為了滿足高效，可持續和經濟的水分解電催化劑的急切需求，使用一種簡便且單步驟快速（10分鐘）微波水熱法製備了摻鈉的氧化鉬（MoO3）。不同的合成參數極大地影響了晶體奈米結構，最終控制了整個電催化分解水中水氧化（OER, Oxygen Evolution Reaction性能。在合成方法中，改變（NH4.6Mo7O24.4H2O和Na2MoO4.2H2O作為前驅物，發現MoO3奈米結構的相和形態為h-MoO3奈米棒（晶體尺寸386Å）和α-MoO3-奈米晶（晶體尺寸200Å）。本研究發現並探討MoO3的奈米結構變化對合成參數變化和Na摻雜及其對電化學性能的相關性。 20％的Na摻雜造就了顯著氧空位的產生，差排密度（線/ 平方公尺）提高約20％，晶格應變提高10％，而在MoO3-晶胞“ c”軸的Mo = O鍵長中貢獻了顯著作用認為是MoO3夾層。 XPS光譜用於進一步確認和分析摻雜效果。因此，將鈉摻雜的α-MoO3奈米帶（微晶尺寸為183Å）滴附到Ni泡沫基材上並應用於OER電池應用，最低OER過電位為234mV（在最大電流密度為50mA/cm-2時），Tafel斜率為45mV/ dec，最後有36小時的高耐久性記錄。

Toward satisfying the surging demand of an efficient, sustainable and economic electrocatalyst for water splitting, Na doped molybdenum oxide (MoO3) was prepared by a facile one-step scalable rapid (10 minutes) microwave hydrothermal approach. Different synthesis parameters were greatly affected the crystalline nanostructures which eventually governed the overall OER performances. In the synthesis approach, due to varying (NH4).6Mo7O24.4H2O and Na2MoO4.2H2O as precursor, the phase and morphologies of the MoO3 nanostructure were found as h-MoO3 nanorods (crystallite size of 386Å) and α-MoO3-nanobelts (crystallite size of 200Å), respectively. The insight of nanostructural change in MoO3 for synthesis parameters variation and Na doping and their corresponding effect in electrochemical performances were reported. 20% Na-doping endowed significant contribution in Mo=O bond length of the “c” axis of MoO3-unit cell, by resulting significant oxygen vacancies with around 20% higher dislocation density (lines/m2), and 10% higher lattice strain thoughout the MoO3-interlayers. Raman spectra was utilized to disclose the phase modification and vibration signature estimation for parameters for MoO3 nanostructure synthesis. The shifting, sharping, broadening and intensity variation of the characteristic Raman peaks at 816cm-1 and 995cm-1 also indicated the distorting of the MoO3 interlayer and corresponding vacancy defect as found in XRD. Finally, the resulted modification in the elementary compositions and binding energies for synthesis parameters variation and doping was determined by XPS to explain their corresponding effect in OER. The effect of synthesis parameters of MoO3 also made a great contribution in OER performance, such as for precursor types variation the ECSA was shifted from 12.2 to 24.5 mA/cm2, where the tafel slopes were found to be reduced from around 60 to 45 mV/dec. In addition, for precursor concentration variation the ECSA was improved around 2 folds (from 24.5 to 44.6 mA/cm2) with a waning of the tafel slope from 56 to 41 mV/dec. For various dopant concentrations, up to 0.6% Na ions were successfully inserted within the MoO3 interlayers by endowing as significant oxygen vacancies effect. The Na-doped α-MoO3 nanobelts (crystallite size of 183Å) casted onto Ni-foam substrate for OER cell application and resulted the significant improvement in ECSA from 24.5 to 42.5 mA/cm2 with OER overpotential, from 246 to 234mV, at maximum current density 50mAcm-2. Thus suggesting that the dopant endowed great modification of MoO3 interlayer with favorable geometry, morphology, oxygen vacancy, and active sites which upturned the OER performance by favoring the better water molecule contact and charge transfer resistance. The cell was recorded to be stable until 3000cycles (as-synthesized:244mV to after 3000 cycles: 251mV) with higher durability of 36 hours.

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