@article{Peng_Chen_Zhang_Zhou_Gao_Wu_Liu_Liu_Hu_Chen_2021, title={Oxygen-Containing Functional Groups Regulating the Carbon/Electrolyte Interfacial Properties Toward Enhanced K+ Storage}, volume={13}, url={https://www.nmlett.org/index.php/nml/article/view/958}, DOI={10.1007/s40820-021-00722-3}, abstractNote={<p>Oxygen-containing functional groups were found to effectively boost the K<sup>+</sup> storage performance of carbonaceous materials, however, the mechanism behind the performance enhancement remains unclear. Herein, we report higher rate capability and better long-term cycle performance employing oxygen-doped graphite oxide (GO) as the anode material for potassium ion batteries (PIBs), compared to the raw graphite. The in situ Raman spectroscopy elucidates the adsorption-intercalation hybrid K<sup>+</sup> storage mechanism, assigning the capacity enhancement to be mainly correlated with reversible K<sup>+</sup> adsorption/desorption at the newly introduced oxygen sites. It is unraveled that the C=O and COOH rather than C-O-C and OH groups contribute to the capacity enhancement. Based on in situ Fourier transform infrared (FT-IR) spectra and in situ electrochemical impedance spectroscopy (EIS), it is found that the oxygen-containing functional groups regulate the components of solid electrolyte interphase (SEI), leading to the formation of highly conductive, intact and robust SEI. Through the systematic investigations, we hereby uncover the K<sup>+</sup> storage mechanism of GO-based PIB, and establish a clear relationship between the types/contents of oxygen functional groups and the regulated composition of SEI.</p> <p>Highlights:</p> <p>1 Oxygen functional groups improve rate capability as well as long-term cycling stability of graphite oxide.<br>2 The adsorption-intercalation hybrid K<sup>+</sup> storage mechanism of graphite oxide (GO) is elucidated by in situ Raman spectroscopy and systematic electrochemical characterization.<br>3 It is unraveled that the C = O and COOH rather than C-O-C and OH groups contribute to the formation of highly conductive, intact and robust solid electrolyte interphase.</p>}, journal={Nano-Micro Letters}, author={Peng, Yufan and Chen, Zhen and Zhang, Rui and Zhou, Wang and Gao, Peng and Wu, Jianfang and Liu, Hui and Liu, Jilei and Hu, Aiping and Chen, Xiaohua}, year={2021}, month={Sep.}, pages={192} }