半導體奈米異質結構之載子動力學與光催化反應

Charge Carrier Dynamics and Photocatalysis of Semiconductor Nanoheterostructures

魏佑宸(Yu-Chen Wei) ； 蒲盈志(Ying-Chih Pu)

《化學》 80卷3期 (2022/06) Pp. 285-296

https://doi.org/10.6623/chem.202206_80(3).011

摘要

降低二氧化碳於地球大氣層中的濃度而達到「氣候中和」與「淨零排放」，是全球密切關心的重要議題。利用半導體奈米異質結構進行光催化二氧化碳還原或水分解反應，不但能減輕溫室氣體對環境帶來的變異，產物亦可作為化學燃料或有價值的化學品再次利用，此產物亦稱為「太陽燃料」，在近年來吸引了諸多研究熱潮。半導體奈米異質結構的特性將決定其應用於光催化之活性，利用時間解析光譜技術，可分析半導體奈米異質結構經由能帶結構調控後，界面載子轉移及複合程序對於光催化反應之影響。臨場暫態吸收光譜技術，可即時探測半導體奈米異質結構與分子進行化學反應時，激發態載子的動力學模式。透過載子動力學研究，可建構出半導體奈米異質結構提升光催化活性之機制，以期未來實際應用於太陽燃料生產技術上。

關鍵字

半導體 ； 奈米異質結構 ； 載子動力學 ； 臨場暫態吸收光譜技術 ； 太陽燃料

並列摘要

The reducing of CO_2 concentration in the atmosphere of earth to achieve ＂climate neutral＂ and ＂Net Zero Emissions＂ is an important global issue. Semiconductor nanoheterostructures (NHSs) have been demonstrated the ability to reduce CO_2 or split H_2O into chemical fuel or valuable chemicals by photocatalytic processes, which also called solar fuel and was extensively investigated in the recent years. Since the intrinsic properties of semiconductor NHSs would dominate the activity in the application of photocatalysis, time-resolved spectroscopic technologies can be used to study the charge carrier transfer and recombination processes in semiconductor NHSs and the related effects in the photocatalysis. In-situ transient absorption spectroscopic measurements can real-time provide the charge carrier dynamics at the interface between semiconductor NHSs and molecules during the chemical reactions. The investigation of charge carrier dynamics can be used to build the mechanism behind the photoacticity improvement, promoting the realization of practically solar fuel production.

並列關鍵字

Semiconductor ； Nanoheterostructure ； Charge carrier dynamics ； In-situ transient absorption spectroscopy ； Solar fuel