Molecular Engineering of a Donor–Acceptor Polymer To Realize

Jul 17, 2019 - As depicted in Figure 3b, the obtained data showed good agreement with the equation, resulting in a hole mobility between 7.5 × 10–5...
0 downloads 0 Views 1MB Size
Subscriber access provided by BUFFALO STATE

Organic Electronic Devices

Molecular engineering of donor-acceptor polymer to realize a single band absorption toward red-selective thin film organic photodiode Syed Zahid Hassan, Hyung Jin Cheon, Changwon Choi, Seongwon Yoon, Mingyun Kang, Jangwhan Cho, Yun Hee Jang, Soon-Ki Kwon, Dae Sung Chung, and Yun-Hi Kim ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.9b08326 • Publication Date (Web): 17 Jul 2019 Downloaded from pubs.acs.org on July 17, 2019

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

Molecular engineering of donor-acceptor polymer to realize a single band absorption toward red-selective thin film organic photodiode Syed Zahid Hassan,†,∥ Hyung Jin Cheon,‡,∥ Changwon Choi,† Seongwon Yoon,† Mingyun Kang,† Jangwhan Cho,† Yun Hee Jang,† Soon-Ki Kwon,§ Dae Sung Chung,*,† Yun-Hi Kim*,‡ †Department

of Energy Science & Engineering, Daegu Gyeongbuk Institute of Science &

Technology (DGIST), Daegu, 42988, Republic of Korea ‡Department

of Chemistry and RIGET, Gyeongsang National University, Jinju, 52828, Republic

of Korea §Department

of Materials Engineering and Convergence Technology and ERI, Gyeongsang

National University, Jinju, 660-701, Republic of Korea KEYWORDS Color-selective, donor-acceptor copolymers, diketopyrrolopyrroles, organic photodiodes, image sensors

ABSTRACT

ACS Paragon Plus Environment

1

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 30

Herein we explore the strategy of realizing a red-selective thin-film organic photodiode (OPD) by synthesizing a new copolymer with a highly selective red-absorption feature. PCZ-Th-DPP, with phenanthrocarbazole (PCZ) and diketopyrrolopyrrole (DPP) as donor and acceptor units, respectively, was strategically designed/synthesized based on a time-dependent density functional theory calculation, which predicted the significant suppression of the band II absorption of PCZTh-DPP due to the extremely efficient intramolecular charge transfer. We demonstrate that the synthesized PCZ-Th-DPP exhibits not only a high absorption coefficient within the red-selective band I region, as theoretically predicted, but also a preferential face on intermolecular structure in the thin film state, which is beneficial for vertical charge extraction as an outcome of a glancing incidence X-ray diffraction study. By employing PCZ-Th-DPP as a photoactive layer of Schottky OPD, to fully match its absorption characteristic to the spectral response of the red-selective OPD, we demonstrate a genuine red-selective specific detectivity in the order of 1012 Jones while maintaining a thin active layer thickness of ~300 nm. This work demonstrates the possibility of realizing a full color image sensor with a synthetic approach to the constituting active layers without optical manipulation.

INTRODUCTION Recently, organic photodiodes (OPDs), using organic semiconductors as photoactive layers with a high extinction coefficient and tunable absorption spectrum, have attracted much attention as possible alternatives of Si photodiodes.1-3 This is because the inherent characteristics of organic semiconductors can be directly connected to color filter-free thin film type OPDs, which have a unique advantage in enhancing the degree of integration of an image sensor.4-7 To date, various methods of realizing color-selective OPDs have been introduced that can be categorized into two

ACS Paragon Plus Environment

2

Page 3 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

groups: 1) synthesizing Red/Green/Blue-selective organic semiconductors and fully reflecting their own absorption feature to the detectivity spectrum8-18; 2) optically/electrically manipulating the detectivity spectrum using strategically designed device architecture so that artificial Red/Green/Blue-selectivity can be established.19-21 In terms of narrowband color-selectivity, the second method represented by the charge collection narrowing technique has demonstrated more outstanding performances resulting in FWHM (full-width-half-maximum) of 1.5 μm), which can limit the scaling down of pixel size in organic image sensors. Therefore, the first method of fully reflecting the absorption feature of newly synthesized color-selective organic semiconductors to produce a spectrum can be more attractive approach at this stage, at least to satisfy the thin film nature of photodiodes (