Public anxiety and concern from cesium pollution in oceans have been back on the agenda since tons of nuclear waste water were announced to be poured into oceans. Cesium ion can easily enter organisms and bioaccumulate in animals and plants, thus its harm is chronic to humans through food chains. Here we showed a kind of hybrid ionic liquid membrane (HILM) for detection of cesium ion in seawater through CsPbBr₃ perovskite fluorescence. With sustainability in mind, HILM was built frugally. The lowest cost of HILM is below 3 cents per piece. The HILM can detect cesium ion quickly with eye-readable fluorescence signal. Ultracheap, portable, easy-to-use on-site detection device could offer benefit for personal security and applications in environment science and ecology in the future decades.

自从宣布将成吨的核废水倒入海洋以来，公众对海洋中铯污染的焦虑和担忧已经重新提上日程。铯离子很容易进入生物体内并在动植物体内蓄积，因此其通过食物链对人类的危害是慢性的。在这里，我们展示了一种混合离子液体膜 (HILM)，用于通过 CsPbBr ₃钙钛矿荧光检测海水中的铯离子。考虑到可持续性，HILM 以节俭的方式建造。HILM 的最低成本低于每件 3 美分。HILM 可以通过肉眼可读的荧光信号快速检测铯离子。超便宜、便携、易于使用的现场检测设备可以在未来几十年为个人安全以及环境科学和生态学中的应用带来好处。