Processing Dependent Influence of the Hole Transport Layer Ionization Energy on Methylammonium Lead Iodide Perovskite Photovoltaics

Park, So Min; Mazza, Samuel M.; Liang, Zhiming; Abtahi, Ashkan; Boehm, Alex M.; Parkin, Sean R.; Anthony, John E.; Graham, Kenneth R.

doi:10.1021/acsami.7b16894

Title: Processing Dependent Influence of the Hole Transport Layer Ionization Energy on Methylammonium Lead Iodide Perovskite Photovoltaics

Journal Article · Thu Apr 19 00:00:00 EDT 2018 · ACS Applied Materials and Interfaces

DOI:https://doi.org/10.1021/acsami.7b16894· OSTI ID:1594897

Park, So Min ^[1]; Mazza, Samuel M. ^[1]; Liang, Zhiming ^[1]; Abtahi, Ashkan ^[1]; Boehm, Alex M. ^[1]; Parkin, Sean R. ^[1];

^[1];

^[1]

Univ. of Kentucky, Lexington, KY (United States)

Organometal halide perovskite photovoltaics typically contain both electron and hole transport layers, both of which influence charge extraction and recombination. The ionization energy (IE) of the hole transport layer (HTL) is one important material property that will influence the open-circuit voltage, fill factor, and short-circuit current. Herein, we introduce a new series of triarylaminoethynylsilanes with adjustable IEs as efficient HTL materials for methylammonium lead iodide (MAPbI₃) perovskite based photovoltaics. The three triarylaminoethynylsilanes investigated can all be used as HTLs to yield PV performance on par with the commonly used HTLs PEDOT:PSS and Spiro-OMeTAD in inverted architectures (i.e., HTL deposited prior to the perovskite layer). We further investigate the influence of the HTL IE on the photovoltaic performance of MAPbI₃ based inverted devices using two different MAPbI₃ processing methods with a series of 11 different HTL materials, with IEs ranging from 4.74 to 5.84 eV. The requirements for the HTL IE change based on whether MAPbI₃ is formed from lead acetate, Pb(OAc)₂, or PbI₂ as the Pb source. The ideal HTL IE range is between 4.8 and 5.3 eV for MAPbI₃ processed from Pb(OAc)₂, while with PbI₂ the PV performance is relatively insensitive to variations in the HTL IE between 4.8 and 5.8 eV. Finally, our results suggest that contradictory findings in the literature on the effect of the HTL IE in perovskite photovoltaics stem partly from the different processing methods employed.

View Accepted Manuscript (DOE)

Cite

Export

Save

Research Organization:: Univ. of Kentucky, Lexington, KY (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)

Grant/Contract Number:: SC0018208; 1609974; CHE-0319176

OSTI ID:: 1594897

Journal Information:: ACS Applied Materials and Interfaces, Vol. 10, Issue 18; ISSN 1944-8244

Publisher:: American Chemical Society (ACS)Copyright Statement

Country of Publication:: United States

Language:: English

Citation Metrics:

Cited by: 18 works

Citation information provided by
Web of Science

References (63)

Organometal Halide Perovskites as Visible-Light Sensitizers for Photovoltaic Cells Kojima, Akihiro; Teshima, Kenjiro; Shirai, Yasuo Journal of the American Chemical Society, Vol. 131, Issue 17, p. 6050-6051 https://doi.org/10.1021/ja809598r	journal	May 2009
Polymer-templated nucleation and crystal growth of perovskite films for solar cells with efficiency greater than 21% Bi, Dongqin; Yi, Chenyi; Luo, Jingshan Nature Energy, Vol. 1, Issue 10 https://doi.org/10.1038/nenergy.2016.142	journal	September 2016
Iodide management in formamidinium-lead-halide–based perovskite layers for efficient solar cells Yang, Woon Seok; Park, Byung-Wook; Jung, Eui Hyuk Science, Vol. 356, Issue 6345 https://doi.org/10.1126/science.aan2301	journal	June 2017
High-performance photovoltaic perovskite layers fabricated through intramolecular exchange Yang, W. S.; Noh, J. H.; Jeon, N. J. Science, Vol. 348, Issue 6240 https://doi.org/10.1126/science.aaa9272	journal	May 2015
Origin and elimination of photocurrent hysteresis by fullerene passivation in CH3NH3PbI3 planar heterojunction solar cells Shao, Yuchuan; Xiao, Zhengguo; Bi, Cheng Nature Communications, Vol. 5, Issue 1 https://doi.org/10.1038/ncomms6784	journal	December 2014
Dual function interfacial layer for highly efficient and stable lead halide perovskite solar cells Song, Dandan; Wei, Dong; Cui, Peng Journal of Materials Chemistry A, Vol. 4, Issue 16 https://doi.org/10.1039/C6TA00577B	journal	January 2016
Hole-transport material variation in fully vacuum deposited perovskite solar cells Polander, Lauren E.; Pahner, Paul; Schwarze, Martin APL Materials, Vol. 2, Issue 8 https://doi.org/10.1063/1.4889843	journal	August 2014
Molecularly Engineered Phthalocyanines as Hole-Transporting Materials in Perovskite Solar Cells Reaching Power Conversion Efficiency of 17.5% Cho, Kyung Teak; Trukhina, Olga; Roldán-Carmona, Cristina Advanced Energy Materials, Vol. 7, Issue 7 https://doi.org/10.1002/aenm.201601733	journal	December 2016
Carbazole-Based Hole-Transport Materials for Efficient Solid-State Dye-Sensitized Solar Cells and Perovskite Solar Cells Xu, Bo; Sheibani, Esmaeil; Liu, Peng Advanced Materials, Vol. 26, Issue 38 https://doi.org/10.1002/adma.201402415	journal	August 2014
Phenoxazine-Based Small Molecule Material for Efficient Perovskite Solar Cells and Bulk Heterojunction Organic Solar Cells Cheng, Ming; Xu, Bo; Chen, Cheng Advanced Energy Materials, Vol. 5, Issue 8 https://doi.org/10.1002/aenm.201401720	journal	January 2015
Decoupling Charge Transfer and Transport at Polymeric Hole Transport Layer in Perovskite Solar Cells Sin, Dong Hun; Ko, Hyomin; Jo, Sae Byeok ACS Applied Materials & Interfaces, Vol. 8, Issue 10 https://doi.org/10.1021/acsami.5b12023	journal	March 2016
Pinhole-free hole transport layers significantly improve the stability of MAPbI ₃ -based perovskite solar cells under operating conditions Ono, Luis K.; Raga, Sonia R.; Remeika, Mikas Journal of Materials Chemistry A, Vol. 3, Issue 30 https://doi.org/10.1039/C5TA03443D	journal	January 2015
Dopant-Free Hole Transporting Polymers for High Efficiency, Environmentally Stable Perovskite Solar Cells Liao, Hsueh-Chung; Tam, Teck Lip Dexter; Guo, Peijun Advanced Energy Materials, Vol. 6, Issue 16 https://doi.org/10.1002/aenm.201600502	journal	June 2016
Fulleropyrrolidinium Iodide As an Efficient Electron Transport Layer for Air-Stable Planar Perovskite Solar Cells Huang, Jiabin; Yu, Xuegong; Xie, Jiangsheng ACS Applied Materials & Interfaces, Vol. 8, Issue 50 https://doi.org/10.1021/acsami.6b08771	journal	December 2016
Highly Efficient Organic Hole Transporting Materials for Perovskite and Organic Solar Cells with Long-Term Stability Reddy, Saripally Sudhaker; Gunasekar, Kumarasamy; Heo, Jin Hyuck Advanced Materials, Vol. 28, Issue 4 https://doi.org/10.1002/adma.201503729	journal	November 2015
Recent Progress on Hole-Transporting Materials for Emerging Organometal Halide Perovskite Solar Cells Yu, Ze; Sun, Licheng Advanced Energy Materials, Vol. 5, Issue 12 https://doi.org/10.1002/aenm.201500213	journal	April 2015
High-Performance and Environmentally Stable Planar Heterojunction Perovskite Solar Cells Based on a Solution-Processed Copper-Doped Nickel Oxide Hole-Transporting Layer Kim, Jong H.; Liang, Po-Wei; Williams, Spencer T. Advanced Materials, Vol. 27, Issue 4 https://doi.org/10.1002/adma.201404189	journal	November 2014
Investigation of CH ₃ NH ₃ PbI ₃ Degradation Rates and Mechanisms in Controlled Humidity Environments Using in Situ Techniques Yang, Jinli; Siempelkamp, Braden D.; Liu, Dianyi ACS Nano, Vol. 9, Issue 2 https://doi.org/10.1021/nn506864k	journal	January 2015
Degradation observations of encapsulated planar CH ₃ NH ₃ PbI ₃ perovskite solar cells at high temperatures and humidity Han, Yu; Meyer, Steffen; Dkhissi, Yasmina Journal of Materials Chemistry A, Vol. 3, Issue 15 https://doi.org/10.1039/C5TA00358J	journal	January 2015
Improved air stability of perovskite solar cells via solution-processed metal oxide transport layers You, Jingbi; Meng, Lei; Song, Tze-Bin Nature Nanotechnology, Vol. 11, Issue 1 https://doi.org/10.1038/nnano.2015.230	journal	October 2015
Strategy to Boost the Efficiency of Mixed-Ion Perovskite Solar Cells: Changing Geometry of the Hole Transporting Material Zhang, Jinbao; Xu, Bo; Johansson, Malin B. ACS Nano, Vol. 10, Issue 7 https://doi.org/10.1021/acsnano.6b02442	journal	June 2016
Triarylamine: Versatile Platform for Organic, Dye-Sensitized, and Perovskite Solar Cells Wang, Jiayu; Liu, Kuan; Ma, Lanchao Chemical Reviews, Vol. 116, Issue 23 https://doi.org/10.1021/acs.chemrev.6b00432	journal	November 2016
14.8% perovskite solar cells employing carbazole derivatives as hole transporting materials Sung, Sang Do; Kang, Min Soo; Choi, In Taek Chem. Commun., Vol. 50, Issue 91 https://doi.org/10.1039/C4CC06716A	journal	January 2014
Novel Carbazole-Based Hole-Transporting Materials with Star-Shaped Chemical Structures for Perovskite-Sensitized Solar Cells Kang, Min Soo; Sung, Sang Do; Choi, In Taek ACS Applied Materials & Interfaces, Vol. 7, Issue 40 https://doi.org/10.1021/acsami.5b04662	journal	September 2015
Facile Synthesis and High Performance of a New Carbazole-Based Hole-Transporting Material for Hybrid Perovskite Solar Cells Wang, Hong; Sheikh, Arif D.; Feng, Quanyou ACS Photonics, Vol. 2, Issue 7 https://doi.org/10.1021/acsphotonics.5b00283	journal	July 2015
High-Performance Long-Term-Stable Dopant-Free Perovskite Solar Cells and Additive-Free Organic Solar Cells by Employing Newly Designed Multirole π-Conjugated Polymers Kranthiraja, Kakaraparthi; Gunasekar, Kumarasamy; Kim, Hyunji Advanced Materials, Vol. 29, Issue 23 https://doi.org/10.1002/adma.201700183	journal	April 2017
Non-wetting surface-driven high-aspect-ratio crystalline grain growth for efficient hybrid perovskite solar cells Bi, Cheng; Wang, Qi; Shao, Yuchuan Nature Communications, Vol. 6, Issue 1 https://doi.org/10.1038/ncomms8747	journal	July 2015
Solvent engineering for high-performance inorganic–organic hybrid perovskite solar cells Jeon, Nam Joong; Noh, Jun Hong; Kim, Young Chan Nature Materials, Vol. 13, Issue 9, p. 897-903 https://doi.org/10.1038/nmat4014	journal	July 2014
Polyelectrolyte based hole-transporting materials for high performance solution processed planar perovskite solar cells Li, Xiaodong; Liu, Xiaohui; Wang, Xueyan Journal of Materials Chemistry A, Vol. 3, Issue 29 https://doi.org/10.1039/C5TA04712A	journal	January 2015
Conjugated polyelectrolyte hole transport layer for inverted-type perovskite solar cells Choi, Hyosung; Mai, Cheng-Kang; Kim, Hak-Beom Nature Communications, Vol. 6, Issue 1 https://doi.org/10.1038/ncomms8348	journal	June 2015
p-i-n/n-i-p type planar hybrid structure of highly efficient perovskite solar cells towards improved air stability: synthetic strategies and the role of p-type hole transport layer (HTL) and n-type electron transport layer (ETL) metal oxides Mali, Sawanta S.; Hong, Chang Kook Nanoscale, Vol. 8, Issue 20 https://doi.org/10.1039/C6NR02276F	journal	January 2016
Minimal Effect of the Hole-Transport Material Ionization Potential on the Open-Circuit Voltage of Perovskite Solar Cells Belisle, Rebecca A.; Jain, Pratham; Prasanna, Rohit ACS Energy Letters, Vol. 1, Issue 3 https://doi.org/10.1021/acsenergylett.6b00270	journal	August 2016
Quantifying Hole Transfer Yield from Perovskite to Polymer Layer: Statistical Correlation of Solar Cell Outputs with Kinetic and Energetic Properties Ishida, Naoki; Wakamiya, Atsushi; Saeki, Akinori ACS Photonics, Vol. 3, Issue 9 https://doi.org/10.1021/acsphotonics.6b00331	journal	July 2016
Gradated Mixed Hole Transport Layer in a Perovskite Solar Cell: Improving Moisture Stability and Efficiency Kim, Guan-Woo; Kang, Gyeongho; Malekshahi Byranvand, Mahdi ACS Applied Materials & Interfaces, Vol. 9, Issue 33 https://doi.org/10.1021/acsami.7b07071	journal	August 2017
Triazatruxene-Based Hole Transporting Materials for Highly Efficient Perovskite Solar Cells Rakstys, Kasparas; Abate, Antonio; Dar, M. Ibrahim Journal of the American Chemical Society, Vol. 137, Issue 51 https://doi.org/10.1021/jacs.5b11076	journal	December 2015
Synthesis and spectroscopic study of diphenylamino-substituted phenylene-(poly)ethynylenes: remarkable effect of acetylenic conjugation modes Fang, Jing-Kun; An, De-Lie; Wakamatsu, Kan Tetrahedron Letters, Vol. 51, Issue 6 https://doi.org/10.1016/j.tetlet.2009.12.023	journal	February 2010
Diacetylene bridged triphenylamines as hole transport materials for solid state dye sensitized solar cells Planells, Miquel; Abate, Antonio; Hollman, Derek J. Journal of Materials Chemistry A, Vol. 1, Issue 23 https://doi.org/10.1039/c3ta11417a	journal	January 2013
A new photon source for ultraviolet photoelectron spectroscopy of organic and other damage-prone materials Boehm, Alex M.; Wieser, Jochen; Butrouna, Kamal Organic Electronics, Vol. 41 https://doi.org/10.1016/j.orgel.2016.11.032	journal	February 2017
Synthesis, Morphology, and Field-Effect Mobility of Anthradithiophenes Laquindanum, Joyce G.; Katz, Howard E.; Lovinger, Andrew J. Journal of the American Chemical Society, Vol. 120, Issue 4 https://doi.org/10.1021/ja9728381	journal	February 1998
Interface energetics in organo-metal halide perovskite-based photovoltaic cells Schulz, Philip; Edri, Eran; Kirmayer, Saar Energy & Environmental Science, Vol. 7, Issue 4 https://doi.org/10.1039/c4ee00168k	journal	January 2014
Substrate-controlled band positions in CH ₃ NH ₃ PbI ₃ perovskite films Miller, Elisa M.; Zhao, Yixin; Mercado, Candy C. Phys. Chem. Chem. Phys., Vol. 16, Issue 40 https://doi.org/10.1039/C4CP03533J	journal	January 2014
Electronic Structures and Photoconversion Mechanism in Perovskite/Fullerene Heterojunctions Lo, Ming-Fai; Guan, Zhi-Qiang; Ng, Tsz-Wai Advanced Functional Materials, Vol. 25, Issue 8 https://doi.org/10.1002/adfm.201402692	journal	December 2014
Valence and Conduction Band Densities of States of Metal Halide Perovskites: A Combined Experimental–Theoretical Study Endres, James; Egger, David A.; Kulbak, Michael The Journal of Physical Chemistry Letters, Vol. 7, Issue 14 https://doi.org/10.1021/acs.jpclett.6b00946	journal	June 2016
Probing the energy levels of perovskite solar cells via Kelvin probe and UV ambient pressure photoemission spectroscopy Harwell, J. R.; Baikie, T. K.; Baikie, I. D. Physical Chemistry Chemical Physics, Vol. 18, Issue 29 https://doi.org/10.1039/C6CP02446G	journal	January 2016
Halide-Substituted Electronic Properties of Organometal Halide Perovskite Films: Direct and Inverse Photoemission Studies Li, Chi; Wei, Jian; Sato, Mikio ACS Applied Materials & Interfaces, Vol. 8, Issue 18 https://doi.org/10.1021/acsami.6b02692	journal	April 2016
Stability of Organic Cations in Solution-Processed CH ₃ NH ₃ PbI ₃ Perovskites: Formation of Modified Surface Layers Calloni, A.; Abate, A.; Bussetti, G. The Journal of Physical Chemistry C, Vol. 119, Issue 37 https://doi.org/10.1021/acs.jpcc.5b05422	journal	September 2015
Research Update: The electronic structure of hybrid perovskite layers and their energetic alignment in devices Olthof, Selina APL Materials, Vol. 4, Issue 9 https://doi.org/10.1063/1.4960112	journal	August 2016
Dopant interdiffusion effects in n-i-p structured spiro-OMeTAD hole transport layer of organometal halide perovskite solar cells Jung, Min-Cherl; Qi, Yabing Organic Electronics, Vol. 31 https://doi.org/10.1016/j.orgel.2016.01.018	journal	April 2016
The Roles of Structural Order and Intermolecular Interactions in Determining Ionization Energies and Charge-Transfer State Energies in Organic Semiconductors Graham, Kenneth R.; Ndjawa, Guy O. Ngongang; Conron, Sarah M. Advanced Energy Materials, Vol. 6, Issue 22 https://doi.org/10.1002/aenm.201601211	journal	August 2016
Determination of Energy Level Alignment within an Energy Cascade Organic Solar Cell Endres, James; Pelczer, István; Rand, Barry P. Chemistry of Materials, Vol. 28, Issue 3 https://doi.org/10.1021/acs.chemmater.5b03857	journal	January 2016
Low-Energy Inverse Photoemission Study on the Electron Affinities of Fullerene Derivatives for Organic Photovoltaic Cells Yoshida, Hiroyuki The Journal of Physical Chemistry C, Vol. 118, Issue 42 https://doi.org/10.1021/jp509141y	journal	October 2014
4-Hydroxy-8-methyl-1,5-naphthyridine aluminium chelate: a morphologically stable and efficient exciton-blocking material for organic photovoltaics with prolonged lifetime Liu, Shun-Wei; Lee, Chih-Chien; Lin, Chi-Feng Journal of Materials Chemistry, Vol. 20, Issue 36 https://doi.org/10.1039/c0jm01049a	journal	January 2010
Energy level tuning of blue emitting and electron transporting vinylene bis(vinyl quinolinyl)benzene derivatives: synthesis, characterisation, thin film characterisation and performance in OLEDs Kathirgamanathan, Poopathy; Surendrakumar, Sivagnanasundram; Ravichandran, Seenivasagam Journal of Materials Chemistry C, Vol. 3, Issue 26 https://doi.org/10.1039/C5TC00932D	journal	January 2015
High-Performance Inverted Planar Heterojunction Perovskite Solar Cells Based on Lead Acetate Precursor with Efficiency Exceeding 18% Zhao, Lichen; Luo, Deying; Wu, Jiang Advanced Functional Materials, Vol. 26, Issue 20 https://doi.org/10.1002/adfm.201601175	journal	April 2016
Effect of mobility and band structure of hole transport layer in planar heterojunction perovskite solar cells using 2D TCAD simulation Alnuaimi, Aaesha; Almansouri, Ibraheem; Nayfeh, Ammar Journal of Computational Electronics, Vol. 15, Issue 3 https://doi.org/10.1007/s10825-016-0850-1	journal	July 2016
A diketopyrrolopyrrole-containing hole transporting conjugated polymer for use in efficient stable organic–inorganic hybrid solar cells based on a perovskite Kwon, Young Soo; Lim, Jongchul; Yun, Hui-Jun Energy & Environmental Science, Vol. 7, Issue 4 https://doi.org/10.1039/c3ee44174a	journal	January 2014
Substrate-dependent electronic structure and film formation of MAPbI3 perovskites Olthof, Selina; Meerholz, Klaus Scientific Reports, Vol. 7, Issue 1 https://doi.org/10.1038/srep40267	journal	January 2017
Impact of Film Stoichiometry on the Ionization Energy and Electronic Structure of CH ₃ NH ₃ PbI ₃ Perovskites Emara, Jennifer; Schnier, Tobias; Pourdavoud, Neda Advanced Materials, Vol. 28, Issue 3 https://doi.org/10.1002/adma.201503406	journal	November 2015
Intrinsic Transport Properties and Performance Limits of Organic Field-Effect Transistors Torsi, L.; Dodabalapur, A.; Rothberg, L. J. Science, Vol. 272, Issue 5267 https://doi.org/10.1126/science.272.5267.1462	journal	June 1996
Nondispersive hole transport in amorphous films of methoxy-spirofluorene-arylamine organic compound Poplavskyy, Dmitry; Nelson, Jenny Journal of Applied Physics, Vol. 93, Issue 1 https://doi.org/10.1063/1.1525866	journal	January 2003
Interface and Composition Analysis on Perovskite Solar Cells Matteocci, Fabio; Busby, Yan; Pireaux, Jean-Jacques ACS Applied Materials & Interfaces, Vol. 7, Issue 47 https://doi.org/10.1021/acsami.5b08038	journal	November 2015
Mobile-Ion-Induced Degradation of Organic Hole-Selective Layers in Perovskite Solar Cells Zhao, Yicheng; Zhou, Wenke; Tan, Hairen The Journal of Physical Chemistry C, Vol. 121, Issue 27 https://doi.org/10.1021/acs.jpcc.7b04684	journal	June 2017
Redox Chemistry Dominates the Degradation and Decomposition of Metal Halide Perovskite Optoelectronic Devices Zhao, Lianfeng; Kerner, Ross A.; Xiao, Zhengguo ACS Energy Letters, Vol. 1, Issue 3 https://doi.org/10.1021/acsenergylett.6b00320	journal	August 2016

Cited By (1)

Electronic structure of MAPbI3 and MAPbCl3: importance of band alignment Caputo, Marco; Cefarin, Nicola; Radivo, Andrea Scientific Reports, Vol. 9, Issue 1 https://doi.org/10.1038/s41598-019-50108-0	journal	October 2019

Linked Research (3)

Similar Records

Band Tailing and Deep Defect States in CH₃NH₃Pb(I_1–xBr_x)₃ Perovskites As Revealed by Sub-Bandgap Photocurrent

Journal Article · Wed Feb 15 00:00:00 EST 2017 · ACS Energy Letters · OSTI ID:1594897

Sutter-Fella, Carolin M.; Miller, D. Westley; Ngo, Quynh P.; +5 more

Interfacial Connections between Organic Perovskite/n ⁺ Silicon/Catalyst that Allow Integration of Solar Cell and Catalyst for Hydrogen Evolution from Water

Journal Article · Wed Mar 15 00:00:00 EDT 2023 · Advanced Functional Materials · OSTI ID:1594897

Gu, Hengfei; Zhang, Fei; Hwang, Shinjae; +19 more

Modulation of PEDOT:PSS pH for efficient inverted perovskite solar cells with reduced potential loss and enhanced stability

Journal Article · Wed Nov 02 00:00:00 EDT 2016 · ACS Applied Materials and Interfaces · OSTI ID:1594897

Wang, Qin; Chueh, Chu -Chen; Eslamian, Morteza; +1 more

Related Subjects

36 MATERIALS SCIENCE
organometal halide perovskite
photovoltaic
photoelectron spectroscopy
processing
hole transport layer

CCDC 1527224: Experimental Crystal Structure Determination Park, So Min; Mazza, Samuel M.; Liang, Zhiming https://doi.org/10.5517/ccdc.csd.cc1n869f The current record is supplemented by this dataset	dataset	January 2018
CCDC 1527222: Experimental Crystal Structure Determination Park, So Min; Mazza, Samuel M.; Liang, Zhiming https://doi.org/10.5517/ccdc.csd.cc1n867c The current record is supplemented by this dataset	dataset	January 2018
CCDC 1527223: Experimental Crystal Structure Determination Park, So Min; Mazza, Samuel M.; Liang, Zhiming https://doi.org/10.5517/ccdc.csd.cc1n868d The current record is supplemented by this dataset	dataset	January 2018