本研究主要目標開發以鉑包覆金屬氧化物之新型核殼型觸媒，並應用於酸性條件下氧氣還原反應。實驗構想為利用金屬氧化物的半導體特性，運用光沉積法(Photodeposition Method)將鉑沉積於二氧化鈦上，並以合成氣氛、光強度及反應時間為變數，系統性地探討觀察所製備觸媒的形貌與負載量。更進一步，研究此新型核殼觸媒之氧氣還原反應活性與穩定性。
本合成首先分別在一般大氣及曝入飽和一氧化碳下進行光沉積，從UV-vis 光譜可得知，在合成過程中，曝入一氧化碳之溶液，會與鉑前驅物產生錯合離子。並從TEM 之影像觀察到，經曝入一氧化碳所製備的鉑樣品有明顯聚集現象；而在一般大氣下製備之樣品，可成功形成薄層鉑完整包覆二氧化鈦的核殼觸媒系統。由XAS光譜證實，經光沉積合成出來之樣品有著較飽滿的d 電子軌域，證實此觸媒系統有著強觸媒-載體交互作用(Strong Metal-Support Interaction, SMSI)，唯此效應會隨著觸媒聚集而降低。
從電化學角度來看，在大氣下合成形成鉑包覆二氧化鈦核殼結構的觸媒，不管是電化學活性面積還是氧氣還原活性，皆明顯優於曝入一氧化碳之樣品。而在大氣中光強度0.1 sun 沉積3 小時的樣品(起始電位= 0.86 VRHE)，其質量活性及電化學活性面積，均可比擬商業化白金Pt/C(起始電位=0.85 VRHE)的效能。更在五千圈後的穩定性測試，質量活性僅有55%的衰退，而商業化白金Pt/C 則衰退了79%，穩定性有著顯著的進步。

The main objective of this study is to develop a novel M@Pt(M= metal
oxide) core-shell catalyst for oxygen reduction reaction under acidic
conditions. The photodeposition method was adopted to deposit platinum
on titanium dioxide. Gas atmosphere, light intensity and reaction time
were used as variables to systematically investigate the morphology of
the prepared catalyst. Furthermore, the oxygen reactivity and stability of this novel core-shell catalyst were also examined in this study.
First, photodeposition was conducted both in air or an atmosphere filled with carbon monoxide. It is interesting to note that Pt-complex ions were observed in carbon monoxide atmosphere by UV-vis spectroscopy.As seen by TEM, the samples prepared under exposure to carbon monoxide have obviously aggregated Pt formation on TiO2 particles. On the other hand, TiO2@Pt core-shell catalyst could be successfully prepared in air by photodeposition, and XAS spectroscopy confirms that Pt in the samples synthesized under these conditions had less unfilled d-state, indicating the presence of Strong Metal-Support Interaction(SMSI).
For the electrochemical test, TiO2@Pt prepared in air exhibits a
higher electrochemical surface area or oxygen reduction activity, which
are significantly better than the counterpart synthesized under carbon
monoxide ones. TiO2@Pt prepared in air under light intensity 0.1 sun for 3 hours (onset potential = 0.86 VRHE) has the mass activity and
electrochemically surface area comparable to commercial Pt/C (onset
potential = 0.85 VRHE).Finally, the designed configuration with TiO2-core and Pt thin shell has made a significant progress in improving the stability of electrocatalysts for Oxygen Reduction Reaction (ORR). TiO2@Pt prepared in air under light intensity 0.1 sun for 3 hours experienced only degradation of 55 % in mass activity, whereby commercial Pt/C suffered a loss of 79% after 5000 cycles.

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