本研究以第一原理計算探討異質介面最穩定的介面結構、電子結構與電子傳輸的過程，其主要分為三個部分進行探討。
第一部份為金屬奈米粒子與氧化物半導體結合形成異質結構，其中氧化物有氧化鋅(ZnO)、氧化鋅錫(ZTO)與二氧化鈦(TiO2)，金屬奈米粒子為Ag13、Au13與Pt13。根據吸附能計算結果說明金屬奈米粒子吸附於氧化物為穩定異質結構；以電子結構而言，所有的異質結構NP/ZnO(002)、NP/ZTO(001)、NP/TiO2(001)與NP/TiO2(101)中，金屬奈米粒子會使原本半導體性質的本質氧化物轉變為導體性質，其中NP/TiO2(001) 與NP/TiO2(101) 會有自旋極化及磁性現象；而電荷轉移方面主要發生在NP與氧化物介面之間，NP/ZnO(002)與NP/TiO2(001)的穿隧能譜相較於本質的氧化物會有較高的穿隧係數，NP/ZTO(001)與NP/TiO2(101)系統穿隧係數則下降。
第二部份為不同尺寸的金奈米粒子Au13、Au38與Au62與二硒化鎢(WSe2)結合，分別將金奈米粒子與WSe2優化後，藉由調控吸附距離分別計算出Au13 / WSe2，Au38 / WSe2和Au62 / WSe2系統的最穩定的吸附距離為4.5、6.25和6.5Å，其相對應的吸附能分別為-5.05，-6.20和-10.29 eV；在金奈米粒子吸附下，WSe2從p型轉變為本徵或n型半導體，在費米能級附近存在許多平帶，平帶由金原子所產生；並藉由機械學習在不同的吸附距離和金奈米粒子尺寸下預測能量值與費米能量的電子狀態。
第三部份為Au13與MgP分子吸附於WSe2，計算出MgP/WSe2與Au13/ WSe2異質結構的吸附能分別為-1.78與-7.40 eV，為穩定異質結構；與本質WSe2的相比，在電子結構方面MgP會影響靠近費米面的價帶與導帶的能帶形狀並產生稍微平坦的能帶，Au13吸附會使本質的WSe2原本為p型半導體能帶移動接近本質半導體，Au13則在WSe2能隙中貢獻局域性較高的電子狀態，MgP/WSe2與Au13/ WSe2其能態密度電子自旋向上與自旋向下形狀皆為對稱，不具有磁性行為；在電性傳輸部分，MgP/WSe2在導帶區間穿隧係數相較於本質WSe2有增加，Au13/WSe2對於導帶和價帶區間的穿隧係數皆下降。WSe2、MgP/WSe2 與Au13/ WSe2系統在能量大於1.25 eV偏振光的照射下會產生光電流，WSe2在線偏振光的作用下左電極的與右電極所接收到的電子流為等量，而自旋流在自旋向上與自旋向下則為不等量，而在左右旋偏振光的照射下，左右電極所接收到的電子流為不等量，其自旋流在自旋向上與自旋向下則為不等量；MgP/WSe2 與Au13/WSe2系統在線偏振與圓偏振光的照射下，左右電極所接收到的電子流與自旋流皆為不等量。

Nanoparticles exhibiting quantum confinement effects are an ideal model system for studying the basic physical and chemical properties of nanostructure materials. When nanoparticles are supported on oxides or low dimensional materials, the interaction between the nanoparticles and the surface will affect the pristine performance of these materials and adjust their behavior. In this work, we investigate the geometric structures, electronic and transport properties of NP/oxides and Aun/WSe2 heterostructures based on first-principles calculation. In NP/oxides system, compared with pristine oxides, Ag13/ZnO, Au13/ZnO and Pt13/ZnO systems have more density of states at the Fermi level. However, the density of states of Ag13/ ZTO and Au13/ ZTO and Pt13/ZTO systems at the Fermi level are declining. When the NPs are adsorbed on the TiO2, spin polarization occurs. According to transmission spectrums, NP/ZnO(002) and NP/TiO2(001) systems have higher transmission coefficient than pristine oxide. Therefore, in NP/ZTO(001) and NP/TiO2(101) systems, they have a lower transmission coefficient than pristine oxide. As different sizes of gold nanoparticle absorb on the WSe2 monolayer transforms from a p-type to an intrinsic semiconductor, with few flat band around the Fermi level, which can reduce its conductance. Au adsorbs through the conduction and valence band intervals, the transmission coefficients are declining.

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