g‐C₃N₄‐Based Heterostructured Photocatalysts

Advanced Energy Materials, Journal Year: 2017, Volume and Issue: 8(3)

Published: Sept. 21, 2017

Abstract Photocatalysis is considered as one of the promising routes to solve energy and environmental crises by utilizing solar energy. Graphitic carbon nitride (g‐C 3 N 4 ) has attracted worldwide attention due its visible‐light activity, facile synthesis from low‐cost materials, chemical stability, unique layered structure. However, pure g‐C photocatalyst still suffers low separation efficiency photogenerated charge carriers, which results in unsatisfactory photocatalytic activity. Recently, ‐based heterostructures have become research hotspots for their greatly enhanced carrier performance. According different transfer mechanisms carriers between coupled components, heterostructured photocatalysts can be divided into following categories: conventional type II heterojunction, Z‐scheme p–n /metal heterostructure, /carbon heterostructure. This review summarizes recent significant progress on design special separation/transfer carriers. Moreover, applications fields, e.g., water splitting, dioxide reduction, degradation pollutants, are also reviewed. Finally, some concluding remarks perspectives challenges opportunities exploring advanced presented.

Language: Английский

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Metal-Free Photocatalyst for H₂ Evolution in Visible to Near-Infrared Region: Black Phosphorus/Graphitic Carbon Nitride

Journal of the American Chemical Society, Journal Year: 2017, Volume and Issue: 139(37), P. 13234 - 13242

Published: Aug. 31, 2017

In the drive toward green and sustainable chemistry, exploring efficient stable metal-free photocatalysts with broadband solar absorption from UV to near-infrared region for photoreduction of water H2 remains a big challenge. To this end, binary nanohybrid (BP/CN) two-dimensional (2D) black phosphorus (BP) graphitic carbon nitride (CN) was designed used as photocatalyst first time. During irradiation BP/CN in >420 >780 nm light, solid gas generated, respectively. Owing interfacial interaction between BP CN, charge transfer occurred, thereby enhancing photocatalytic performance. The charge-trapping processes were thoroughly investigated time-resolved diffuse reflectance spectroscopic measurement. present results show that is artificial photosynthesis renewable energy conversion.

Language: Английский

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Role of Interfaces in Two-Dimensional Photocatalyst for Water Splitting

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(3), P. 2253 - 2276

Published: Jan. 30, 2018

Hydrogen generation from the direct splitting of water by photocatalysis is regarded as a promising and renewable solution for energy crisis. The key to realize this reaction find an efficient robust photocatalyst that ideally makes use sunlight. Recently, due attractive properties such appropriate band structure, ultrahigh specific surface area, more exposed active sites, two-dimensional (2D) photocatalysts have attracted significant attention photocatalytic splitting. This Review attempts summarize recent progress in fabrication applications 2D including graphene-based photocatalysts, oxides, chalcogenides, carbon nitride, some other emerging materials construction strategies characterization techniques 2D/2D are summarized. Particular has been paid role interfaces these heterojunctions critical facilitating charge separation improving efficiency. We also critically discuss their stability Finally, we highlight ongoing challenges opportunities future development exciting still area research.

Language: Английский

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Molecule Self-Assembly Synthesis of Porous Few-Layer Carbon Nitride for Highly Efficient Photoredox Catalysis

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(6), P. 2508 - 2515

Published: Jan. 17, 2019

Polymeric carbon nitride (C3N4) has emerged as the most promising candidate for metal-free photocatalysts but is plagued by low activity due to poor quantum efficiency and specific surface area. Exfoliation of bulk crystals into ultrathin nanosheets proven be an effective widely used strategy enabling high photocatalytic performances; however, this process complicated, time-consuming, costly. Here, we report a simple bottom-up method synthesize porous few-layer C3N4, which involves molecule self-assembly layered precursors, alcohol molecules intercalation, subsequent thermal-induced exfoliation polycondensation. The as-prepared C3N4 expose more active sites greatly enhance separation charge carriers, thus exhibiting 26-fold higher hydrogen evolution than counterpart. Furthermore, find that both selectivity oxidative coupling amines imines can obtained under visible light surpass those other so far.

Language: Английский

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Metal‐Free 2D/2D Phosphorene/g‐C₃N₄ Van der Waals Heterojunction for Highly Enhanced Visible‐Light Photocatalytic H₂ Production

Advanced Materials, Journal Year: 2018, Volume and Issue: 30(25)

Published: April 30, 2018

The generation of green hydrogen (H2 ) energy using sunlight is great significance to solve the worldwide and environmental issues. Particularly, photocatalytic H2 production a highly promising strategy for solar-to-H2 conversion. Recently, various heterostructured photocatalysts with high efficiency good stability have been fabricated. Among them, 2D/2D van der Waals (VDW) heterojunctions received tremendous attention, since this architecture can promote interfacial charge separation transfer provide massive reactive centers. On other hand, currently, most are composed metal elements cost, limited reserves, hazardous impact. Hence, development metal-free desirable. Here, novel VDW heterostructure phosphorene/graphitic carbon nitride (g-C3 N4 phosphorene/g-C3 nanocomposite shows an enhanced visible-light activity 571 µmol h-1 g-1 in 18 v% lactic acid aqueous solution. This improved performance arises from intimate electronic coupling at interface, corroborated by advanced characterizations techniques, e.g., synchrotron-based X-ray absorption near-edge structure, theoretical calculations. work not only reports new photocatalyst but also sheds lights on design fabrication heterojunction applications catalysis, electronics, optoelectronics.

Language: Английский

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Applications of Phosphorene and Black Phosphorus in Energy Conversion and Storage Devices

Advanced Energy Materials, Journal Year: 2017, Volume and Issue: 8(8)

Published: Dec. 1, 2017

Abstract The successful isolation of phosphorene (atomic layer thick black phosphorus) in 2014 has currently aroused the interest 2D material researchers. In this review, first, fundamentals phosphorus allotropes, phosphorene, and phosphorus, are briefly introduced, along with their structures, properties, synthesis methods. Second, readers presented an overview energy applications. Particularly electrochemical storage, large interlayer spacing (0.53 nm) allows intercalation/deintercalation larger ions as compared to its graphene counterpart. Therefore, may possess greater potential for high performance. addition, status lithium ion batteries well secondary sodium is reviewed. Next, each application generation, conversion, storage described detail milestones challenges. These emerging applications include supercapacitors, photovoltaic devices, water splitting, photocatalytic hydrogenation, oxygen evolution, thermoelectric generators. Finally fast‐growing dynamic field research summarized perspectives on future possibilities calling efforts chemists, physicists, scientists

Language: Английский

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Black Phosphorus Rediscovered: From Bulk Material to Monolayers

Angewandte Chemie International Edition, Journal Year: 2017, Volume and Issue: 56(28), P. 8052 - 8072

Published: Jan. 23, 2017

Abstract Phosphorus is a nonmetal with several allotropes, from the highly reactive white phosphorus to thermodynamically stable black (BP) puckered orthorhombic layered structure. The bulk form of BP was first synthesized in 1914, but received little attention until it rediscovered 2014 as member new wave 2D nanomaterials. can be exfoliated single sheet that acts semiconductor tunable direct band gap, high carrier mobility at room temperature, and an in‐plane anisotropy. development applications hampered by surface degradation, thus efforts achieve effective passivation are ongoing, such its integration van der Waals heterostructures. has been tested novel nanomaterial batteries, transistors, sensors, photonics. This Review begins origin story, following path material modern few/single layers. physical chemical properties summarized, state‐of‐the‐art highlighted.

Language: Английский

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Black Phosphorus Revisited: A Missing Metal‐Free Elemental Photocatalyst for Visible Light Hydrogen Evolution

Advanced Materials, Journal Year: 2017, Volume and Issue: 29(17)

Published: Feb. 24, 2017

Metal‐free elemental photocatalysts for hydrogen (H 2 ) evolution are more advantageous than the traditional metal‐based inorganic since nonmetal elements generally cheaper, earth‐abundant, and environmentally friendly. Black phosphorus (BP) has been attracting increasing attention in recent years based on its anisotropic 2D layered structure with tunable bandgap range of 0.3–2.0 eV; however, application BP photocatalytic H scarcely reported experimentally although being theoretically predicted. Herein, first time, visible light nanosheets prepared via a facile solid‐state mechanochemical method by ball‐milling bulk is reported. Without using any noble metal cocatalyst, rate reaches 512 µmol h −1 g , which ≈18 times higher that BP, comparable or even graphitic carbon nitrides (g‐C 3 N 4 ).

Language: Английский

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Metal-free photocatalysts for hydrogen evolution

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(6), P. 1887 - 1931

Published: Jan. 1, 2020

This article provides a comprehensive review of the latest progress, challenges and recommended future research related to metal-free photocatalysts for hydrogen productionviawater-splitting.

Language: Английский

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Two-dimensional materials in semiconductor photoelectrocatalytic systems for water splitting

Energy & Environmental Science, Journal Year: 2018, Volume and Issue: 12(1), P. 59 - 95

Published: Oct. 10, 2018

Hydrogen production via solar water splitting can be enhanced by combining semiconductors with various 2-dimensional materials.

Language: Английский

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