Tunable high workfunction contacts: Doped graphene

Legesse, Merid; Rashkeev, Sergey N.; Al-Dirini, Feras; Alharbi, Fahhad H.

doi:10.1016/j.apsusc.2019.144893

Cited by 11 publications

(23 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Generally, 2D materials with low ϕ values are needed for cathode applications, whereas those with high ϕ values are required for anode applications. − To achieve nanoscale ϕ modulation of 2D materials, various methods, such as incorporating self-assembled monolayers or metal oxide layers, − substrate orientations, exerting an external electric field, introducing irradiation-induced defects, and dopings, ,, have been developed. Interestingly, the direct adsorption or decoration of alkali/alkaline earth metals; IIIA, IVA, VA, VIA, and VIIA group atoms; transition metals; and organo-functional groups or gas molecules has been theoretically and experimentally reported to be a simple and effective method for tailoring the ϕ values and electronic properties of 2D nanomaterials including graphene, silicene, and BN sheets. ,− These pioneering studies suggest that the adsorption of alkali/alkaline earth metals, ,− IIIA group atoms (Al, Ga, and In), a IVA group atom (Sn), transition metals (Ti, Fe, and Pd), organo-functional groups (−(CH 2 ) 2 NHCH 3 , −OCH 3 , −C 6 H 5 , −NH 2 , −CH 3 , and −OH), and gas molecules (CO/COCl 2 ) always leads to a decrease in the ϕ of a 2D system; contrarily, the functionalization or adsorption of VA group atoms (N, P, and As), VIA group atoms (O, S, and Se), transition-metal chlorides (AuCl 3 , IrCl 3 , MoCl 3 , OsCl 3 , PdCl 2 , and RhCl 3 ), and −CN always causes an increase in the ϕ of a 2D system.…”

Section: Introductionmentioning

confidence: 99%

Imparting α-Borophene with High Work Function by Fluorine Adsorption: A First-Principles Investigation

et al. 2021

View full text Add to dashboard Cite

Increasing the work function of borophene over a large range is crucial for the development of borophene-based anode materials for highly efficient electronic devices. In this study, the effect of fluorine adsorption on the structures and stabilities, particularly on the work function, of α-borophene (BBP), was systematically investigated via first-principles density functional theory. The calculations indicated that BBP was well-stabilized by fluorine adsorption and the work functions of metallic fluorineadsorbed BBPs (F n -BBPs) sharply increased with increasing fluorine content. Moreover, the work function of F-BBP was close to that of the frequently used anode material Au and even, for other F n -BBPs, higher than that of Pt. Furthermore, we have comprehensively discussed the factors, including substrate deformation, charge transfer, induced dipole moment, and Fermi and vacuum energy levels, affecting the improvement of work function. Particularly, we have demonstrated that the charge redistribution of the substrate induced by the bonding interaction between fluorine and the matrix predominantly contributes to the observed increase in the work function. Additionally, the effect of fluorine adsorption on the increase in the work function of BBP was significantly stronger than that of silicene or graphene. Our results concretely support the fact that F n -BBPs can be extremely attractive anode materials for electronic device applications.

show abstract

Section: Introductionmentioning

confidence: 99%

Imparting α-Borophene with High Work Function by Fluorine Adsorption: A First-Principles Investigation

et al. 2021

View full text Add to dashboard Cite

show abstract

“…These synthetic methods have produced graphene materials with monodopants [28,29] and codopants. [30,31] Importantly, experimentalists [32,33] and theoreticians [34] have joined forces to understand the mechanism of controlled growth with rationally designed doping features and to develop synthetic routes that are simple, economical, green, and scalable. [16,[35][36][37] These issues are critical to the reliable and large-scale production and application of graphene derivatives.…”

Section: Introductionmentioning

confidence: 99%

Advances and Trends in Chemically Doped Graphene

Ullah

Shi

Zhou

et al. 2020

Adv Materials Inter

View full text Add to dashboard Cite

Chemically doped graphene materials are fascinating because these have different desirable attributes with possible synergy. The inert and gapless nature of graphene can be changed by adding a small number of heteroatoms to substitute carbon in the lattice. The doped material may display superior catalytic activities; durable, fast, and selective sensing; improved magnetic moments; photoresponses; and activity in chemical reactions. In the current review, recent advances are covered in chemically doped graphene. First, the different types of heteroatoms, their bonding configurations, and briefly their properties are discussed. This is followed by the description of various synthesis and analytical methods essential for assessing the characteristics of heterographene with specific focus on the selected graphene materials of different dopants (particularly, single dopants, including N, B, S, P, first three halogens, Ge, and Ga, and codopants, such as N/O), and more importantly, up‐to‐date applications enabled by the intentional doping. Finally, outlook and perspectives section review the existing challenges, future opportunities, and possible ways to improve the graphitic materials. The goal is to update and inspire the readers to establish novel doped graphene with valuable properties and for current and futuristic applications.

show abstract

“…Chemical doping of heteroatoms into CQDs serves as an effective strategy as follows in previous studies: 82‐86 (a) Adjusting the work function of HTL; (b) Promoting efficient charge extraction; (c) Generating high short‐circuit current density. In general, in the case of non‐metallic dopants, although energy band alignment (work function adjustment) through doping is possible, it leads to an increase in electrical resistance 85,86 . In contrast, when doping with a metal dopant (eg, Ag), electrical conductivity is improved, and charge transfer is enhanced 86,87 .…”

Section: Resultsmentioning

confidence: 99%

“…In general, in the case of non-metallic dopants, although energy band alignment (work function adjustment) through doping is possible, it leads to an increase in electrical resistance. 85,86 In contrast, when doping with a metal dopant (eg, Ag), electrical conductivity is improved, and charge transfer is enhanced. 86,87 In this context, there have been few reports of synthesis and applications for Ag-doped CQD in PSCs.…”

Section: Conductive Polymer Nanocomposites As Hole Transfer Layermentioning

confidence: 99%

“…[79][80][81] The above results are summarised as follows. Chemical doping of heteroatoms into CQDs serves as an effective strategy as follows in previous studies: [82][83][84][85][86] (c) Generating high short-circuit current density. In general, in the case of non-metallic dopants, although energy band alignment (work function adjustment) through doping is possible, it leads to an increase in electrical resistance.…”

Section: Conductive Polymer Nanocomposites As Hole Transfer Layermentioning

confidence: 99%

See 1 more Smart Citation

Formulation of conductive nanocomposites by incorporating silver‐doped carbon quantum dots for efficient charge extraction

Kim

Nguyen

Jang

et al. 2021

Intl J of Energy Research

View full text Add to dashboard Cite

Summary Poly(3,4‐ethylenedioxy thiophene):poly(styrenesulfonate) (PEDOT:PSS) has been investigated as a hole transport material in organic‐inorganic hybrid perovskite solar cells (PSCs) with a p‐i‐n architecture. However, the intrinsic acidic nature of PEDOT:PSS induces interfacial protonation and degrades the quality of the thin film, resulting in low charge conductivity, low perovskite crystallinity, and poor device stability. In this work, we demonstrate the effect of adding carbon quantum dots doped with silver (Ag‐CQDs) to the PEDOT:PSS hole transport layer (HTL) to improve charge extraction, increase electrical conductivity, and hence, enhance the performance of hybrid PSCs. The proposed method enables facile one‐step hydrothermal synthesis of the Ag‐CQDs in the presence of a nitrogen‐containing carbon precursor. The incorporation of PEDOT:PSS containing Ag‐CQDs in PSCs noticeably increased the short circuit current density (Jsc) in the optimised devices, enhancing the device performance and ensuring long‐term durability of PSCs, compared with the pristine. The performance improvement is the result of highly efficient hole extraction because of the enhancement of electrical properties of PEDOT:PSS by Ag‐CQD. It is also attributed to the improved perovskite crystallinity, which depends on the increased surface energy of HTL. This work provides an efficient route to realise more stable PSCs capable of delivering outstanding charge dynamics.

show abstract

Tunable high workfunction contacts: Doped graphene

Cited by 11 publications

References 60 publications

Imparting α-Borophene with High Work Function by Fluorine Adsorption: A First-Principles Investigation

Imparting α-Borophene with High Work Function by Fluorine Adsorption: A First-Principles Investigation

Advances and Trends in Chemically Doped Graphene

Formulation of conductive nanocomposites by incorporating silver‐doped carbon quantum dots for efficient charge extraction

Contact Info

Product

Resources

About