An interfacial wetting water based hydrogel electrolyte for high-voltage flexible quasi solid-state supercapacitors

Recent advances in solid‐state supercapacitors: From emerging materials to advanced applications

“…A GPE prepared by a water plasticizer is specifically called a hydrogel polymer electrolyte. This type of water containing PEs, which is low‐cost and environmentally friendly, has a three‐dimensional polymeric network to trap water inside, mainly by surface tension 106‐109 . Among GPEs, PVA‐based hydrogels have so far been the most widely studied polymer matrix for SSCs applications.…”

Improving the performance of QSEDLCs by modulating the properties of electrolytes from bulk to interfaces

“…[1][2][3] However, the narrow electrolyte decomposition windows (EDWs), poor interfacial compatibilities between electrolytes and electrodes, fast self-discharge, and strong electrode thickness dependency of the aqueous GPE-based QSEDLCs severely restrict their applications in various fields. [4][5][6][7][8] As all these above-mentioned weaknesses are closely related to the properties of electrolytes, many strategies have been proposed to separately modulate the properties of electrolytes to improve the performance of the GPE-based QSEDLCs. 4,[8][9][10][11][12] For example, the ''water-in-salt'' electrolytes have been developed to increase the EDWs, 11,12 the polyzwitterion gel electrolytes have been prepared to suppress the self-discharge, 8,9 and a bottom-up method has been designed to weaken the electrode thickness dependency.…”

“…[4][5][6][7][8] As all these above-mentioned weaknesses are closely related to the properties of electrolytes, many strategies have been proposed to separately modulate the properties of electrolytes to improve the performance of the GPE-based QSEDLCs. 4,[8][9][10][11][12] For example, the ''water-in-salt'' electrolytes have been developed to increase the EDWs, 11,12 the polyzwitterion gel electrolytes have been prepared to suppress the self-discharge, 8,9 and a bottom-up method has been designed to weaken the electrode thickness dependency. 10 Despite significant progress, challenges remain to develop a strategy to improve the performance of the aqueous GPE-based QSEDLCs by addressing all these weaknesses simultaneously.…”

“…The deviation of the CV curves from the rectangular shape at high voltages is attributed to water decomposition. 4,8 The less significant deviation of the CV curve of the PPDP-Li + /Na + -based QSEDLC from the rectangular shape at the high voltages compared with the PPDP-Li + -based QSEDLC may be because the water activity of the former is lower than that of the latter (Fig. S6, ESI †).…”

“…4b, the Ragone plots show that the PPDP-Li + /Na + -PC-based QSEDLC has a better performance than some previously reported aqueous GPE-based QSEDLCs with different EDWs employing the activated carbon electrodes. 4,8,[21][22][23] In fact, in addition to the good electrochemical performance, the PPDP-Li + /Na + -PC-based QSEDLC also exhibits excellent flexibility and a high reversibility (Fig. S21 and S22, ESI †), demonstrating its promising applications in the field of flexible QSEDLCs.…”