Abstract: The edges of layered transition metal dichalcogenides (TMDs) are recognized as the active sites for electrocatalytic hydrogen evolution, therefore considerable efforts have been devoted to increasing the edge density of TMDs. Given that defect-enriched TMDs are synthesized at mild conditions, their low crystallinity normally results in poor electrochemical stability. Although high-temperature processing is efficient to achieve highly crystalline TMDs, which in turn leads to low electrocatalytic activity due to the loss of reactive defects and edge sites. In this work, defect-enriched WSe2 with high crystallinity was synthesized via a long-term ultrasonic treatment of crystalline WSe2 plates in ethanol. Few-layered WSe2 nanosheets (NSs) were firstly obtained by ultrasonication-assisted exfoliation of WSe2 plates, while island-like domains were subsequently formed under durable ultrasonication. The resultant defect-rich crystalline WSe2 NSs possessing large specific surface area, abundant active sites and high crystallinity exhibit superior electrocatalytic performance for hydrogen evolution reaction.
1 Zang Y, Niu S, Wu Y, et al. Nature Communications, 2019, 10(1), 1217. 2 Voiry D, Yang J, Chhowalla M. Advanced Materials, 2016, 28(29), 6197. 3 Shi Y, Zhang B. Chemical Society Reviews, 2016, 45(6), 1529. 4 Lu Q, Yu Y, Ma Q, et al. Advanced Materials, 2016, 28(10), 1917. 5 Jaramillo T F, Jørgensen K P, Bonde J, et al. Science, 2007, 317(5834), 100. 6 Kibsgaard J, Chen Z, Reinecke B N, et al. Nature Materials, 2012, 11, 963. 7 Tsai C, Chan K, Abild-Pedersen F, et al. Physical Chemistry Chemical Physics, 2014, 16(26), 13156. 8 Xie J, Zhang H, Li S, et al. Advanced Materials, 2013, 25(40), 5807. 9 Henckel D A, Lenz O M, Krishnan K M, et al. Nano Letters, 2018, 18(4), 2329. 10 Henckel D A, Lenz O, Cossairt B M. ACS Catalysis, 2017, 7(4), 2815. 11 Ji Q, Zhang Y, Shi J, et al. Advanced Materials, 2016, 28(29), 6207. 12 Eng A Y S, Ambrosi A, Sofer Z, et al. ACS Nano, 2014, 8(12), 12185. 13 Wang H, Lu Z, Kong D, et al. ACS Nano, 2014, 8(5), 4940. 14 Antunez P D, Webber D H, Brutchey R L. Chemistry of Materials, 2013, 25(12), 2385. 15 Wang X, Chen Y, Zheng B, et al. Journal of Alloys and Compounds, 2017, 691(698. 16 Li H, Zou J, Xie S, et al. Journal of Alloys and Compounds, 2017, 725(884. 17 Liang K, Yan Y, Guo L, et al. ACS Energy Letters, 2017, 2(6), 1315. 18 Velazquez J M, Saadi F H, Pieterick A P, et al. Journal of Electroanaly-tical Chemistry, 2014, 716, 45. 19 Wang H, Kong D, Johanes P, et al. Nano Letters, 2013, 13(7), 3426. 20 Li H, Zou J, Xie S, et al. Applied Surface Science, 2017, 425, 622. 21 Mazánek V, Mayorga-Martinez C C, Bouša D, et al. Nanoscale, 2018, 10(48), 23149. 22 Zhou H, Yu F, Sun J, et al. Nano Letters, 2016, 16(12), 7604. 23 Wang X, Chen Y, Zheng B, et al. Electrochimica Acta, 2016, 222,1293. 24 Meiron O E, Kuraganti V, Hod I, et al. Nanoscale, 2017, 9(37), 13998. 25 Gong Q, Cheng L, Liu C, et al. ACS Catalysis, 2015, 5(4), 2213. 26 Zou M, Chen J, Xiao L, et al. Journal of Materials Chemistry A, 2015, 3(35), 18090. 27 Seo S, Kim S, Choi H, et al. Advanced Science, 2019, 6(13), 1900301. 28 Vikraman D, Hussain S, Truong L, et al. Applied Surface Science, 2019, 480,611. 29 Zhang G, Zheng X, Xu Q, et al. Journal of Materials Chemistry A, 2018, 6(11), 4793. 30 Xu S, Li D, Wu P. Advanced Functional Materials, 2015, 25(7), 1127. 31 Wang X, Chen Y, Qi F, et al. Chemical Communications, 2016, 72,74. 32 Cho J S, Park S K, Jeon K M, et al. Applied Surface Science, 2018, 459,309. 33 Liu Z, Zhao H, Li N, et al. Inorganic Chemistry Frontiers, 2016, 3(2), 313. 34 Li J, Liu P, Qu Y, et al. International Journal of Hydrogen Energy, 2018, 43(5), 2601. 35 Huang Y, Ma Z, Hu Y, et al. RSC Advances, 2016, 6(57), 51725. 36 Qian J, Li Z, Guo X, et al. Industrial & Engineering Chemistry Research, 2018, 57(2), 483. 37 Sun Y, Zhang X, Mao B, et al. Chemical Communications, 2016, 52(99), 14266. 38 Yu X, Prévot M S, Guijarro N, et al. Nature Communications, 2015, 6(1), 7596. 39 Wu Z, Fang B, Wang Z, et al. ACS Catalysis, 2013, 3(9), 2101. 40 Xu K, Wang F, Wang Z, et al. ACS Nano, 2014, 8(8), 8468. 41 Yin X L, Liu J, Jiang W J, et al. Chemical Communications, 2015, 51(72), 13842. 42 Zou M, Zhang J, Zhu H, et al. Journal of Materials Chemistry A, 2015, 3(23), 12149. 43 Liu J, Zeng M, Wang L, et al. Small, 2016, 12(41), 5741.