Confining Perovskite Quantum Dots in Nanofluidic Channels to Enable Ultrahigh Light-Powered Ion Pumping

Biological ion pump that moves ion transport against a thermodynamic gradient is essential for many life activities such as neurotransmission, muscle contraction and photosynthesis. However, the fabrication of an analogous synthetic system with a high-performance remains a challenge. Here, the use of confined CsPbBr₃ perovskite quantum dots (QDs) in the nanofluidic channels of an anodized aluminum oxide membrane to achieve an ultrahigh light-powered ion pumping is reported. The oleic acid ligands of CsPbBr₃ QDs determine the cationic selectivity of nanofluidic channels, which enables a surface-charge-governed ion transport property. The optoelectronic effect of perovskite QDs creates a potential difference across the membrane under visible light irradiation. This potential difference reverses the spontaneous ion transport direction, and pumps the cation transport against a concentration gradient as high as 50-fold. The confinement of perovskite QDs within nanofluidic channels provides an alternative way for the building of light-powered synthetic ion pumps with a high pumping performance.