21/08/2026
理大研發新一代高效耐用鈣鈦礦有機疊層太陽能電池 被遮擋仍能穩定運作 助推動薄膜太陽能技術工業應用
理大電機及電子工程學系能源轉換技術講座教授、鍾士元爵士可再生能源教授、理大智慧能源研究院副院長李剛教授領導的研究團隊，成功研發新一代鈣鈦礦有機疊層太陽能電池，不但發電效率高，更能有效抵抗負電壓帶來的損害。研究中的疊層裝置即使承受-40伏特的極端反向偏壓，仍能維持90%以上的初始效率，表現遠超現時所有薄膜太陽能技術，為薄膜太陽能技術走向實際應用邁出關鍵一步。
薄膜太陽能技術，例如碲化鎘（CdTe）、銅銦鎵硒（CIGS）、鈣鈦礦和有機太陽能電池等，具備輕巧、柔韌及低成本等獨特優勢。不過，這類材料有一個共通弱點：由於其「電子—離子混合導電」的特性，一旦太陽能電池被局部遮擋而產生負電壓，供電性能就難以保持穩定，組件甚至有機會受損。因此，能否抵抗反向偏壓，正是薄膜太陽能技術是否耐用及能否長期穩定運作的關鍵。
有機太陽能電池近年在效率和耐久度上都有長足進步，但科學界對它在反向偏壓下的實際表現，以及電荷在體異質結（即電池內部由兩種材料混合而成的發電活性層）如何傳輸，至今仍未完全掌握。填補這些空白的知識，正是推動薄膜太陽能技術實際應用不可或缺的一步。
團隊透過創新方法及策略性干預取得突破，透過抑制「供體—受體混合區」（即電池發電核心中，負責放出和接收電荷的兩種材料混合的區域）內孤立的受體簇，成功減少上述缺陷，研發出高效能的有機太陽能電池，其不可逆擊穿電壓更超過
-35伏特。換言之，只要負電壓不超過-35伏特，電池都不會被永久破壞，抗損能力大幅提升，為有機太陽能電池的效率和穩定性建立新標準。
是次研究顯示，透過抑制n-i-p型無機鈣鈦礦—有機疊層太陽能電池的「反向隧穿」（即太陽能電池被遮擋時電流反向流動、產生負電壓並損害電池的現象），有機太陽能電池成功保護鈣鈦礦層。即使承受-40伏特的極端反向偏壓，疊層裝置仍能維持90%以上的初始效率。此外，這些疊層太陽能電池非常穩定。在-20伏特下持續運作12小時後，仍保留90%初始效率；在-4.5伏特下持續運作2,000小時後，更保留高達 97% 的初始效率，表現遠超現時所有薄膜太陽能技術。
這項題為「具優異反向偏壓穩定性的鈣鈦礦—有機疊層太陽能電池」的研究成果已刊登於《自然材料》（Nature Materials）期刊。該研究詳述了體異質結有機太陽能電池中的反向電荷傳輸機制，並解決鈣鈦礦太陽能電池的反向偏壓不穩定問題，為發展穩定耐用的鈣鈦礦有機疊層太陽能電池提供關鍵指引。
新聞稿：https://www.polyu.edu.hk/tc/media/media-releases/2026/0720_polyu-develops-durable-shade-stable-perovskite-organic-tandem-solar-cells/
閱讀研究全文：https://www.nature.com/articles/s41563-026-02541-6
PolyU develops durable shade-stable perovskite–organic tandem solar cells, advancing thin-film solar technology application
A research team led by Prof. LI Gang, Associate Director of Research Institute for Smart Energy (RISE), Chair Professor of Energy Conversion Technology of the Department of Electrical and Electronic Engineering, Sir Sze-yuen Chung Professor in Renewable Energy, has successfully developed a new generation of perovskite–organic tandem solar cells (POTSCs) that not only deliver high power-generation efficiency but also effectively resist the damage caused by negative voltage. Even under an extreme reverse-bias of –40 V, the tandem devices retain more than 90% of their initial power-generation efficiency, far surpassing all existing thin-film solar technologies, marking a key step towards the practical application of thin-film solar technology.
Thin-film solar technologies, such as cadmium telluride (CdTe), copper indium gallium selenide (CIGS), perovskite and organic solar cells, offer the distinct advantages of their light weight, flexibility and cost-effective manufacturing. However, these materials share a common weakness: owing to their electron–ion hybrid conducting properties, once a solar cell is partially shaded and generates negative voltage, its sustained performance becomes difficult and components may even be damaged. The ability to resist reverse bias is therefore key to determining whether thin-film solar technology is durable and capable of stable, long-term operation.
Organic solar cells (OSCs) have made significant strides in both efficiency and durability in recent years. Yet their behaviour under reverse-bias condition and underlying charge transport mechanisms in bulk heterojunctions (the power-generating active layer inside the cell, formed by blending two materials), remains largely unexplored by the scientific community. Filling the related knowledge gaps is an indispensable step towards the practical application of thin-film solar technology.
The team achieved a breakthrough through its innovative approaches and strategic interventions. By suppressing isolated acceptor clusters within the donor-acceptor intermix region (the area at the power-generating core of the cell where the two materials responsible for releasing and receiving charges are blended), the team successfully minimised the above-mentioned defects and developed high-performance OSCs with an irreversible breakdown voltage exceeding -35 V. In other words, as long as the negative voltage does not exceed -35 V, the cell will not be permanently damaged. This substantially enhances damage resistance and establishes a new benchmark for the efficiency and stability of OSCs.
The study shows that, by suppressing reverse tunnelling (the phenomenon whereby, when a solar cell is shaded, current flows in reverse, generating negative voltage and damaging the cell) in n-i-p inorganic perovskite-organic tandem solar cells, the organic solar cells successfully protect the perovskite layer. Even after exposure to an extreme reverse-bias of -40 V, the tandem devices retained more than 90% of their initial efficiency. Moreover, these tandem solar cells proved highly stable: after continuous operation at -20 V for 12 hours, they retained 90% of their initial efficiency; and after continuous operation at -4.5 V for 2,000 hours, they retained as much as 97% of their initial efficiency - far surpassing all existing thin-film solar technologies.
The research has been published in the paper “Perovskite–organic tandem solar cells with superior reverse-bias stability,” in Nature Materials. The study provides a comprehensive understanding of reverse charge transport mechanism in bulk heterojunctions organic solar cells, overcoming reverse-bias instability in perovskite-based solar cells and providing critical guidelines for developing robust POTSCs.
Press Release: https://www.polyu.edu.hk/en/media/media-releases/2026/0720_polyu-develops-durable-shade-stable-perovskite-organic-tandem-solar-cells/
Full paper: https://www.nature.com/articles/s41563-026-02541-6
