Dendrite-free zinc anode enabled by zinc-chelating chemistry

Strategies of regulating Zn2+solvation structures for dendrite-free and side reaction-suppressed zinc-ion batteries

“…3d), the peaks of Zn–O pair were located at 3.14 Å for all electrolyte systems, whereas the sharp peak of Mg–O was located at 2.84 Å, implying that the binding interaction between Mg 2+ –H 2 O was much stronger than Zn 2+ –H 2 O, thus regulating the solvation sheath of Zn 2+ ions. In addition, this hypothesis could be further verified by the classic Eigen–Tamm mechanism; generally, there are two types of Zn 2+ -solvation-shell structures (SSIP, Zn 2+ (H 2 O) 6 SO 4 2− ; CIP, Zn 2+ (H 2 O) 5 OSO 3 2− ), 90,101 as always determined by Raman spectroscopy (Fig. 3e).…”

“…58 In addition, the regulated solvation shell and electrode interface ultimately inhibited zinc dendrites and other side reactions. Besides, a solvation structure regulation strategy based on chelating chemistry was proposed, 101 and 2-bis(2-hydroxyethyl) amino-2-(hydroxymethyl)-1,3-propanediol (BIS-TRIS) was introduced into ZnSO 4 as an electrolyte chelating additive. As proven in Fig.…”

“…This phenomenon further demonstrated that the coordination environment of Zn 2+ was regulated using the cheating agent BIS-TRIS. 101…”

“…The strategies of zinc-philic additives and the corresponding electrochemical performance are summarized in Table 3. 58,87,101,207–209,211,213,216–225 These zinc-philic additives can adsorb onto the zinc anode surface via physical/chemical adsorption to form a protective layer on the anode surface, which can effectively prevent the contact between H 2 O and zinc and guide the uniform zinc deposition. Besides, the adsorbed additive molecules promote the desolvation of Zn(H 2 O) 6 2+ by removing H 2 O molecules from the solvation sheath of Zn 2+ , which can suppress the HER, corrosion, and formation of by-products and zinc dendrites.…”

Reversible aqueous Zn battery anode enabled by a stable complexation adsorbent interface

“…[1][2][3][4][5][6] Nevertheless, Zn metal anode faces challenges in stability and reversibility in aqueous electrolyte, as exemplified by the uncontrolled dendritic-zinc growth and undesired corrosion side reactions, which have hindered the practical popularization of RAZBs. [7][8][9][10][11] To meet these challenges and enhance the electrochemical performance of Zn metal electrode, various methods, including three-dimensional structure design, [12][13][14] employing stable host, [15][16][17] surface protection, [18][19][20][21][22] and electrolyte engineering, [23][24][25] have been proposed for the recent years. Despite these exciting advances, it is still eagerly needed yet challenging to develop approaches with simple operation procedures and low-cost for practical aqueous Zn electrodes with satisfied reversibility.…”