Back Cover

The cover imageshows the heat charge/discharge process of layered Sr₃Fe₂O₇. The left side of the picture presents daytime, which means Sr₃Fe₂O₇ absorbs solar energy and releases O₂ to store chemical energy,while the right side of the imagepresents night, which means Sr₃Fe₂O₇ reacts with O₂ to release stored heat and generate electricity. [Correction added on 18 July 2023, after first online publication: Issue back cover has been incorrectly published in this issue and was published as Cover Picture of Volume 5 Issue 7.] image