Al-doped α-MnO₂ coated by lignin for high-performance rechargeable aqueous zinc-ion batteries

Abstract

Al3+ doping combined with lignin coating improves the structural stability and electrochemical performance of the modified α-MnO2, L + Al@α-MnO2.

Challenges and Perspectives for Doping Strategy for Manganese-Based Zinc-ion Battery Cathode

“…Interestingly, Al-doped MnO 2 exhibited a sea urchin-like morphology with a size of 4.5-5.0 µm and an enlarged interlayer spacing (0.24 nm vs. 0.29 nm). Xiong et al reported that Al-doped α-MnO 2 coated with lignin was formed through a hydrothermal reaction involving KMnO 4 , NH 4 F, Al 2 (SO 4 ) 3 , and lignosulfonate at 200 • C, as illustrated in Figure 2a [44].…”

Lignin-Based Materials for Sustainable Rechargeable Batteries

“…The use of lignin-coated PEDOT in LIB displayed the highest specific capacity in the first cycle, but a better rate capability was confirmed in NIB. Lignin was also used in a Zn-ion battery (ZIB) [108][109][110]. ZIB has attracted attention because of its non-toxicity, high safety, high theoretical capacity of zinc (820 mAh g −1 ), and outstanding rate capability [111,112].…”

“…However, ZIB has the limitation of the dissolution of transition metal from the cathode (i.e., Mn 2+ ) and forming of zinc hydroxide sulfate (ZHS), which causes a loss of capacity [113]. To suppress them, Lignin-coated a-MnO 2 nanorods and nanowires with Al 3+ dopant were synthesized with NH 4 F, Al 2 (SO 4 ) 3 , KMnO 4 , and sodium lignosulfonate using a hydrothermal method (Figure 10a) [110]. The MnO 2 with lignin shows 1D nanorods providing large reaction sites (Figure 10b).…”

“…In comparison, the Se cathode without lignin retained only 60% of initial capacity (~180 mAh g −1 ) after 300 cycles. To investigate the effect of lignin on the polarization, we compared the chargedischarge profiles, as shown in Figure 12a-d [107,110,116]. Overall, the addition of lignin did not significantly influence the polarization.…”

Stability Optimization Strategies of Cathode Materials for Aqueous Zinc Ion Batteries: A Mini Review

“…As shown in Figure 1D , the MZHCF (MZHCF-7) with Mn content of 7% retained 94% of the initial capacity (far more than 17% of ZnHCF) after 500 cycles at 0.25 Ag −1 , displaying a significant synergistic optimization effect. In addition, the gap doping of heteroatoms (especially metals with similar ion radius) has been proved to effectively stabilize the phase transition structure and inhibit the dissolution of materials, which contributes to improving the reversibility of cathodic electrochemical reaction ( Xu et al, 2021a ; Chen et al, 2021 ). Moreover, Wang et al obtained multivalent cobalt (Co 2+ , Co 3+ )-doped Mn 3 O 4 nanosheets (Co-Mn 3 O 4 /CNA) based on carbon nanosheets array by electrodeposition on the basis of Co-MOF precursors prepared in water bath and annealing ( Ji et al, 2021 ).…”