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Photodetectors play an essential role in optical communications, environmental monitoring, and medical imaging, and their performance strongly depends on the properties of the optoelectronic materials. Therefore, the exploration of high-performance optoelectronic materials has long been a research focus in the field of materials science. Viologen-based organic materials, owing to their unique redox and chromic characteristics, have been extensively utilized in electrochromic devices, biosensors, and flow batteries. In this work, a viologen complex containing the transition metal element Co, {[Co(BPYBDC) (H2O)5]·(BDC)·H2O} (denoted as 1-Co) was designed and successfully synthesized. A series of in-situ high-pressure characterization techniques were employed to systematically investigate its structural and optoelectronic behaviors. The results reveal that 1-Co crystallizes in the Pc space group and remains structurally stable up to 11.6 GPa without any phase transition. UV-visible absorption spectroscopy shows a red-shift of the absorption edge upon compression, accompanied by a color change from colorless and transparent to yellow, indicating a pressure-induced narrowing of the optical bandgap. Consistent with the bandgap narrowing, impedance measurements demonstrate a significant reduction in the total resistance under compression, which remains about two orders of magnitude lower than the initial value after decompression. Furthermore, the photocurrent response is markedly suppressed under compression and barely recovers upon pressure release. This behavior can be attributed to the enhanced recombination of electrons with viologen groups under compression, leading to the formation of stable viologen radical states. These localized radicals cannot effectively participate in the separation and transport of photogenerated carriers, thereby contributing little to the photocurrent. These findings suggest that high pressure effectively modulates the optical and electrical behaviors of 1-Co by tuning intermolecular interactions and the electronic band structure, providing valuable insights into the pressure-dependent behavior of viologen-based materials.
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Keywords:
- Viologen metal-organic materials /
- high-pressure regulation /
- crystal structure /
- optoelectronic properties
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[1] Michaelis L, Hill E S 1933 J. Gen. Physiol. 16 859
[2] Puguan J M C, Rathod P V, Kim H 2021 ACS Appl. Mater. Interfaces 13 36330
[3] Sun C, Wang M, Li P, Guo G 2017 Angew. Chem. 129 569
[4] Sun M, Lv J, Xu H, Zhang L, Zhong Y, Chen Z, Sui X, Wang B, Feng X, Mao Z 2020 Cellulose 27 2939
[5] Lin X Y, Zhao L M, Wang D H, Wang Y K, Li M, Li H H, Chen Z R 2018 Inorg. Chem. Front. 5 189
[6] Xu X, Liu T, Yang M, Tian A, Ying J 2023 Mater. Lett. 337 133974
[7] Li S L, Li M, Zhang Y, Xu H M, Zhang X M 2020 Inorg. Chem. 59 9047
[8] Tan Y, Fu Z, Zeng Y, Chen H, Liao S, Zhang J, Dai J 2012 J. Mater. Chem. 22 17452
[9] Li L, Wang J R, Hua Y, Guo Y, Fu C, Sun Y N, Zhang H 2019 J. Mater. Chem. C 7 38
[10] Sui Q, Wang H, Zhang Y, Sun R, Jin X, Wang B, Wang L, Gao S 2023 Chem. – Eur. J. 29 e202301575
[11] Li A, Xu S, Bi C, Geng Y, Cui H, Xu W 2021 Mater. Chem. Front. 5 2588
[12] Sui Q, Ren X T, Dai Y X, Wang K, Li W T, Gong T, Fang J J, Zou B, Gao E Q, Wang L 2017 Chem. Sci. 8 2758
[13] Monk P M S 1998 The viologens: Physicochemical properties, synthesis and applications of the salts of 4,4’-bipyridine (New York Weinheim: Wiley) pp311
[14] Drickamer H G, Bray K L 1990 Acc. Chem. Res. 23 55
[15] Pinkowicz D, Rams M, Mišek M, Kamenev K V, Tomkowiak H, Katrusiak A, Sieklucka B 2015 J. Am. Chem. Soc. 137 8795
[16] Song K, Miller R D, Wallraff G M, Rabolt J F 1991 Macromolecules 24 4084
[17] Chung W, Shibaguchi H, Terao K, Fujiki M, Naito M 2011 Macromolecules 44 6568
[18] Song K, Kuzmany H, Wallraff G M, Miller R D, Rabolt J F 1990 Macromolecules 23 3870
[19] Sato T, Yagi T, Tajima H, Fukuda T, Yamamoto T 2008 React. Funct. Polym. 68 369
[20] Meng X, Qi G, Zhang C, Wang K, Zou B, Ma Y 2015 Chem. Commun. 51 9320
[21] Rahman S, Samanta S, Kuzmin A, Errandonea D, Saqib H, Brewe D L, Kim J, Lu J, Wang L 2019 Adv. Sci. 6 1901132
[22] Liu K, Tang J, Dai L, Yang Y, Liang W, Luo S, Luo G, Zhang J, Li Q, Wang T, Wang R, Dong J, Meng Y, Liu G 2025 Appl. Phys. Lett. 127 022102
[23] Yamanoi Y, Terasaki N, Miyachi M, Inoue Y, Nishihara H 2012 Thin Solid Films 520 5123
[24] Shen Z W, Wu Z Y, Wang S J, Wang H C, Li H K, Song J, Gao G Y, Wang L, Tian Y J 2024 Chin. Phys. Lett. 41 117101 (in Chinese)[申志伟，邬中炎，王邵杰，王贺冲，李宏凯，宋静，高国英，王霖，田永君2024 中国物理快报 41 117101]
[25] Prescher C, Prakapenka V B 2015 High Press. Res. 35 223
[26] Toby B H, Von Dreele R B 2013 J. Appl. Crystallogr. 46 544
[27] Rietveld H M 1969 J. Appl. Crystallogr. 2 65
[28] Fang S, Li Q, Li Z, Dong Q, Jing X, Li C, Li H, Liu B, Liu R, Liu B 2023 Mater. Res. Lett. 11 134
[29] Wang N, Zhang G, Wang G, Feng Z, Li Q, Zhang H, Li Y, Liu C 2024 Small 20 2400216
[30] Konstantatos G, Sargent E H 2010 Nat. Nanotechnol. 5 391
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