因能源需求與環境污染議題與日俱增，世界各國皆積極開發低汙染之替代能源，眾多綠色能源中，藉太陽能進行光催化水分解為一取代化石燃料之展望，且光催化水分解亦可達零碳排放與零污染之特點。當前研究結果，白金與其他貴金屬表現出良好之光電流特性，然其價格十分昂貴，且地表富含量低，不利於大範圍商業化，故開發地表豐富之非貴金屬水分解催化劑為此替代能源應用之一大課題。本研究利乃用矽作為光催化水分解之基板，藉由矽半導體特性照光產生電子電洞對與合適之能帶位置，故選其為本研究之光陰極。
　　本研究更藉黃光微影製程技術與乾式蝕刻技術對矽表面進行改質，使其表面形成微米柱形貌，因表面粗糙度增加，可使光吸收率更進一步提升。本研究藉滴落塗布法(drop-casting)將共催化劑修飾於矽微米柱，改善矽基板光生載子動能不足之問題，降低電子電洞再結合率，並提升產氫效能。再藉由熱退火技術，成功將二硫化鎢(WS2)、二硫化鉬(MoS2)與兩者復合之異質結構(MoS2-WS2)修飾於矽微米柱。光電流量測則於模擬太陽光照射(100 mW/cm2)下，並藉標準氫電極電勢(reversible hydrogen electrode；RHE)為0 V下量測其光反應，其結果顯示於滴定量30 μL時MoS2-WS2於0 V vs. RHE下光電流高達25.92 mA/cm2，相較於WS2與MoS2 (8.18 mA/cm2、11.64 mA/cm2)具更好之效能表現。起始電壓亦達0.14 V vs RHE at 1 mA/cm2，且穩定性表現於酸性電解液中亦明顯優於未修飾之矽微米柱，並於反應10小時後依然維持67.7%之電性效率。

Due to the increasing demand for energy and environmental pollution, countries around the world are actively developing alternative energy sources with low pollution. Among many green energy sources, the use of solar energy for photocatalytic water splitting is a prospect of replacing fossil fuels, and photocatalytic water splitting can also be achieved no carbon emissions and no pollution. According to the current research results, platinum and other precious metals exhibit good photocurrent characteristics, but their cost high and rareness on earth. Therefore, the development of abundant non-precious metal catalysts is one of the major difficulties in replacing fossil fuels with this method.
　 In this study, silicon microwires (Si MWs) were fabricated by an inductively coupled plasma etching technique as the light absorber of solar hydrogen evolution. The three-dimensional structures of MWs enhanced the surface area and light harvesting ability to improve photoconversion efficiency. Molybdenum tungsten sulfide (MoxW1-xS2) was used as an Earth-abundant co-catalyst to decorated on Si MWs via drop-casting and thermal combustion methods for accelerating the sluggish kinetics of carriers on Si MWs. Various amount of Mo and W precursors were applied to synthesize of MoxW1-xS2 materials for optimizing the hydrogen adsorption energy. The optimal photocatalytic performance was achieved by MoWS2/Si photocathode with current density at 0 V (vs RHE) of -25.92 mA/cm2 and onset potential of 0.14 V (vs RHE).

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