation of Quantum Dots DOI
Micaela Homer, Helen Larson, Grant J. Dixon

et al.

ACS Nano, Journal Year: 2024, Volume and Issue: 18(35), P. 24591 - 24602

Published: Aug. 20, 2024

Using cyclic voltammetry under illumination, we recently demonstrated that CdS quantum dots (QDs) form charge donor states live for at least several minutes after illumination ends, ∼12 orders of magnitude longer than expected free carriers. This time scale suggests the conventionally accepted mechanism transfer, wherein charges directly transfer to an acceptor following exciton dissociation, cannot be complete. Because these long scales, this unconventional pathway is not readily observed using time-resolved spectroscopy probe dynamics. Here, investigated chemical nature coupled with NMR spectroscopy, X-ray diffraction, photoelectron and optical spectroscopy. Our data reveal are stored locally rather as carriers, number dependent on QD surface ligation stoichiometry. Altogether, our results confirm electrons ligated Cd, sites competent donors, storage balanced by X-type ligand desorption. We found occurs in every system studied, including CdS, CdSe, InP capped carboxylate phosphonate ligands.

Language: Английский

Citations

5
Colloidal Synthesis of Carbon Dot‐ZnSe Nanoplatelet Van der Waals Heterostructures for Boosting Photocatalytic Generation of Methanol‐Storable Hydrogen DOI Creative Commons
Dechao Chen, Rohan J. Hudson, Cheng Tang

et al.

Small, Journal Year: 2024, Volume and Issue: unknown

Published: June 8, 2024

Abstract Methanol is not only a promising liquid hydrogen carrier but also an important feedstock chemical for synthesis. Catalyst design vital enabling the reactions to occur under ambient conditions. This study reports new class of van der Waals heterojunction photocatalyst, which synthesized by hot‐injection method, whereby carbon dots (CDs) are grown in situ on ZnSe nanoplatelets (NPLs), i.e., metal chalcogenide quantum wells. The resultant organic‐inorganic hybrid nanoparticles, CD‐NPLs, able perform methanol dehydrogenation through CH splitting. heterostructure has enabled light‐induced charge transfer from CDs into NPLs occurring sub‐nanosecond timescale, with charges remaining separated across CD‐NPLs longer than 500 ns. resulted significantly heightened H 2 production rate 107 µmole·g −1 ·h and enhanced photocurrent density up 34 µA cm −2 at 1 V bias potential. EPR NMR analyses confirmed occurrence α‐CH splitting CC coupling. novel CD‐based semiconductor poised enable discovery host nano‐hybrid photocatalysts full tunability band structure, transfer, divergent surface chemistry guiding photoredox pathways accelerating reaction rates.

Language: Английский

Citations

4
S-scheme quantum dots heterojunction photocatalysts: Assembly types, mechanism insights, and design strategies DOI

Jintao Ru,

Chen‐Ho Tung, Li‐Zhu Wu

et al.

Nano Research, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 5, 2024

Language: Английский

Citations

4
QD/SnO2 Photoactivated Chemoresistive Sensor for Selective Detection of Primary Alcohols at Room Temperature DOI Creative Commons

Maria Yu. Skrypnik,

Vadim Platonov, Daria A. Kurtina

et al.

Chemosensors, Journal Year: 2025, Volume and Issue: 13(1), P. 20 - 20

Published: Jan. 16, 2025

Sensors based on nanocomposites of quantum dots (QDs) and wide-gap metal oxides are exceptional interest for photoactivated detection toxic pollutant gases without thermal heating. However, the class detecting has been limited almost exclusively to oxidizing like NO2. Here, we designed a sensor selective primary alcohols at room temperature using CdSe coupled SnO2 semiconductor matrix. Our concept operations is photochemical reaction via QD-SnO2 charge transfer does not involve chemisorbed oxygen, which traditional operation oxide sensors. We demonstrated an efficient response C1–C4 ppm concentration under photoexcitation with yellow LED in absence signal from other volatile organic compounds (VOCs). believe that proposed opens up new ways design sensors heating VOCs.

Language: Английский

Citations

0
Tracking Charge Dynamics in a Silver Single-Atom Catalyst During the Light-Driven Oxidation of Benzyl Alcohol to Benzaldehyde DOI Creative Commons

Areti Moutsiou,

Andrea Olivati,

Luis A. Cipriano

et al.

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 5601 - 5613

Published: March 21, 2025

Understanding charge transfer in light-driven processes is crucial for optimizing the efficiency and performance of a photocatalyst, as directly influences separation migration photogenerated carriers determines overall reaction rate product formation. However, achieving this understanding remains challenging context single-atom photocatalysis. This study addresses gap investigates an Ag-based catalyst (Ag1@CNx) photocatalytic oxidation benzyl alcohol to benzaldehyde. Comprehensive characterization was conducted using battery diffractive, textural, spectroscopic, microscopic methods, confirming crystallinity, porosity, elemental composition, atomic dispersion silver atoms. material displayed efficient selective Density functional theory calculations were used rationalize structure elucidate mechanism, unveiling role holes lowering energy barriers. Time-resolved transient spectroscopic studies monitor dynamics charges reaction, revealing lifetimes behaviors excited states within catalyst. Specifically, introduction atoms led significant enhancement state lifetime, which favors hole-transfer presence alcohol. indicated that photoexcited effectively transferred reactant, thereby driving process oxygen. These mechanistic insights are pivotal spectroscopically elucidating mechanism can be practically applied design photocatalysts more rationally, targeting materials combine both rapid reductive quenching metal.

Language: Английский

Citations

0
Manipulating Charge Dynamics in Carbon Nitride by Carbon Dot Doping for Efficient Photocatalysis DOI Creative Commons

Lingfeng Ouyang,

Maggie Ng, Zhiyuan Zhou

et al.

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: April 26, 2025

Abstract Graphitic carbon nitride (g‐C 3 N 4 ), a prominent metal‐free semiconductor photocatalyst, faces limitations due to its high exciton binding energy. While significant efforts have been focused on optimizing charge‐carrier processes, the interplay of and free carrier in this system received less attention. Herein, density‐functional theory (DFT) time‐dependent DFT calculations demonstrate that dot‐functionalized g‐C /CD), synthesized via facile thermal polymerization, shifts excited state from localized charge transfer characteristics. The /CD exhibits reduced energy 41.0 24.6 meV, as shown by temperature‐dependent photoluminescence spectroscopy. Particularly, /CD‐10 (10 wt.% CD solution precursors) achieves 3‐fold increase photodegradation rate ( k = 0.020 min⁻¹) an emerging environmental pollutant, levofloxacin (LEV), under 10 W LED light. Enhanced photocatalytic performances correlate with optimized band structure efficient transport, confirmed photophysical photoelectrochemical analyses. Although lifetime is slightly compared pristine , activity remains unaffected, underscoring critical role enhancing efficiency. This work offers insights onto potential manipulating dynamics for improved ‐based photocatalysis applications.

Language: Английский

Citations

0
Electron Transport Chain-Inspired Coordination Polymer for Macroscopic Spatiotemporal Scales of Charge Separation and Transport in Photocatalysis DOI Creative Commons

Lin Ma,

Tiexin Zhang, Mochen Li

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Inspired by electron transport chain, segregated dye stacking was assembled in a coordination polymer, which endowed photocatalysis with macroscopic spatiotemporal charge separation and for reactions separated biomimetic compartments.

Language: Английский

Citations

3
Extremely long-lived charge donor states formed by visible irradiation of quantum dots DOI Creative Commons
Micaela Homer, Helen Larson, Grant J. Dixon

et al.

Published: April 23, 2024

Using cyclic voltammetry under illumination, we recently demonstrated that CdS quantum dots (QDs) form charge donor states live for at least several minutes after illumination ends, ~12 orders of magnitude longer than expected free carriers. This timescale suggests the conventionally accepted mechanism transfer, wherein charges directly transfer to an acceptor following exciton dissociation, cannot be complete. Because these long timescales, this unconventional pathway is not readily observed using time-resolved spectroscopy probe dynamics. Here, investigated chemical nature coupled with NMR spectroscopy, X-ray diffraction, photoelectron and optical spectroscopy. Our data reveal are stored locally rather as carriers, number dependent on QD surface ligation stoichiometry. Altogether, our results confirm electrons ligated Cd, sites competent donors, storage balanced by X-type ligand desorption. We found occurs in every system studied, including CdS, CdSe, InP capped carboxylate phosphonate ligands.

Language: Английский

Citations

2