臺灣博碩士論文加值系統

水分解產氫(Hydrogen evolution reaction by water splitting)是個乾淨、環保，對環境友善的製程，堪稱是現今最具有潛力的再生能源之一。傳統產氫效率低，需要藉由電觸媒的協助，二硫化鉬(Molybdenum disulfide, MoS2)擁有催化活性大及適中氫吸附自由能等優勢，然而其最大瓶頸為導電性較低、反應點侷限及製程時間長。為了改善這些缺點，通常會透過與導電性良好的材料結合，提升電子傳遞速率並可扮演MoS2生長基材的角色。本研究成功利用簡易、低成本之熱注入法製備油胺包覆之單層二硫化鉬(OLA-protected monolayer MoS2)，並透過製程參數改變，即可形成不同種與導電材結合的複合物(MoS2-MoO2, MoS2-carbon)。其中透過反應溫度及時間的增加，產生MoO3→MoO2→MoS2的趨勢，顯微結構證實形成二硫化鉬-二氧化鉬核殼結構(MoS2-MoO2 core-shell structure)；除此之外，利用油胺(Oleylamine, OLA)作為製備溶劑，它更會滲入MoS2層間將之分離成單層MoS2，並透過進一步退火將缺乏導電及催化性之OLA高溫碳化成carbon。MoS2層間膨脹，其層間距從0.61 nm膨脹至1.02 nm，且單層MoS2和carbon彼此交層排列，形成二硫化鉬-碳材交層結構(MoS2-carbon interoverlapped structure)。MoS2-導電材複合材料之電催化效能，皆較純相MoS2、MoO2大幅提升，起始電位及塔弗斜率有效降低。MoS2-MoO2顯著的效果提升主要是來自MoS2豐富的活性點及MoO2有助於載子傳遞方向的改善；而MoS2-carbon則是因為OLA將MoS2層間距增加，形成單層結構，單層MoS2及硫缺陷貢獻豐富活性催化點，且交替碳層造成MoS2層間導電性提升。

Hydrogen has been considered as one of the most promising renewable energy for production and storage. MoS2-MoO2 composite can act as an excellent electrocatalyst for hydrogen evolution reaction (HER) because of the presence of high concentration of effective active sites and good conductivity. Here, we report an efficient method to synthesize MoS2-MoO2 composite by hot-injection method using MoO3 and S powder as precursors with oleic acid (OA) and oleylamine (OLA) as solvent, respectively. With increasing reaction temperature and time, OA will reorganize the octahedral units of MoO3 and gradually turn into low valence of Mo. After injecting S-precursor, OLA will first reduce Mo-precursor to MoO2 as core, and then S atoms replace O atoms to form MoS2 as shell, eventually forming MoS2-MoO2 core-shell structure. A Tafel slope of 129 mV/dec was measured for MoS2-MoO2 composite, which is much better than MoS2 and MoO2 alone. The enhanced HER performance is attributed to the improved charge transfer direction by MoO2 and the abundance active sites from MoS2.

中文摘要 I
Extended Abstract II
致謝 XV
目錄 XVII
表目錄 XX
圖目錄 XXI
第一章、緒論 1
1.1 前言 1
1.2 二硫化鉬的發展 3
1.3 二硫化鉬用於水分解產氫的發展史 4
1.4 研究動機與目的 6
第二章、文獻回顧 7
2.1 水分解產氫反應 (Water Splitting for Hydrogen Evolution Reaction) 7
2.2 電催化材料選用 12
2.2.1 電催化材料選用要求 12
2.2.2 評斷性質表現的重要參數 14
2.2.3 常用的電催化材料 19
2.3 二硫化鉬 (Molybdenum disulfide, MoS2) 27
2.3.1 結構與其多形體 (Polymorph) 27
2.3.2 催化性質 29
2.3.3 製程 32
2.4 二硫化鉬應用於電催化產氫 36
2.4.1 少層數(Few-layer)、層間膨脹(Layer-expanded)之MoS2 36
2.4.2 MoS2與導電材結合 39
第三章、實驗方法與分析設備 49
3.1 實驗藥品 49
3.2 實驗裝置 50
3.2.1 熱注入裝置 50
3.2.2 管狀高溫爐裝置 51
3.2.3 電化學量測裝置 52
3.3 實驗流程 53
3.3.1 油胺包覆之單層二硫化鉬 (OLA-protected Monolayer MoS2) 53
3.3.2 二硫化鉬-二氧化鉬複合材料 (MoS2-MoO2) 55
3.3.3 二硫化鉬-碳材複合材料 (MoS2-carbon) 57
3.3.4 製備工作電極 (Working electrode preparation) 59
3.4 分析儀器 60
3.4.1 微結構與成分分析 60
3.4.2 電化學性質分析 61
第四章、結果與討論 62
Part 1 純相二硫化鉬 62
4.1 油胺包覆之單層二硫化鉬 (OLA-protected Monolayer MoS2) 62
4.1.1 成分與鍵結分析 62
4.1.2 微結構分析 65
4.1.3 價數態與元素能譜分析 67
4.1.4 電催化產氫效能量測與機制探討 69
4.1.5 小結 71
Part 2 二硫化鉬與導電材之複合相 72
4.2 二硫化鉬-二氧化鉬核殼結構 (MoS2-MoO2 core-shell structure) 72
4.2.1 成分與鍵結分析 73
§ 注入前Mo-precursor隨反應溫度與時間的變化 73
§ 注入S源後隨反應溫度與時間的變化 76
4.2.2 微結構分析 81
4.2.3 價數態與元素能譜分析 86
4.2.4 電催化產氫效能量測與機制探討 88
4.2.5 小結 91
4.3 二硫化鉬-碳交互層狀結構 (MoS2-carbon interoverlapped structure) 92
4.3.1 成分與鍵結分析 92
4.3.2 微結構分析 95
4.3.3 價數態與元素能譜分析 97
4.3.4 電催化產氫效能量測與機制探討 99
4.3.5 小結 102
第五章、結論 103
第六章、參考文獻 105
附錄：發表論文於國內外期刊 117

[1]Q. P. Lu, Y. F. Yu, Q. L. Ma, B. Chen, and H. Zhang, 2D Transition-Metal-Dichalcogenide-Nanosheet-Based Composites for Photocatalytic and Electrocatalytic Hydrogen Evolution Reactions, Advanced Materials, vol. 28, pp. 1917-1933, Mar 2016.
[2]B. Sakintuna, F. Lamari-Darkrim, and M. Hirscher, Metal hydride materials for solid hydrogen storage: A review, International Journal of Hydrogen Energy, vol. 32, pp. 1121-1140, Jun 2007.
[3]A. Iulianelli, S. Liguori, J. Wilcox, and A. Basile, Advances on methane steam reforming to produce hydrogen through membrane reactors technology: A review, Catalysis Reviews, vol. 58, pp. 1-35, 2016.
[4]F. M. Wang, T. A. Shifa, X. Y. Zhan, Y. Huang, K. L. Liu, Z. Z. Cheng, et al., Recent advances in transition-metal dichalcogenide based nanomaterials for water splitting, Nanoscale, vol. 7, pp. 19764-19788, 2015.
[5]M. R. Gao, Y. F. Xu, J. Jiang, and S. H. Yu, Nanostructured metal chalcogenides: synthesis, modification, and applications in energy conversion and storage devices, Chemical Society Reviews, vol. 42, pp. 2986-3017, 2013.
[6]M. A. Abbas and J. H. Bang, Rising Again: Opportunities and Challenges for Platinum-Free Electrocatalysts, Chemistry of Materials, vol. 27, pp. 7218-7235, Nov 2015.
[7]E. Gibney, The super materials that could trump graphene, Nature, vol. 522, pp. 274-276, 2015.
[8]M. Chhowalla, H. S. Shin, G. Eda, L. J. Li, K. P. Loh, and H. Zhang, The chemistry of two-dimensional layered transition metal dichalcogenide nanosheets, Nature Chemistry, vol. 5, pp. 263-275, Apr 2013.
[9]A. K. Geim and K. S. Novoselov, The rise of graphene, Nature materials, vol. 6, pp. 183-191, 2007.
[10]T. Stephenson, Z. Li, B. Olsen, and D. Mitlin, Lithium ion battery applications of molybdenum disulfide (MoS2) nanocomposites, Energy ＆ Environmental Science, vol. 7, pp. 209-231, Jan 2014.
[11]M. Pumera, Z. Sofer, and A. Ambrosi, Layered transition metal dichalcogenides for electrochemical energy generation and storage, Journal of Materials Chemistry A, vol. 2, pp. 8981-8987, 2014.
[12]C. L. Tan and H. Zhang, Two-dimensional transition metal dichalcogenide nanosheet-based composites, Chemical Society Reviews, vol. 44, pp. 2713-2731, 2015.
[13]H. T. Wang, H. T. Yuan, S. S. Hong, Y. B. Li, and Y. Cui, Physical and chemical tuning of two-dimensional transition metal dichalcogenides, Chemical Society Reviews, vol. 44, pp. 2664-2680, 2015.
[14]H. Schmidt, F. Giustiniano, and G. Eda, Electronic transport properties of transition metal dichalcogenide field-effect devices: surface and interface effects, Chemical Society Reviews, vol. 44, pp. 7715-7736, 2015.
[15]Q. H. Wang, K. Kalantar-Zadeh, A. Kis, J. N. Coleman, and M. S. Strano, Electronics and optoelectronics of two-dimensional transition metal dichalcogenides, Nature nanotechnology, vol. 7, pp. 699-712, 2012.
[16]C. G. Morales-Guio, L. A. Stern, and X. L. Hu, Nanostructured hydrotreating catalysts for electrochemical hydrogen evolution, Chemical Society Reviews, vol. 43, pp. 6555-6569, Sep 2014.
[17]H. Tributsch and J. Bennett, Electrochemistry and photochemistry of MoS2 layer crystals. I, Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, vol. 81, pp. 97-111, 1977.
[18]T. F. Jaramillo, K. P. Jørgensen, J. Bonde, J. H. Nielsen, S. Horch, and I. Chorkendorff, Identification of active edge sites for electrochemical H2 evolution from MoS2 nanocatalysts, science, vol. 317, pp. 100-102, 2007.
[19]B. Hinnemann, P. G. Moses, J. Bonde, K. P. Jørgensen, J. H. Nielsen, S. Horch, et al., Biomimetic hydrogen evolution: MoS2 nanoparticles as catalyst for hydrogen evolution, Journal of the American Chemical Society, vol. 127, pp. 5308-5309, 2005.
[20]J. A. Turner, A realizable renewable energy future, Science, vol. 285, pp. 687-689, 1999.
[21]A. B. Laursen, S. Kegnaes, S. Dahl, and I. Chorkendorff, Molybdenum sulfides-efficient and viable materials for electro - and photoelectrocatalytic hydrogen evolution, Energy ＆ Environmental Science, vol. 5, pp. 5577-5591, Feb 2012.
[22]R. De Levie, The electrolysis of water, Journal of Electroanalytical Chemistry, vol. 476, pp. 92-93, 1999.
[23]A. Paets van Troostwijk and J. Deiman, Sur une manière de décomposer l’eau en air inflammable et en air vital, J. Phys, vol. 35, pp. 369-378, 1789.
[24]Y. C. Lin, D. O. Dumcencon, Y. S. Huang, and K. Suenaga, Atomic mechanism of the semiconducting-to-metallic phase transition in single-layered MoS2, Nature Nanotechnology, vol. 9, pp. 391-396, May 2014.
[25]C. Tsai, K. R. Chan, J. K. Norskov, and F. Abild-Pedersen, Theoretical insights into the hydrogen evolution activity of layered transition metal dichalcogenides, Surface Science, vol. 640, pp. 133-140, Oct 2015.
[26]M. A. Lukowski, A. S. Daniel, F. Meng, A. Forticaux, L. S. Li, and S. Jin, Enhanced Hydrogen Evolution Catalysis from Chemically Exfoliated Metallic MoS2 Nanosheets, Journal of the American Chemical Society, vol. 135, pp. 10274-10277, Jul 2013.
[27]Y. J. Tang, M. R. Gao, C. H. Liu, S. L. Li, H. L. Jiang, Y. Q. Lan, et al., Porous Molybdenum‐Based Hybrid Catalysts for Highly Efficient Hydrogen Evolution, Angewandte Chemie International Edition, vol. 54, pp. 12928-12932, 2015.
[28]J. Xie, H. Zhang, S. Li, R. Wang, X. Sun, M. Zhou, et al., Defect‐rich MoS2 ultrathin nanosheets with additional active edge sites for enhanced electrocatalytic hydrogen evolution, Advanced Materials, vol. 25, pp. 5807-5813, 2013.
[29]D. Kong, H. Wang, J. J. Cha, M. Pasta, K. J. Koski, J. Yao, et al., Synthesis of MoS2 and MoSe2 films with vertically aligned layers, Nano letters, vol. 13, pp. 1341-1347, 2013.
[30]D. Y. Wang, M. Gong, H. L. Chou, C. J. Pan, H. A. Chen, Y. P. Wu, et al., Highly Active and Stable Hybrid Catalyst of Cobalt-Doped FeS2 Nanosheets-Carbon Nanotubes for Hydrogen Evolution Reaction, Journal of the American Chemical Society, vol. 137, pp. 1587-1592, Feb 2015.
[31]D. J. Li, U. N. Maiti, J. Lim, D. S. Choi, W. J. Lee, Y. Oh, et al., Molybdenum Sulfide/N-Doped CNT Forest Hybrid Catalysts for High-Performance Hydrogen Evolution Reaction, Nano Letters, vol. 14, pp. 1228-1233, Mar 2014.
[32]H. Li, K. Yu, C. Li, Z. Tang, B. Guo, X. Lei, et al., Charge-Transfer Induced High Efficient Hydrogen Evolution of MoS2/graphene Cocatalyst, Scientific reports, vol. 5, 2015.
[33]J. D. Benck, T. R. Hellstern, J. Kibsgaard, P. Chakthranont, and T. F. Jaramillo, Catalyzing the hydrogen evolution reaction (HER) with molybdenum sulfide nanomaterials, ACS Catalysis, vol. 4, pp. 3957-3971, 2014.
[34]X. Zou and Y. Zhang, Noble metal-free hydrogen evolution catalysts for water splitting, Chemical Society Reviews, vol. 44, pp. 5148-5180, 2015.
[35]J. Chen, B. Lim, E. P. Lee, and Y. Xia, Shape-controlled synthesis of platinum nanocrystals for catalytic and electrocatalytic applications, Nano Today, vol. 4, pp. 81-95, 2009.
[36]J. Greeley, T. F. Jaramillo, J. Bonde, I. Chorkendorff, and J. K. Nørskov, Computational high-throughput screening of electrocatalytic materials for hydrogen evolution, Nature materials, vol. 5, pp. 909-913, 2006.
[37]X. Huang, Z. Y. Zeng, S. Y. Bao, M. F. Wang, X. Y. Qi, Z. X. Fan, et al., Solution-phase epitaxial growth of noble metal nanostructures on dispersible single-layer molybdenum disulfide nanosheets, Nature Communications, vol. 4, Feb 2013.
[38]Y. J. Wang, B. Z. Fang, H. Li, X. T. T. Bi, and H. J. Wang, Progress in modified carbon support materials for Pt and Pt-alloy cathode catalysts in polymer electrolyte membrane fuel cells, Progress in Materials Science, vol. 82, pp. 445-498, Sep 2016.
[39]E. J. Popczun, J. R. McKone, C. G. Read, A. J. Biacchi, A. M. Wiltrout, N. S. Lewis, et al., Nanostructured nickel phosphide as an electrocatalyst for the hydrogen evolution reaction, Journal of the American Chemical Society, vol. 135, pp. 9267-9270, 2013.
[40]Y. Zhao, F. Zhao, X. Wang, C. Xu, Z. Zhang, G. Shi, et al., Graphitic Carbon Nitride Nanoribbons: Graphene‐Assisted Formation and Synergic Function for Highly Efficient Hydrogen Evolution, Angewandte Chemie International Edition, vol. 53, pp. 13934-13939, 2014.
[41]Y. Zheng, Y. Jiao, L. H. Li, T. Xing, Y. Chen, M. Jaroniec, et al., Toward design of synergistically active carbon-based catalysts for electrocatalytic hydrogen evolution, ACS nano, vol. 8, pp. 5290-5296, 2014.
[42]J. Yang and H. S. Shin, Recent advances in layered transition metal dichalcogenides for hydrogen evolution reaction, Journal of Materials Chemistry A, vol. 2, pp. 5979-5985, 2014.
[43]B. Radisavljevic, A. Radenovic, J. Brivio, V. Giacometti, and A. Kis, Single-layer MoS2 transistors, Nat Nanotechnol, vol. 6, pp. 147-50, Mar 2011.
[44]Q. H. Wang, K. Kalantar-Zadeh, A. Kis, J. N. Coleman, and M. S. Strano, Electronics and optoelectronics of two-dimensional transition metal dichalcogenides, Nat Nanotechnol, vol. 7, pp. 699-712, 2012.
[45]J. Bonde, P. G. Moses, T. F. Jaramillo, J. K. Nørskov, and I. Chorkendorff, Hydrogen evolution on nano-particulate transition metal sulfides, Faraday discussions, vol. 140, pp. 219-231, 2009.
[46]A. B. Laursen, S. Kegnæs, S. Dahl, and I. Chorkendorff, Molybdenum sulfides—efficient and viable materials for electro-and photoelectrocatalytic hydrogen evolution, Energy ＆ Environmental Science, vol. 5, pp. 5577-5591, 2012.
[47]M. A. Lukowski, A. S. Daniel, F. Meng, A. Forticaux, L. Li, and S. Jin, Enhanced hydrogen evolution catalysis from chemically exfoliated metallic MoS2 nanosheets, Journal of the American Chemical Society, vol. 135, pp. 10274-10277, 2013.
[48]M. Yi and Z. Shen, A review on mechanical exfoliation for the scalable production of graphene, Journal of Materials Chemistry A, vol. 3, pp. 11700-11715, 2015.
[49]A. J. Smith, Y. H. Chang, K. Raidongia, T. Y. Chen, L. J. Li, and J. Huang, Molybdenum sulfide supported on crumpled graphene balls for electrocatalytic hydrogen production, Advanced Energy Materials, vol. 4, 2014.
[50]H. Schmidt, S. Wang, L. Chu, M. Toh, R. Kumar, W. Zhao, et al., Transport properties of monolayer MoS2 grown by chemical vapor deposition, Nano letters, vol. 14, pp. 1909-1913, 2014.
[51]M. Acerce, D. Voiry, and M. Chhowalla, Metallic 1T phase MoS2 nanosheets as supercapacitor electrode materials, Nature nanotechnology, vol. 10, pp. 313-318, 2015.
[52]Z. Zeng, Z. Yin, X. Huang, H. Li, Q. He, G. Lu, et al., Single‐layer semiconducting nanosheets: high‐yield preparation and device fabrication, Angewandte Chemie International Edition, vol. 50, pp. 11093-11097, 2011.
[53]Y. H. Lee, X. Q. Zhang, W. J. Zhang, M. T. Chang, C. T. Lin, K. D. Chang, et al., Synthesis of Large-Area MoS2 Atomic Layers with Chemical Vapor Deposition, Advanced Materials, vol. 24, pp. 2320-2325, May 2012.
[54]K. Kobayashi and J. Yamauchi, Electronic structure and scanning-tunneling-microscopy image of molybdenum dichalcogenide surfaces, Physical Review B, vol. 51, p. 17085, 1995.
[55]C. Tsai, F. Abild-Pedersen, and J. K. Nørskov, Tuning the MoS2 edge-site activity for hydrogen evolution via support interactions, Nano letters, vol. 14, pp. 1381-1387, 2014.
[56]J. Xie, J. Zhang, S. Li, F. Grote, X. Zhang, H. Zhang, et al., Controllable disorder engineering in oxygen-incorporated MoS2 ultrathin nanosheets for efficient hydrogen evolution, Journal of the American Chemical Society, vol. 135, pp. 17881-17888, 2013.
[57]M.-R. Gao, M. K. Chan, and Y. Sun, Edge-terminated molybdenum disulfide with a 9.4-A interlayer spacing for electrochemical hydrogen production, Nature communications, vol. 6, 2015.
[58]Z.-T. Shi, W. Kang, J. Xu, Y.-W. Sun, M. Jiang, T.-W. Ng, et al., Hierarchical nanotubes assembled from MoS 2-carbon monolayer sandwiched superstructure nanosheets for high-performance sodium ion batteries, Nano Energy, vol. 22, pp. 27-37, 2016.
[59]H. Jiang, D. Ren, H. Wang, Y. Hu, S. Guo, H. Yuan, et al., 2D monolayer MoS2–carbon interoverlapped superstructure: Engineering ideal atomic interface for lithium ion storage, Advanced Materials, vol. 27, pp. 3687-3695, 2015.
[60]N. Savjani, E. A. Lewis, M. A. Bissett, J. R. Brent, R. A. Dryfe, S. J. Haigh, et al., Synthesis of Lateral Size-Controlled Monolayer 1 H-MoS2@ Oleylamine as Supercapacitor Electrodes, Chemistry of Materials, vol. 28, pp. 657-664, 2016.
[61]C. Altavilla, M. Sarno, and P. Ciambelli, A Novel Wet Chemistry Approach for the Synthesis of Hybrid 2D Free-Floating Single or Multilayer Nanosheets of MS2@ oleylamine (M Mo, W), Chemistry of Materials, vol. 23, pp. 3879-3885, 2011.
[62]J. Zhou, J. Qin, X. Zhang, C. Shi, E. Liu, J. Li, et al., 2D space-confined synthesis of few-layer MoS2 anchored on carbon nanosheet for lithium-ion battery anode, ACS nano, vol. 9, pp. 3837-3848, 2015.
[63]X. Xie, Z. Ao, D. Su, J. Zhang, and G. Wang, MoS2/Graphene Composite Anodes with Enhanced Performance for Sodium‐Ion Batteries: The Role of the Two‐Dimensional Heterointerface, Advanced Functional Materials, vol. 25, pp. 1393-1403, 2015.
[64]Y. Shi, Y. Wang, J. I. Wong, A. Y. S. Tan, C.-L. Hsu, L.-J. Li, et al., Self-assembly of hierarchical MoSx/CNT nanocomposites (2( x( 3): towards high performance anode materials for lithium ion batteries, Scientific reports, vol. 3, 2013.
[65]K. Chang, W. Chen, L. Ma, H. Li, H. Li, F. Huang, et al., Graphene-like MoS 2/amorphous carbon composites with high capacity and excellent stability as anode materials for lithium ion batteries, Journal of Materials Chemistry, vol. 21, pp. 6251-6257, 2011.
[66]B. Hu, L. Q. Mai, W. Chen, and F. Yang, From MoO3 Nanobelts to MoO2 Nanorods: Structure Transformation and Electrical Transport, Acs Nano, vol. 3, pp. 478-482, Feb 2009.
[67]B. Hu, L. Mai, W. Chen, and F. Yang, From MoO3 nanobelts to MoO2 nanorods: structure transformation and electrical transport, Acs Nano, vol. 3, pp. 478-482, 2009.
[68]J. Zhan, Z. Zhang, X. Qian, C. Wang, Y. Xie, and Y. Qian, Solvothermal synthesis of nanocrystalline MoS 2 from MoO 3 and elemental sulfur, Journal of Solid State Chemistry, vol. 141, pp. 270-273, 1998.
[69]P. Kumar, M. Singh, R. K. Sharma, and G. B. Reddy, Reaction mechanism of core-shell MoO2/MoS2 nanoflakes via plasma-assisted sulfurization of MoO3, Materials Research Express, vol. 3, May 2016.
[70]W. J. Zhou, D. M. Hou, Y. H. Sang, S. H. Yao, J. Zhou, G. Q. Li, et al., MoO2 nanobelts@nitrogen self-doped MoS2 nanosheets as effective electrocatalysts for hydrogen evolution reaction, Journal of Materials Chemistry A, vol. 2, pp. 11358-11364, 2014.
[71]L. J. Yang, W. J. Zhou, D. M. Hou, K. Zhou, G. Q. Li, Z. H. Tang, et al., Porous metallic MoO2-supported MoS2 nanosheets for enhanced electrocatalytic activity in the hydrogen evolution reaction, Nanoscale, vol. 7, pp. 5203-5208, 2015.
[72]Y. R. Liu, J. X. Gou, X. Li, B. Dong, G. Q. Han, W. H. Hu, et al., Self-sacrificial template method of Mo3O10( C6H8N)(2)center dot 2H(2)O to fabricate MoS2/carbon-doped MoO2 nanobelts as efficient electrocatalysts for hydrogen evolution reaction, Electrochimica Acta, vol. 216, pp. 397-404, Oct 2016.
[73]R. D. Nikam, A. Y. Lu, P. A. Sonawane, U. R. Kumar, K. Yadav, L. J. Li, et al., Three-Dimensional Heterostructures of MoS2 Nanosheets on Conducting MoO2 as an Efficient Electrocatalyst To Enhance Hydrogen Evolution Reaction, Acs Applied Materials ＆ Interfaces, vol. 7, pp. 23328-23335, Oct 2015.
[74]B. W. Jin, X. M. Zhou, L. Huang, M. Licklederer, M. Yang, and P. Schmuki, Aligned MoOx/MoS2 Core-Shell Nanotubular Structures with a High Density of Reactive Sites Based on Self-Ordered Anodic Molybdenum Oxide Nanotubes, Angewandte Chemie-International Edition, vol. 55, pp. 12252-12256, Sep 2016.
[75]Y. G. Li, H. L. Wang, L. M. Xie, Y. Y. Liang, G. S. Hong, and H. J. Dai, MoS2 Nanoparticles Grown on Graphene: An Advanced Catalyst for the Hydrogen Evolution Reaction, Journal of the American Chemical Society, vol. 133, pp. 7296-7299, May 2011.
[76]Y. Yan, X. Ge, Z. Liu, J.-Y. Wang, J.-M. Lee, and X. Wang, Facile synthesis of low crystalline MoS 2 nanosheet-coated CNTs for enhanced hydrogen evolution reaction, Nanoscale, vol. 5, pp. 7768-7771, 2013.
[77]Y. Guo, X. Zhang, X. Zhang, and T. You, Defect-and S-rich ultrathin MoS 2 nanosheet embedded N-doped carbon nanofibers for efficient hydrogen evolution, Journal of Materials Chemistry A, vol. 3, pp. 15927-15934, 2015.
[78]L. Yang, W. Zhou, J. Lu, D. Hou, Y. Ke, G. Li, et al., Hierarchical spheres constructed by defect-rich MoS 2/carbon nanosheets for efficient electrocatalytic hydrogen evolution, Nano Energy, vol. 22, pp. 490-498, 2016.
[79]X. Zheng, J. Xu, K. Yan, H. Wang, Z. Wang, and S. Yang, Space-confined growth of MoS2 nanosheets within graphite: The layered hybrid of MoS2 and graphene as an active catalyst for hydrogen evolution reaction, Chemistry of Materials, vol. 26, pp. 2344-2353, 2014.
[80]W.-H. Hu, R. Yu, G.-Q. Han, Y.-R. Liu, B. Dong, Y.-M. Chai, et al., Facile synthesis of MoS 2/RGO in dimethyl-formamide solvent as highly efficient catalyst for hydrogen evolution, Materials Letters, vol. 161, pp. 120-123, 2015.
[81]Y. H. Chang, C. T. Lin, T. Y. Chen, C. L. Hsu, Y. H. Lee, W. Zhang, et al., Highly Efficient Electrocatalytic Hydrogen Production by MoSx Grown on Graphene‐Protected 3D Ni Foams, Advanced Materials, vol. 25, pp. 756-760, 2013.
[82]T.-Y. Chen, Y.-H. Chang, C.-L. Hsu, K.-H. Wei, C.-Y. Chiang, and L.-J. Li, Comparative study on MoS 2 and WS 2 for electrocatalytic water splitting, international journal of hydrogen energy, vol. 38, pp. 12302-12309, 2013.
[83]Y.-H. Chang, R. D. Nikam, C.-T. Lin, J.-K. Huang, C.-C. Tseng, C.-L. Hsu, et al., Enhanced Electrocatalytic Activity of MoS x on TCNQ-Treated Electrode for Hydrogen Evolution Reaction, ACS applied materials ＆ interfaces, vol. 6, pp. 17679-17685, 2014.
[84]C.-L. Hsu, Y.-H. Chang, T.-Y. Chen, C.-C. Tseng, K.-H. Wei, and L.-J. Li, Enhancing the electrocatalytic water splitting efficiency for amorphous MoS x, international journal of hydrogen energy, vol. 39, pp. 4788-4793, 2014.
[85]Y. Zhou, H. Xiao, S. Wang, X. Pan, Z. Wang, C. An, et al., Synthesis of layer-expanded MoS 2 nanosheets/carbon fibers nanocomposites for electrochemical hydrogen evolution reaction, Materials Chemistry and Physics, vol. 183, pp. 18-23, 2016.
[86]V. Koroteev, L. Bulusheva, I. Asanov, E. Shlyakhova, D. Vyalikh, and A. Okotrub, Charge transfer in the MoS2/carbon nanotube composite, The Journal of Physical Chemistry C, vol. 115, pp. 21199-21204, 2011.
[87]R. Ding, Y. Wu, Y. Chen, H. Chen, J. Wang, Y. Shi, et al., Catalytic hydrodeoxygenation of palmitic acid over a bifunctional Co-doped MoO 2/CNTs catalyst: an insight into the promoting effect of cobalt, Catalysis Science ＆ Technology, vol. 6, pp. 2065-2076, 2016.
[88]S. Ghatak and A. Ghosh, Observation of trap-assisted space charge limited conductivity in short channel MoS 2 transistor, Applied Physics Letters, vol. 103, p. 122103, 2013.
[89]J. M. Bernhard, Work Function Study of Iridium Oxide and Molybdenum Using UPS and Simultaneous Fowler-Nordheim IV Plots with Field Emission Energy Distributions, 1999.