Hirotaka Kojima

1.4k total citations
39 papers, 1.2k citations indexed

About

Hirotaka Kojima is a scholar working on Electrical and Electronic Engineering, Materials Chemistry and Electronic, Optical and Magnetic Materials. According to data from OpenAlex, Hirotaka Kojima has authored 39 papers receiving a total of 1.2k indexed citations (citations by other indexed papers that have themselves been cited), including 21 papers in Electrical and Electronic Engineering, 12 papers in Materials Chemistry and 9 papers in Electronic, Optical and Magnetic Materials. Recurrent topics in Hirotaka Kojima's work include Organic Electronics and Photovoltaics (11 papers), Perovskite Materials and Applications (6 papers) and Conducting polymers and applications (6 papers). Hirotaka Kojima is often cited by papers focused on Organic Electronics and Photovoltaics (11 papers), Perovskite Materials and Applications (6 papers) and Conducting polymers and applications (6 papers). Hirotaka Kojima collaborates with scholars based in Japan, United States and Germany. Hirotaka Kojima's co-authors include Takehiko Mori, Masakazu Nakamura, Jun Sawai, Mitsuhiro Ito, M. Shimizu, Hideo Igarashi, Takao Kokugan, Takeshi Saito, Takuya Koizumi and Shusaku Shoji and has published in prestigious journals such as Nature Communications, The Journal of Chemical Physics and Applied Physics Letters.

In The Last Decade

Hirotaka Kojima

37 papers receiving 1.1k citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Hirotaka Kojima Japan 20 579 400 287 188 179 39 1.2k
Sun Hye Hwang South Korea 17 825 1.4× 370 0.9× 287 1.0× 150 0.8× 194 1.1× 28 1.5k
Emmanuel Ν. Koukaras Greece 24 999 1.7× 638 1.6× 287 1.0× 113 0.6× 472 2.6× 94 2.0k
Paweł Niedziałkowski Poland 22 405 0.7× 582 1.5× 396 1.4× 100 0.5× 134 0.7× 75 1.4k
Arnab Ghosh India 21 888 1.5× 696 1.7× 330 1.1× 350 1.9× 143 0.8× 50 1.6k
Chunmei Zhao China 21 635 1.1× 372 0.9× 526 1.8× 427 2.3× 146 0.8× 56 1.9k
J. A. Balderas‐López Mexico 20 324 0.6× 215 0.5× 543 1.9× 91 0.5× 132 0.7× 68 1.1k
Чан Лю China 20 719 1.2× 315 0.8× 223 0.8× 149 0.8× 182 1.0× 61 1.2k
Yanjing Liu China 16 380 0.7× 672 1.7× 260 0.9× 130 0.7× 133 0.7× 58 1.3k
Zhengwei Xiong China 21 655 1.1× 368 0.9× 296 1.0× 416 2.2× 145 0.8× 94 1.4k
Wenfang Wang China 18 483 0.8× 212 0.5× 233 0.8× 134 0.7× 114 0.6× 50 926

Countries citing papers authored by Hirotaka Kojima

Since Specialization
Citations

This map shows the geographic impact of Hirotaka Kojima's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Hirotaka Kojima with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Hirotaka Kojima more than expected).

Fields of papers citing papers by Hirotaka Kojima

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Hirotaka Kojima. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Hirotaka Kojima. The network helps show where Hirotaka Kojima may publish in the future.

Co-authorship network of co-authors of Hirotaka Kojima

This figure shows the co-authorship network connecting the top 25 collaborators of Hirotaka Kojima. A scholar is included among the top collaborators of Hirotaka Kojima based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Hirotaka Kojima. Hirotaka Kojima is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Kadoya, Tomofumi, Teppei Imai, Hiroki Sano, et al.. (2025). Benzothienobenzothiophene: recent uses as a transistor material and derivatization for adding new features in device functions. CrystEngComm. 27(47). 7601–7614.
2.
Nakamura, Masakazu, et al.. (2023). Giant Seebeck effect over 0.1 V K−1 – is this an intrinsic phenomenon in organic semiconductors?. Faraday Discussions. 250(0). 361–376. 3 indexed citations
3.
Hiroshiba, Nobuya, et al.. (2023). Early Stage Growth Process of Dinaphtho[2,3‐b:2',3'‐f]thieno[3,2‐b]thiophene (DNTT) Thin Film. physica status solidi (a). 220(24).
4.
Hiroshiba, Nobuya, et al.. (2023). Early Stage Growth Process of Dinaphtho[2,3‐b:2',3'‐f]thieno[3,2‐b]thiophene (DNTT) Thin Film. physica status solidi (a). 220(24). 1 indexed citations
5.
Kojima, Hirotaka, et al.. (2023). Error factors in precise thermal conductivity measurement using 3ω method for wire samples. Journal of Thermal Analysis and Calorimetry. 148(6). 2285–2296. 8 indexed citations
6.
Kojima, Hirotaka, et al.. (2023). Giant seebeck effect in an undoped single crystal of 2,5,8-triphenylbenzo[1,2-b:3,4-b':5,6-b'']trifuran. Chemistry Letters. 53(2). 1 indexed citations
7.
Hiroshiba, Nobuya, Hirotaka Kojima, Satoshi Ohnishi, et al.. (2022). Broadband infrared absorption spectroscopy of low-frequency inter-molecular vibrations in crystalline poly(L-lactide). Physica B Condensed Matter. 649. 414488–414488. 4 indexed citations
8.
Benten, Hiroaki, Zhiyuan Liang, Naoki Oyaizu, et al.. (2022). Chain aggregation dictates bimolecular charge recombination and fill factor of all-polymer blend solar cells. Journal of Materials Chemistry A. 10(40). 21727–21737. 3 indexed citations
9.
Benten, Hiroaki, Noboru Ohta, Azusa Muraoka, et al.. (2020). Enhancement of Short-Range Ordering of Low-Bandgap Donor–Acceptor Conjugated Polymer in Polymer/Polymer Blend Films. Macromolecules. 53(15). 6630–6639. 9 indexed citations
10.
Suda, Masayuki, Vinich Promarak, Hirotaka Kojima, et al.. (2019). Light-driven molecular switch for reconfigurable spin filters. Nature Communications. 10(1). 2455–2455. 128 indexed citations
11.
Kojima, Hirotaka, Kohtaro Takahashi, Daiki Kuzuhara, et al.. (2018). Universality of the giant Seebeck effect in organic small molecules. Materials Chemistry Frontiers. 2(7). 1276–1283. 33 indexed citations
12.
Ito, Mitsuhiro, Takuya Koizumi, Hirotaka Kojima, Takeshi Saito, & Masakazu Nakamura. (2017). From materials to device design of a thermoelectric fabric for wearable energy harvesters. Journal of Materials Chemistry A. 5(24). 12068–12072. 126 indexed citations
13.
Kojima, Hirotaka, et al.. (2015). Giant Seebeck effect in pure fullerene thin films. Applied Physics Express. 8(12). 121301–121301. 24 indexed citations
14.
Higashino, Toshiki, Tomofumi Kadoya, Masaki Tanaka, et al.. (2014). High performance ambipolar organic field-effect transistors based on indigo derivatives. Journal of Materials Chemistry C. 2(43). 9311–9317. 76 indexed citations
15.
Kojima, Hirotaka, et al.. (2013). Correlation of mobility and molecular packing in organic transistors based on cycloalkyl naphthalene diimides. Journal of Materials Chemistry C. 1(34). 5395–5395. 48 indexed citations
16.
Higashino, Toshiki, et al.. (2012). Organic Semiconductors and Conductors with tert-Butyl Substituents. Crystals. 2(3). 1222–1238. 20 indexed citations
17.
Kojima, Hirotaka, Zhongyue Zhang, Kim R. Dunbar, & Takehiko Mori. (2012). Energy band structure and metal–organic interactions in tetracyanoquinodimethane (TCNQ) and N,N′-dicyanoquinonediimine (DCNQI) materials. Journal of Materials Chemistry C. 1(9). 1781–1781. 12 indexed citations
18.
Sawai, Jun, et al.. (2002). Indirect conductimetric assay of antibacterial activities. Journal of Industrial Microbiology & Biotechnology. 29(5). 296–298. 27 indexed citations
19.
Sawai, Jun, et al.. (2001). Heated Scallop-Shell Powder Slurry Treatment of Shredded Cabbage. Journal of Food Protection. 64(10). 1579–1583. 48 indexed citations
20.
Sawai, Jun, S Kasai, Hideo Igarashi, et al.. (2000). Far-infrared irradiation-induced injuries to Escherichia coli at below the lethal temperature. Journal of Industrial Microbiology & Biotechnology. 24(1). 19–24. 20 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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