Solution-Processed n-Type Graphene Doping for Cathode in Inverted Polymer Light-Emitting Diodes

doi:10.1021/acsami.7b15307

Title: Solution-Processed n-Type Graphene Doping for Cathode in Inverted Polymer Light-Emitting Diodes

Abstract

n-Type doping with (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl) dimethylamine (N-DMBI) reduces a work function (WF) of graphene by ~0.45 eV without significant reduction of optical transmittance. Solution process of N-DMBI on graphene provides effective n-type doping effect and air-stability at the same time. Although neutral N-DMBI act as an electron receptor leaving the graphene p-doped, radical N-DMBI acts as an electron donator leaving the graphene n-doped, which is demonstrated by density functional theory. We also verify the suitability of N-DMBI-doped n-type graphene for use as a cathode in inverted polymer light-emitting diodes (PLEDs) by using various analytical methods. Inverted PLEDs using a graphene cathode doped with N-DMBI radical showed dramatically improved device efficiency (~13.8 cd/A) than did inverted PLEDs with pristine graphene (~2.74 cd/A). Finally, N-DMBI-doped graphene can provide a practical way to produce graphene cathodes with low WF in various organic optoelectronics.

Authors:

Kwon, Sung-Joo ^[1]; Han, Tae-Hee ^[2]; Kim, Young-Hoon ^[3]; Ahmed, Towfiq ^[4]; Seo, Hong-Kyu ^[1]; Kim, Hobeom ^[5]; Kim, Dong Jin ^[6]; Xu, Wentao ^[7];

^[8];

^[4];

^[7]

Pohang Univ. of Science and Technology (POSTECH) (Korea, Republic of). Dept. of Materials Science and Engineering
Seoul National Univ. (Korea, Republic of). Dept. of Materials Science and Engineering; Univ. of California, Los Angeles, CA (United States). Dept. of Materials Science and Engineering; Univ. of California, Los Angeles, CA (United States). California NanoSystems Inst.
Seoul National Univ. (Korea, Republic of). Dept. of Materials Science and Engineering; Seoul National Univ. (Korea, Republic of). Research Inst. of Advanced Materials; Seoul National Univ. (Korea, Republic of). BK21 PLUS SNU Materials Division for Educating Creative Global Leaders
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Seoul National Univ. (Korea, Republic of). Dept. of Materials Science and Engineering
Seoul National Univ. (Korea, Republic of). Program in Nano Science and Technology, Graduate School of Convergence Science and Technology
Seoul National Univ. (Korea, Republic of). Dept. of Materials Science and Engineering; Seoul National Univ. (Korea, Republic of). Research Inst. of Advanced Materials
Seoul National Univ. (Korea, Republic of). Program in Nano Science and Technology, Graduate School of Convergence Science and Technology; Seoul National Univ. (Korea, Republic of). Dept. of Chemistry

Publication Date:: 2018-01-11

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

OSTI Identifier:: 1418760

Report Number(s):: LA-UR-16-28960
Journal ID: ISSN 1944-8244

Grant/Contract Number:: AC52-06NA25396

Resource Type:: Journal Article: Accepted Manuscript

Journal Name:: ACS Applied Materials and Interfaces

Additional Journal Information:: Journal Volume: 10; Journal Issue: 5; Journal ID: ISSN 1944-8244

Publisher:: American Chemical Society (ACS)

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; Material Science

Citation Formats


                    Kwon, Sung-Joo, Han, Tae-Hee, Kim, Young-Hoon, Ahmed, Towfiq, Seo, Hong-Kyu, Kim, Hobeom, Kim, Dong Jin, Xu, Wentao, Hong, Byung Hee, Zhu, Jian-Xin, and Lee, Tae-Woo. Solution-Processed n-Type Graphene Doping for Cathode in Inverted Polymer Light-Emitting Diodes.  United States: N. p., 2018. 
        Web.  doi:10.1021/acsami.7b15307.

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                    Kwon, Sung-Joo, Han, Tae-Hee, Kim, Young-Hoon, Ahmed, Towfiq, Seo, Hong-Kyu, Kim, Hobeom, Kim, Dong Jin, Xu, Wentao, Hong, Byung Hee, Zhu, Jian-Xin, & Lee, Tae-Woo. Solution-Processed n-Type Graphene Doping for Cathode in Inverted Polymer Light-Emitting Diodes.  United States.  doi:10.1021/acsami.7b15307.

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                    Kwon, Sung-Joo, Han, Tae-Hee, Kim, Young-Hoon, Ahmed, Towfiq, Seo, Hong-Kyu, Kim, Hobeom, Kim, Dong Jin, Xu, Wentao, Hong, Byung Hee, Zhu, Jian-Xin, and Lee, Tae-Woo. Thu .  
        "Solution-Processed n-Type Graphene Doping for Cathode in Inverted Polymer Light-Emitting Diodes".  United States.  doi:10.1021/acsami.7b15307.  https://www.osti.gov/servlets/purl/1418760.

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@article{osti_1418760,

  title        = {Solution-Processed n-Type Graphene Doping for Cathode in Inverted Polymer Light-Emitting Diodes},

  author       = {Kwon, Sung-Joo and Han, Tae-Hee and Kim, Young-Hoon and Ahmed, Towfiq and Seo, Hong-Kyu and Kim, Hobeom and Kim, Dong Jin and Xu, Wentao and Hong, Byung Hee and Zhu, Jian-Xin and Lee, Tae-Woo},

  abstractNote = {n-Type doping with (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl) dimethylamine (N-DMBI) reduces a work function (WF) of graphene by ~0.45 eV without significant reduction of optical transmittance. Solution process of N-DMBI on graphene provides effective n-type doping effect and air-stability at the same time. Although neutral N-DMBI act as an electron receptor leaving the graphene p-doped, radical N-DMBI acts as an electron donator leaving the graphene n-doped, which is demonstrated by density functional theory. We also verify the suitability of N-DMBI-doped n-type graphene for use as a cathode in inverted polymer light-emitting diodes (PLEDs) by using various analytical methods. Inverted PLEDs using a graphene cathode doped with N-DMBI radical showed dramatically improved device efficiency (~13.8 cd/A) than did inverted PLEDs with pristine graphene (~2.74 cd/A). Finally, N-DMBI-doped graphene can provide a practical way to produce graphene cathodes with low WF in various organic optoelectronics.},

  doi          = {10.1021/acsami.7b15307},

  journal      = {ACS Applied Materials and Interfaces},

  issn         = {1944-8244},

  number       = 5,

  volume       = 10,

  place        = {United States},

  year         = {2018},

  month        = {1}

}

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DOI: 10.1021/acsami.7b15307

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Figures / Tables:

Figure 1: Schematics of inverted PLEDs with N-DMBI-doped graphene, and molecular structure of N-DMBI.

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