Si Heterojunction Hybrid Solar Cells with Rubrene:DMSO

Subscriber access provided by University of Sussex Library

C: Energy Conversion and Storage; Energy and Charge Transport

Polymer/Si Heterojunction Hybrid Solar Cells with Rubrene:DMSO Organic Semiconductor Film as an Electron-Selective Contact Linlin Yang, Jianhui Chen, Kunpeng Ge, Jianxin Guo, Qingchun Duan, Feng Li, Ying Xu, and Yaohua Mai J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.8b07987 • Publication Date (Web): 26 Sep 2018 Downloaded from http://pubs.acs.org on September 27, 2018

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 29 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

The Journal of Physical Chemistry

Polymer/Si Heterojunction Hybrid Solar Cells with Rubrene:DMSO Organic Semiconductor Film as an Electron-Selective Contact Linlin Yang1, Jianhui Chen 1*, Kunpeng Ge1, Jianxin Guo1, Qingchun Duan2, Feng Li2, Ying Xu1*, Yaohua Mai3*

1

Hebei Key Lab of Optic-electronic Information and Materials, College of Physics

Science and Technology, Hebei University, Baoding 071002, China 2

State Key Laboratory of Photovoltaic Materials & Technology, Yingli Green Energy

Holding Co., Ltd., Baoding 071051, China 3

Institute of New Energy Technology, College of Information Science and Technology,

Jinan University, Guangzhou, 510632, China

Abstract. An

organic

semiconductor

composite

thin

film,

5,

6,

11,

12-tetraphenylnaphthacene:Dimethyl sulfoxide (rubrene:DMSO), is fabricated by dissolving rubrene powder into the DMSO solvent to form the precursor solution using spin-coating technology. It is found that the work function of the rubrene:DMSO thin film is 3.84 eV, which is lower than the electron affinity of the n-Si (4.05 eV), leading to the efficacy of the rubrene:DMSO film as an electron-selective contact to tailor energy band structures in the current dopant-free silicon (Si)-based heterojunction solar cells. When the rubrene:DMSO film is introduced

to

the

poly(3,4-ethylenedioxythiophene):poly(stylenesulfonate) 1

ACS Paragon Plus Environment

The Journal of Physical Chemistry 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

(PEDOT:PSS)/Si

heterojunction hybrid solar cells to form an organic/c-Si/organic

structure, the open circuit voltage and fill factor of the solar cell device presents significant improvement, leading to a relative increase of 27% in power conversion efficiency. This is ascribed to the reduction of recombinative and resistive losses at the rear side of the device, which is contributed by an efficient electron-selective rubrene:DMSO contact. This all-organic carrier-selective contact promises to revolutionize by providing inexpensive, lightweight and capable ubiquitous components that are coated onto ultrathin c-Si solar cells.

2


Page 2 of 29

Page 3 of 29 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


1. Introduction. The solar cell device can be simply divided into: absorption layer, hole-selective contact layer and electron-selective contact layer. Taking an n-type crystalline silicon (c-Si) as the absorption layer of the solar cell for example, hole-selective contact, has been achieved by the addition of a boron dopant into Si bulk under high temperature (~900oC) for the traditional c-Si solar cells1, or Si-based thin film (i.e., p-type hydrogenated amorphous silicon(a-Si:H(p))) for the silicon heterojunction (SHJ) solar cells2. Dopant-free asymmetric heterocontacts (DASH) solar cells use the material of molybdenum or tungsten oxide to achieve hole-selective contact3-4. Organic-inorganic hybrid solar cells use p-type polymer such as poly(3,4-ethylenedioxythiophene):poly(stylenesulfonate)

(PEDOT:PSS)5

or

poly(3-hexylthiophene) (P3HT)6-7, to promote the transparent of holes. As for electron-selective contact, traditional c-Si solar cells always adopt the method of diffusing phosphorus into the Si bulk to achieve the highly transparent of electrons 8

.SHJ solar cells employ plasma enhanced chemical vapor deposition (PECVD)

technology to directly grow phosphorus-doped a-Si:H(a-Si:H(n)) film as an efficient electron-selective contact layer9. DASH solar cells use various compounds, such as TiO2/LiF, KFx, and CsFx, to act a role of electron-selective contact 10-11. Very recently, organic-inorganic hybrid solar cell becomes a promising candidate for the next generation low-cost photovoltaics and has attracted extensive research interest owing to its simple geometry, low fabrication temperature, high-vacuum-free process and potential low-cost. The first hybrid solar cell was 3



successfully fabricated with the power conversion efficiency (PCE) of 1.7% in the year of 200212. After over ten years of development, the PCE of the hybrid solar cell has reached to 16.2 %13. The vast majority of publications in this field focus on a hybrid Schottky junction (hole-selective contact) at the front side of the device for the study of the organic emitter properties, hybrid interface modification and organic layer stability improvement. The rear side of this type solar cell has just been investigated in recent years for an efficient electron-selective contact. Materials, such as LiF14, Cs2CO315, Mg16, MgNd17, TiOx18 and SiOx/Mg19, have been studied. Such device structure of organic/c-Si/organic hybrid solar cells, i.e., in which both hole-selective contact and electron-selective contact used organic materials, will be a highly desirable goal to simplify the manufacturing process and reduce the production cost. This organic carrier-selective contact promises to revolutionize by providing inexpensive, lightweight and capable ubiquitous components that are coated onto ultrathin c-Si solar cells. Little work has been done on organic electron-selective contact other than studies by Sun et al 20-21. 5, 6, 11, 12-tetraphenylnaphthacene (rubrene), as an organic small molecule semiconductor material, with high electrical conductivity and carrier mobility (20 cm2 V-1 s-1)22-23, has been widely studied for applications in optoelectronic devices such as thin-film transistors (TFTs)24, organic field effect transistors (OFETs)25, organic light emitting diodes (OLEDs)26, and organic photovoltaic (OPV) devices27. Rubrene, has been used as a fluorescent material to act as a role of a tracer in medical research28. Rubrene has so many excellent properties that has attracted considerable interest. The 4


Page 4 of 29

Page 5 of 29 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


method widely accepted depositing a rubrene thin film is thermal evaporation. In this work, an organic semiconductor composite thin films, rubrene:Dimethyl sulfoxide (rubrene:DMSO), were fabricated by spin-coating. It is found that the rubrene:DMSO thin film has a low work function of 3.84eV, being lower than the electron affinity of the n-Si (4.05eV), which could tailor energy band structures of organic/c-Si heterojunction solar cells. The rubrene:DMSO thin layer is introduced to the rear side of PEDOT:PSS/Si heterojunction hybrid solar cells as efficient electron-selective contact, leading to a significant improvement in the device performances.

2. Experimental Section. An n-type Czochralski (Cz)-grown-single-side-polished wafer, with the resistivity of 0.1-0.3 Ω·cm, the thickness of 290 µm and the orientation of (100), was used as the substrate of the hybrid solar cell. The wafers were first dipped in hydrofluoric acid solution (10%) for 3 minutes (min) to remove the native oxide layer of Si surface and to terminate the dangling bonds. PEDOT:PSS solution mixed with 6 wt.% ethylene glycol was spin-coated twice on the mirrored surface of the Si and annealed at 130 oC for 10 min at the atmosphere, respectively. 1 mg rubrene powder dissolved in 1 ml solvent DMSO, forming the rubrene:DMSO precursor solution. The precursor solution, which had ultrasonic shaken for 2 hours and placed for 10 hours, was spin-coated on the other side of the Si wafer and annealed at 130 oC for 10 min at the atmosphere. Note that each layer is required to anneal for the solvent release. Subsequently, Ag metal film was deposited onto the back surface of the Si wafer as 5



well as silver grid electrodes were deposited onto the PEDOT:PSS layer through a shadow mask by vacuum thermal evaporation. A sample only with Ag electrode on the rear side of Si wafer was fabricated as the reference device. The surface morphology of the organic small molecule film, rubrene:DMSO, was investigated by scanning electron microscopy (SEM) spectra. The chemical composition of the rubrene:DMSO thin film was analyzed by X-ray photoelectron spectroscopy (XPS) (Thermoescalab 250XI, Al-Ka 1486.6 eV). The work function of the rubrene:DMSO thin film was measured by ultraviolet photoelectron spectroscopy (UPS)(Thermo Scientific ESCALab 250Xi (He I, 21.22 eV)). The photovoltaic characteristics of the solar cell devices were characterized by current density-voltage (J-V) plots under a standard test condition (AM 1.5, 100 mW/cm2 and 25 oC). Electrochemical impedance spectroscopy (EIS) of the solar cell devices were tested by Zahner Ennium electrochemical analyzer (PP211). The voltage-decay of the device was obtained from the Dyenamo Toolbox (DN-AE01).

3. Results and Discussion.

6


Page 6 of 29

Page 7 of 29 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


Figure 1. The molecular structure of (a) rubrene and (b) DMSO. (c) The picture of rubrene:DMSO solution. (d) The SEM image (e) the XPS spectra of the rubrene:DMSO organic thin film on Si substrate.

Figure 1a and Figure 1b show the molecular structure of the rubrene and DMSO, respectively. The rubrene is comprised of four phenyl groups and one tetracene ring, and DMSO two methyl groups and one sulfur-oxygen double bond. Figure 1c displays the picture of the rubrene:DMSO precursor solution. Figure 1d shows the SEM image of the rubrene:DMSO thin film. As observed, the rubrene particles with large grain sizes in the range of 100-300 nm (see the inset in Figure 1d) disorganizedly distribute on the Si substrate surface. The XPS spectra of the rubrene:DMSO thin film on the Si substrate is shown in Figure 1e. Here, the electron binding energy of 168 eV appears in S 2p peak position, corresponding to valence states of S4+, indicating that the fabricated thin film contains the DMSO.

7



Figure 2. (a) UPS cut off spectra of rubrene:DMSO thin film. (b) The band diagram of PEDOT:PSS/Si heterojunction hybrid solar cells.

The performance of the OPV device is mainly determined by the energy difference between the highest occupied molecular orbital (HOMO) level of the donor and the lowest unoccupied molecular orbital (LUMO) level of the acceptor29. Hence, it is important to study the HOMO and the LUMO of the material in the OPV devices. However, in Si solar cells, the performance of the device is usually determined by the built-in electric field, which is dependent on the difference of work function between absorption layer and hole/electron-selective contact layer. Thus, it is imperative to know the work function of the contact materials. Figure 2a shows the UPS spectrum of the rubrene:DMSO thin film, and the work function is identified to be 3.84 eV. It is not expected that the rurbrene:DMSO thin film is a low work function material. Such a low work function material can be supposed to introduce into the rear side of n-Si to function as a back surface filed (BSF). Figure 2b shows the band diagram of PEDOT:PSS/n-Si/ heterojunction hybrid solar cells. On the one hand, the hole-selective contact layer, PEDOT:PSS possesses a high work function of ~5.0 eV being greater than the electron affinity of the n-Si (4.05 eV), which builds an internal 8


Page 8 of 29

Page 9 of 29 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


electric field in the direction from n-Si to PEDOT:PSS, promoting the transport of holes. On the other hand, the electron-selective contact layer, the rubrene:DMSO film fabricated in this work, presents a low work function of 3.84 eV being lower than the electron affinity of the n-Si, which achieves a downward energy band bending, favoring majority carrier (electrons) transport and suppressing minority carrier (holes) recombination. Figure 3 shows the box diagram of the device PV performances based on different rear structure without (w/o) and with the rubrene:DMSO thin film layers. Box diagram offers a simple visual data summary. The scatter points show the values (minima, average and maxima) of the PV performance parameters and the length of the box diagram suggests the extent of uniform distribution of data. The smaller length of the box diagram indicates the more uniform device performance distribution. The values of open circuit voltage (Voc), short circuit current density (Jsc), fill factor (FF) and power conversion efficiency (PCE) are displayed in Table 1, with statistics based on three cells for each condition. The reference devices (w/o the rubrene:DMSO layer) achieve an average Voc of 562 mV, a Jsc of 28.8 mA/cm2 and a

FF of 58.1%, yielding a PCE of 9.4%. The PCE significantly increases when the electron-selective rubrene:DMSO contact layer is inserted between Ag and Si. It is observed that the device with 2 layer rubrene:DMSO films as electron-selective contact layer exhibits an average PCE of 11.9% and a maximum PCE of 12.1%. As the result of the low conductivity of the rubrene:DMSO thin film, the series resistance of the devices may get increased with the film layer increases, leading to the 9



Page 10 of 29

deteriorated device performance. In the following section, the comparison between the reference solar cell and the device with 2 layer rubrene:DMSO films will be discussed in details. As light management is not improved, Jsc does not substantially change between the devices with and w/o the rubrene:DMSO electron-selective contact layer.

Figure 3. The box diagram of PEDOT:PSS/Si heterojunction hybrid solar cells with different layers (0 layer (0L), 1L, 2L ,3L) of rubrene:DMSO thin film. Table 1. PV performance parameters of PEDOT:PSS/Si heterojunction hybrid solar cells with different layers of rubrene:DMSO thin film. Solar cells

Voc (mV)

Jsc (mA/cm2)

FF (%)

PCE (%)

w/o rubrene:DMSO

562±24

28.8±0.5

58.1±8.5

9.4±1.9

with 1L rubrene:DMSO

600±1

28.6±0.1

69.0±0.7

11.8±0.1


609±5

28.2±0.1

69.1±0.7

11.9±0.2


602±11

28.6±0.3

66.4±1.7

11.4±0.6

The internal physical mechanism of the PEDOT:PSS/Si heterojunction hybrid solar cells are evaluated by EIS, and the results of Nyquist plots are shown in Figure 4a. The diameter and the height of the semicircle dramatically change when a rubrene:DMSO thin film layer is inserted. This change is linked to impedance 10


Page 11 of 29 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


characteristics, including a series resistance (Rs), a recombination resistance (Rrec) and a junction capacitance (C), in the PEDOT:PSS/Si heterojunction hybrid solar cells. The impedance characteristics are fitted by the typical equivalent circuit model (see the inset in Figure 4a) and the establishment of hybrid solar cell’s equivalent circuit model can be seen elsewhere30. Table 2 shows the impedance characteristics of the devices. The device with the rubrene:DMSO thin film layer presents lower Rs of 6.6 Ω than the reference one without the rubrene:DMSO (16.8 Ω).This reduced Rs promotes the improvement of FF. Rrec of the PEDOT:PSS/Si heterojunction hybrid solar cells without and with rubrene:DMSO thin layer are 23.9 Ω and 195.2 Ω, respectively. The higher Rrec ensures the lower carrier recombination loss31.The minority carrier lifetime (τ) can be obtained from the equation (1) to quantitatively describe the carrier recombination rate. τ=Rrec×C

(1)

τ is found to be 1.2 ms for the reference device only with Ag electrode and 10.4 ms for the device with the rubrene:DMSO thin layer. This enhanced τ proves that the rubrene:DMSO thin layer reduces the carrier recombination rate. Here the τ values of the devices are relative values measured by EIS, which doesn’t represent the bulk lifetime of the Si wafer.

11



Page 12 of 29

Figure 4. (a) Nyquist plots of the PEDOT:PSS/Si heterojunction hybrid solar cells. The inset is the equivalent circuit model. (b) The Voc-decay curves of the PEDOT:PSS /Si heterojunction hybrid solar

cells.

(c)

The

PL

intensity

images

of

the

device

with

the

structure

PEDOT:PSS/Si/(rubrene:DMSO). Table 2. The impedance characteristics of PEDOT:PSS/Si heterojunction hybrid solar cells. Solar cells

Rs (Ω)

Rrec (kΩ)

C (F)

τ (ms)

16.8

23.9

5.2×10-8

1.2

6.6

195.2

5.3×10-8

10.4

w/o rubrene:DMSO with rubrene:DMSO

Figure 4b shows the Voc decay measurement of the PEDOT:PSS/Si heterojunction hybrid solar cells. In this measurement, the devices are initially illuminated under irradiation, when the light is switched off, Voc decay is observed due to carrier recombination. The decay rate is an indication of carrier lifetime. The device with the rubrene:DMSO thin layer exhibits a slower decay process than the reference one without the rubrene:DMSO. The slower decay process proves that the 12


Page 13 of 29 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


rubrene:DMSO thin film layer reduces the recombination rate again, which is agreement with the EIS results. Figure 4c shows the photoluminescence (PL) intensity image of the devices with the structure of PEDOT:PSS/Si/rubrene:DMSO. PL image provides spatial resolution of non-uniformities, crystal structures, grain boundaries, and localized defects32. PL is the optical radiation emitted by the Si bulk that results from band-to-band radiative recombination in the near-surface region33. PL intensity often correlates to carrier lifetime and solar cell’s performances. Bright regions correlate to higher PL intensity, which

is

proportional

to

carrier

lifetime.

The

PL

image

of

the

PEDOT:PSS/n-Si/rubrene:DMSO heterostructure shows higher intensity compared with the PEDOT:PSS/n-Si heterostructure，indicating the higher carrier lifetime in the structure with the rubrene:DMSO electron-selective contact layer. These results are consistent with the increased τ and the improved performance of the solar cells.

Figure 5 (a).Voc-scan of the PEDOT:PSS/Si/heterojunction hybrid solar cell w/o and with rubrene/DMSO thin layer. The size of the substrate is 10 mm×10 mm. (b) Rc-scan results of the devices with the structure PEDOT:PSS/Si/Ag and PEDOT:PSS/Si/rubrene:DMSO/Ag. The mapping area is 15 mm×15 mm. 13



Figure 5a shows the Voc spatial distribution of the PEDOT:PSS/Si/ heterojunction hybrid solar cells w/o and with the rubrene:DMSO thin layer as electron-selective contact, which was measured by Corescan tool. Corescan is an instrument to diagnosis the problems of the devices through different measurement modes34- 35. Here，two modes, namely Voc-scan (mapped by the distribution of Voc) and contact resistance (Rc)-scan, are adopted to measure the devices. The scanned Voc range of the reference solar cell is 540 ~ 560 mV, but that of the solar cell with the rubrene:DMSO thin layer is 560 ~ 600 mV. An obvious promotion of the Voc can be intuitively observed from the mapping image. As shown in Figure 5b, the Rc of the PEDOT:PSS/Si/Ag shows the wide range of 5~450 Ω, which shows non-uniform behavior, but that of the PEDOT:PSS/Si/rubrene:DMSO/Ag shows the tiny value range of 5~30 Ω, which shows very uniform behavior. Owing to the insertion of the rubrene:DMSO thin layer at the rear side of the device, the Voc and Rc are significantly improved.

4. Conclusion. The rubrene:DMSO organic small molecule thin film is fabricated by spin-coating. It is found that rubrene:DMSO thin film has a low work function, which is introduced into PEDOT:PSS/Si heterojunction hybrid solar cells as an efficient electron-selective contact, leading to an improvement in average PCE from 9.4% to 11.9%. This enhancement can be attributed to the low work function of the rubrene:DMSO thin layer, which could tailor energy band structures. Since the rubrene:DMSO thin layer is inserted between Si and Ag, the rear side energy band 14


Page 14 of 29

Page 15 of 29 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


achieves downward band bending, promoting the highly transparent of electrons and suppressing the recombination of the holes. This all-organic carrier-selective contact promises to revolutionize by providing inexpensive, lightweight and capable ubiquitous components that are coated onto ultrathin c-Si solar cells.

Acknowledgements. This work is supported by the Natural Science Foundation of Hebei Province (No. E2015201203, E2017201034, A2018201168，F2015201189), the “Advanced Talents Program of Hebei Province” (GCC2014013), the Top Young Outstanding Innovative Talents Program of Hebei Province (BJ2014009), the Midwest universities comprehensive strength promotion project (1060001010314), the “100 Talents Program of Hebei Province” (E2014100008) and the International Science and Technology Cooperation Project of China (2015DFE62900).

Author Information. Corresponding Authors *E-mail: [email protected] (Jianhui Chen.) *E-mail: [email protected] (Ying Xu) *E-mail: [email protected] (Yaohua Mai.) ORCID Jianhui Chen: 0000-0002-9875-354X Notes The authors declare no competing financial interest.

References. 15



1. Kim, E.-Y.; Kim, J. Effects of the Boron-Doped p+ Emitter on the Efficiency of the n-Type Silicon Solar Cell. Adv. Mater. Sci. Eng.2013, 1-6. 2. Zhao, L.; Wang, G.; Diao, H.; Wang, W. Physical Criteria for the Interface Passivation Layer in Hydrogenated Amorphous/Crystalline Silicon Heterojunction Solar Cell. J. Phys. D. Appl. Phys. 2018, 51 (4), 045501. 3. Bivour, M.; Macco, B.; Temmler, J.; Kessels, W. M. M.; Hermle, M. Atomic Layer Deposited Molybdenum Oxide for the Hole-Selective Contact of Silicon Solar Cells. Energy Procedia 2016, 92, 443-449. 4. Bivour, M.; Temmler, J.; Steinkemper, H.; Hermle, M. Molybdenum and Tungsten Oxide: High Work Function Wide Band Gap Contact Materials for Hole Selective Contacts of Silicon Solar Cells. Sol.Energ. Mat. Sol. C.2015, 142, 34-41. 5. Wu, S.; Cui, W.; Aghdassi, N.; Song, T.; Duhm, S.; Lee, S.-T.; Sun, B. Nanostructured Si/Organic Heterojunction Solar Cells with High Open-Circuit Voltage via Improving Junction Quality. Adv.Funct. Mater. 2016, 26 (28), 5035-5041. 6. Avasthi, S.; Lee,S.; Loo, Y. L.; Sturm, J. C. Role of Majority and Minority Carrier Barriers Silicon/Organic Hybrid Heterojunction Solar Cells. Adv. Mater.2011, 23 (48), 5762-6. 7. Zhang, F.T.; Sun,B.Q.; Song,T,; Zhu,X.L.; Lee,S. Air Stable, Efficient Hybrid Photovoltaic Devices Based on Poly(3-hexylthiophene) and Silicon Nanostructures. Chem. Mater. 2011, 23, 2084–2090. 8. Shinya, N.; Tatsuro, W.; Daisuke, N.;Tetsuro, H.;Yohei, Y.;Shintaro, K.; Kunihiko, N.; Hidetada, T.; Mikio, Y. Over 21% Efficiency of n-Type Monocrystalline Silicon 16


Page 16 of 29

Page 17 of 29 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


PERT Photovoltaic Cell with Boron Emitter. IEEE J. Photovolt.2016, 1-6. 9. Gatz, H. A.; Rath, J. K.; Verheijen, M. A.; Kessels, W. M. M.; Schropp, R. E. I. Silicon Heterojunction Solar Cell Passivation in Combination with Nanocrystalline Silicon Oxide Emitters. Phys. Status Solidi. A 2016, 213 (7), 1932-1936. 10. Bullock, J.; Wan, Y.; Xu, Z.; Essig, S.; Hettick, M.; Wang, H.; Ji, W.; Boccard, M.; Cuevas, A.; Ballif, C.; et al. Stable Dopant-Free Asymmetric Heterocontact Silicon Solar Cells with Efficiencies above 20%. ACS Energy Lett.2018, 3 (3), 508-513. 11. Bullock, J.; Hettick, M.; Geissbühler, J.; Ong, A. J.; Allen, T.; Sutter-Fella, Carolin M.; Chen, T.; Ota, H.; Schaler, E. W.; De Wolf, S.; et al. Efficient Silicon Solar Cells with Dopant-Free Asymmetric Heterocontacts. Nat. Energy 2016, 1 (3), 15031. 12. Huynh, W. U.; Dittmer, J. J.; Alivisatos, A. P. Hybrid Nanorod-Polymer Solar Cells. Science 2002, 295, 2425. 13. He, Jian. ; Gao, P.; Yang, Z.; Yu, J.; Yu, W.; Zhang, Y.; Sheng, J.; Ye, J.; Amine, J. C.; Cui, Y. Silicon/Organic Hybrid Solar Cells with 16.2% Efficiency and Improved Stability by Formation of Conformal Heterojunction Coating and Moisture-Resistant Capping Layer. Adv. Mater. 2017, 29, 1606321. 14. Zhang, Y.; Liu, R.; Lee, S.-T.; Sun, B. The Role of a LiF Layer on the Performance

of

Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate)/Si

Organic-Inorganic Hybrid Solar Cells. Appl. Phys. Lett. 2014, 104 (8), 083514. 15. Zhang, Y.; Cui, W.; Zhu, Y.; Zu, F.; Liao, L.; Lee, S.-T.; Sun, B. High Efficiency Hybrid PEDOT:PSS/Nanostructured Silicon Schottky Junction Solar Cells by 17



Page 18 of 29

Doping-Free Rear Contact. Energ. Environ. Sci.2015, 8 (1), 297-302. 16. Chen, B.; Chen, J.; Shen, Y.; Ge, K.; Guo, J.; Li, F.; Liu, H.; Xu, Y.; Mai, Y. Magnesium Thin Film as a Doping-Free Back Surface Field Layer for Hybrid Solar Cells. Appl. Phys. Lett. 2017, 110 (13), 133504. 17. Ge, K.; Chen, J.; Chen, B.; Shen, Y.; Guo, J.; Li, F.; Liu, H.; Xu, Y.; Mai, Y. Low Work Function Intermetallic Thin Film as a Back Surface Field Material for Hybrid Solar Cells. Sol. Energy 2018, 162, 397-402. 18. Liu, Y.; Zhang, J.; Wu, H.; Cui, W.; Wang, R.; Ding, K.; Lee, S.-T.; Sun, B. Low-Temperature

Synthesis

TiOx

Passivation

Layer

for

Organic-Silicon

Heterojunction Solar Cell with a High Open-Circuit Voltage. Nano Energy 2017, 34, 257-263. 19. Tong, H.; Yang, Z.; Wang, X.; Liu, Z.; Chen, Z.; Ke, X.; Sui, M.; Tang, J.; Yu, T.; Ge, Z.; et al. Dual Functional Electron-Selective Contacts Based on Silicon Oxide/Magnesium: Tailoring Heterointerface Band Structures while Maintaining Surface Passivation. Adv. Energy Mater.2018, 1702921. 20. Zhang, Y.; Zu, F.; Lee, S.-T.; Liao, L.; Zhao, N.; Sun, B. Heterojunction with Organic Thin Layers on Silicon for Record Efficiency Hybrid Solar Cells. Adv. Energy. Mater.2014, 4 (2), 1300923. 21. Han, Y.; Liu, Y.; Yuan, J.; Dong, H.; Li, Y.; Ma, W.; Lee, S. T.; Sun, B. Naphthalene Diimide-Based n-Type Polymers: Efficient Rear Interlayers for High-Performance Silicon-Organic Heterojunction Solar Cells. ACS Nano 2017, 11 (7), 7215-7222. 18


Page 19 of 29 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


22. Barış, B.; Özdemir, H. G.; Tuğluoğlu, N.; Karadeniz, S.; Yüksel, Ö. F.; Kişnişci, Z. Optical Dispersion and Dielectric Properties of Rubrene Organic Semiconductor Thin Film. J. Mater. Sci-Mater. El. 2014, 25 (8), 3586-3593. 23. Yoon, Y.; Kim, S.; Lee, H.; Kim, T.; Babajanyan, A.; Lee, K.; Friedman, B. Characterization of Rubrene Polycrystalline Thin Film Transistors Fabricated using Various Heat-Treatment Conditions. Thin Solid Films 2011, 519 (16), 5562-5566. 24. Hsu, C. H.; Deng, J.; Staddon, C. R.; Beton, P. H. Growth Front Nucleation of Rubrene Thin Films for High Mobility Organic Transistors. Appl. Phys. Lett.2007, 91 (19), 193505. 25. Kim, K.; Kim, M. K.; Kang, H. S.; Cho, M. Y.; Joo, J.; Kim, J. H.; Kim, K. H.; Hong, C. S.; Choi, D. H. New Growth Method of Rubrene Single Crystal for Organic Field-Effect Transistor. Synthetic Met.2007, 157 (10-12), 481-484. 26. Choukri, H.; Fischer, A.; Forget, S.; Chénais, S.; Castex, M.-C.; Adès, D.; Siove, A.; Geffroy, B. White Organic Light-Emitting Diodes with Fine Chromaticity Tuning via Ultrathin Layer Position Shifting. Appl. Phys. Lett.2006, 89 (18), 183513. 27. Sinha, S.; Mukherjee, M. A Comparative Study about Electronic Structures at Rubrene/Ag and Ag/Rubrene Interfaces. AIP Adv. 2015, 5 (10), 107204. 28. Koylu, D.; Sarrafpour, S.; Zhang, J.; Ramjattan, S.; Panzer, M. J.; Thomas, S. W. A Cene-Doped Polymer Films: Singlet Oxygen Dosimetry and Protein Sensing. Chem.Commun. 2012, 48 (76), 9489-91. 29. Derouiche, H.; Djara, V.; Impact of the Energy Difference in LUMO and HOMO of the Bulk Heterojunctions Components on the Efficiency of Organic Solar Cells. Sol. 19



Energ. Mat. Sol. C. 2007, 91(13),1163-1167. 30. Wang, D.; Zhu, J.; Ding, L.; Gao, P.; Pan, X.; Sheng, J.; Ye, J. Interface Electric Properties of Si/Organic Hybrid Solar Cells using Impedance Spectroscopy Analysis. Jap. J. Appl. Phys.2016, 55 (5), 056601. 31. Nam, Y. H.; Song, J. W.; Park, M. J.; Sami, A.; Lee, J. H. Ultrathin Al2O3 Interface Achieving an 11.46% Efficiency in Planar n-Si/PEDOT:PSS Hybrid Solar Cells. Nanotechnology 2017, 28 (15), 155402. 32. Johnston, S.; Motz, A. A.; Moore, J. C.; Zheng, M.; Javey, A.; Bermel, P. Photoluminescence Imaging Characterization of Thin-Film InP. Photovoltaic Specialists Conference 2015, 1-6. 33. Chen, J.; Yang, L.; Ge, K.; Chen, B.; Shen, Y.; Guo, J.; Liu, H.; Xu, Y.; Fan, J.; Mai, Y. On the Light-Induced Enhancement in Photovoltaic Performance of PEDOT:PSS/Si Organic-Inorganic Hybrid Solar Cells. Appl. Phys. Lett. 2017, 111 (18), 183904. 34. Van der Heide, A.S.H.; Bultman, J.H.; Hoornstra, J.; Schönecker, A. Contact Resistances Measured using the Corescan: Relations with Cell Processing.17th European Photovoltaic Solar Energy Conference, Munich, Germany, 2001. 35. van der Heide, A. S. H.; Schönecker, A.; Bultman, J. H.; Sinke, W. C. Explanation of High Solar Cell Diode Factors by Nonuniform Contact Resistance. Prog. Photovoltaics: Res. Appl. 2005, 13 (1), 3-16.

20


Page 20 of 29

Page 21 of 29 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


TOC Graphic

TOC Graphic

21



251x166mm (300 x 300 DPI)


Page 22 of 29

Page 23 of 29 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


224x97mm (300 x 300 DPI)



268x190mm (300 x 300 DPI)


Page 24 of 29

Page 25 of 29 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


272x191mm (300 x 300 DPI)



169x149mm (300 x 300 DPI)


Page 26 of 29

Page 27 of 29 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


225x120mm (300 x 300 DPI)



216x100mm (300 x 300 DPI)


Page 28 of 29

Page 29 of 29 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


315x139mm (300 x 300 DPI)


Si Heterojunction Hybrid Solar Cells with Rubrene:DMSO

Recommend Documents