Institute of Chemicobiology and Functional Materials, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, 200 Xiao Ling Wei, Nanjing210094, China.
ACS Appl Mater Interfaces. 2022 Dec 7;14(48):53615-53626. doi: 10.1021/acsami.2c12777. Epub 2022 Nov 27.
Moisture-activated electric generators (MEGs) that harvest clean energy from atmospheric humidity offer exciting opportunities for upgraded energy conversions. However, it is challenging to obtain MEGs that are both easy to fabricate and of high output power, due to the requirement for particular functional materials and the cumbersome manufacturing process. Herein, a simple and general method is adopted to prepare MEGs with chemically gradient structures. As a specific example, a gradient distribution of citric acid was successfully constructed inside an A4 printer paper by asymmetric drying, which can generate a continuous voltage of tens of millivolts by ambient humidity, and even to volts (275 mV and 7.6 μA cm) under asymmetric humidity stimulation, and the maximum power density output was 2.1 μW cm. The driving force behind this energy conversion is a self-maintained ionic gradient created within the paper by the asymmetric ionization of gradient organic acids when exposed to gradient or nongradient humid air. This work broadens the class of materials and possibilities for the rapid development of MEGs, shedding new light on the revolution of generators that harvest green and sustainable energy for power generation.
从大气湿度中获取清洁能源的湿敏发电（MEG）为升级能量转换提供了令人兴奋的机会。然而，由于需要特殊的功能材料和繁琐的制造工艺，因此很难获得既易于制造又具有高输出功率的 MEG。在此，采用了一种简单而通用的方法来制备具有化学梯度结构的 MEG。作为一个具体的例子，通过非对称干燥成功地在 A4 打印机纸张内部构建了柠檬酸的梯度分布，该纸张可以通过环境湿度产生数十毫伏的连续电压，甚至在非对称湿度刺激下产生几伏特（275 mV 和 7.6 μA cm）的电压，最大输出功率密度为 2.1 μW cm。这种能量转换的驱动力是纸张内部由梯度有机酸的非对称离化在暴露于梯度或非梯度湿空气中时产生的自我维持的离子梯度。这项工作拓宽了材料的类别和 MEG 快速发展的可能性，为利用绿色可持续能源进行发电的发电机的革命带来了新的曙光。
