近年來，鎳鉬的氧化物被發現有利於電解尿素(UOR)及產氫，而被大量的使用在尿素電解上，利用摻雜、退火或與其他物質形成異質結構等不同的方式以鎳鉬的氧化物為基礎進行改變，皆有不錯的成果，而本研究則主要專注在摻雜上，嘗試將鐵、鈷等過渡金屬元素摻雜於鎳鉬的氧化物，來做為尿素分解的電極，發現摻雜後的電極，將可以改變電化學的結果。在經過XRD、Raman測量後，可以鑑別產物確為鎳鉬的氧化物，且在摻雜後並無結構上的改變，並且藉由EXAFS與擬合的結果，證明鐵、鈷取代了鎳的位置，在LSV、EIS等電化學方法測量後，發現摻雜了鐵，可以減少分解尿素時陽極的電位，而摻雜鈷時，卻會增加了陽極的電位，根據參考文獻，我們認為很有可能是因為摻雜的過程中，將可以改變鎳鉬氧化物的能隙，所以可以藉由摻入的金屬來調整載子在傳輸時候的速度，同時也改變了其電阻，因此，在適度與正確的摻雜上，的確可以藉由摻雜過度金屬離子來減少其尿素電解的電位，解決尿素汙染的同時伴隨著陰極反應產生乾淨的能源-氫氣。

Recently, nickel molybdenum oxide has been widely investigated for its potential application as a catalyst in the electrooxidation reaction of urea. Many researchers have used doping、annealing、and heterostructure forming to modify nickel molybdenum oxide as an electrode and achieved promising results. In this research project, we concentrated on the method of doping, using transition metals such as iron and cobalt as the dopant in the nickel molybdenum oxide electrode for electrooxidation of urea. We observed that the doped electrode can significantly change the electrochemical properties. From the XRD and Raman data, we can clearly see that the samples we prepared are indeed nickel molybdenum oxide and the crystal structure of the sample remains unchanged after doping. Our EXAFS results revealed that the iron and cobalt
dopant atoms substitute for nickel atoms in the samples. Furthermore, our electrochemical measurements such as LSV and EIS showed that the Fe-doped sample can lower the overpotential while the Co-doped sample increases the overpotential. We speculate that the overpotential changes may result from that doping transition metal could change and tune the band gap of nickel molybdenum oxide. Therefore, we can use transition-metal doping to modify and control the band gap and consequently change the carrier’s transport efficiency. In other words, transition metal doping in nickel molybdenum oxides can improve the electrooxidation of urea, solving the urea pollution problem and producing clean-energy hydrogen at the same time.

1. IEA-Energy related CO2 emissions, 1990-2019
https://www.iea.org/data-and-statistics/charts/energy-related-co2-emissions-1990-2019
2. GISS Surface Temperature Analysis
https://data.giss.nasa.gov/gistemp/graphs_v4/customize.html
3. 中華民國一百零九年、一百十年及一百十四年再生能源推廣目標、各類別再生能源所占比率如附表
https://www.moeaboe.gov.tw/ecw/populace/Law/Content.aspx?menu_id=8627
4. Ewelina Urbańczyk, Maciej Sowa & Wojciech Simka., Urea removal from aqueous solutions—a review, 2016.Journal of Applied Electrochemistry,46, p.1011–1029.
5. 脲酶活性中心的模擬
http://140.122.142.231/~wzlee/research.htm
6. Shuguang Shen 1, Meina Li, Binbin Li, Zhijun Zhao, Catalytic hydrolysis of urea from wastewater using different aluminas by a fixed bed reactor. Environ Sci Pollut Res Int., 2014. 21(21): p. 12563-8.
7. Ke Ye, Gang Wang, Dianxue Cao and Guoxiong Wang., Recent Advances in the Electro-Oxidation of Urea for Direct Urea Fuel Cell and Urea Electrolysis, Topics in Current Chemistry,2018, 376,42.
8. Kaibing Xu, Wenyao Li, Qian Liu, Bo Li, Xijian Liu, Lei An, Zhigang Chen, Rujia Zou and Junqing Hu,Facile synthesis of NiMoO4·xH2O nanorods as a positive electrode material for supercapacitors. Chemistry–A European Journal, J. Mater. Chem. A, 2014, 2, 4795.
9. Jingjing Yuan, Dachuan Yao, Ling Jiang, Yingrui Tao, Jianfei Che, Guangyu He, and Haiqun Chen.,Mn-Doped NiMoO4 Mesoporous Nanorods/Reduced Graphene Oxide Composite for High-Performance All-Solid-State Supercapacitor ACS Appl. Energy Mater.,ACS Appl. Energy Mater. 2020, 3, 1794−1803.
10. Zi-You Yu, Chao-Chao Lang, Min-Rui Gao, Yu Chen, Qi-Qi Fu, Yu Duan and
Shu-Hong Yu.,Ni–Mo–O nanorod-derived composite catalystsfor efficient alkaline water-to-hydrogenconversion via urea electrolysis .Energy &
Environmental Science, 2018. 11, 1890.
11. X光粉末繞射儀(XRPD)
http://nscric.site.nthu.edu.tw/p/404-1186-122163.php?Lang=zh-tw
12. Mao-Cheng Liu, Ling-Bin Kong, Chao Lu, Xue-Jing Ma, Xiao-Ming Li,Yong-Chun Luob and Long Kang.,Design and synthesis of CoMoO4–NiMoO4·xH2O bundles with improved electrochemical properties for supercapacitors, Journal of Materials Chemistry A,2013, 3, 16542.
13. Yuekui Xu, Haicheng Xuan, Jinhong Gao, Ting Liang, Xiaokun Han, Jing Yang, Yongqing Zhang, Hui Li, Peide Han & Youwei Du., Hierarchical three-dimensional NiMoO4-anchored rGO/Ni foam as advanced electrode material with improved supercapacitor performance, Journal of Materials Science, 2018. 53, p.8483–8498.
14. K. Chokprasombat, C. Sirisathitkul, P. Harding, S. Chandarak, and R. Yimnirun., Synchrotron X-Ray Absorption Spectroscopy Study of Self-Assembled Nanoparticles Synthesized from Fe(acac)3 and Pt(acac)2, journal of nanomaterials, 2012. 53, 758429.
15. Su, Hailin & Huang, Shun-Yu & Chiang, Yueh-Feng & Huang, J. & Kuo, Chien-Cheng & Du, Y. & Wu, Y. & Zuo, R.. (2011). Unusual high-temperature ferromagnetism of PbPd0.81Co0.19O2 nanograin film. Applied Physics Letters - APPL PHYS LETT. 99. 10.1063/1.3634070.