Additive‐Free Nb₂O₅−TiO₂ Hybrid Anode towards Low‐Cost and Safe Lithium‐Ion Batteries: A Green Electrode Material Produced in an Environmentally Friendly Process

Abstract

The development of additive‐free electrodes based on low‐cost and environmentally friendly materials is one of the major challenges for expanding sustainable and ecologically friendly energy storage. Most conventional electrode preparation processes are currently facing a problem: the addition of various additives/chemicals, particularly binder, carbon black and toxic N‐Methyl‐2‐pyrrolidone. These additives increase the production cost, decrease the energy and power density of the battery and are environmental hazards. Herein, a Nb2O5−TiO2 hybrid electrode for lithium‐ion batteries is fabricated by adopting the advanced radio frequency sputtering technique, which requires no supplementary support from additives/chemicals. The Nb2O5−TiO2 electrode reveals high capacity (gravimetric: 214 mAh g−1 at 50 mA g−1; areal: 0.0214 mAh cm−2 at 5 μA cm−2; volumetric: 1,813 mAh cm−3 at 5 μA cm−2), long‐term cyclic stability (gravimetric: 174 mAh g−1 at 0.4 A g−1; areal: 0.0174 mAh cm−2 at 40 μA cm−2; volumetric:1,474 mAh cm−3 at 40 μA cm−2 after 1000 cycles) and superior rate capability (gravimetric: 115 mAh g−1 at 6.0 A g−1; areal: 0.0115 mAh cm−2 at 6 mA cm−2; volumetric: 974 mAh cm−3 at 6 mA cm−2), which are better than other reported systems. Such a green chemistry strategy of fabricating additive‐free electrodes opens up new ways for the development of sustainable and robust energy storage technologies.

Huge Lithium Storage in 2D Bilayer Structures with Point Defects

“…Ideally, lithium metal as an anode material shows the highest specific capacity of 3860 mA h g –1 . , Regardless, the use of lithium metal as an anode is limited due to dendritic growth during charge–discharge cycling. Potential alternative hosts, such as silicon, , black phosphorous, metal sulfides, and metal oxides, − with high storage capacity were explored both theoretically and experimentally. , Despite the volume change during lithiation/delithiation, , a significant improvement in the performance of the silicon-based anodes was reported. − In the case of metal oxides or sulfides, the intercalation potential is relatively high and they exhibit low practical reversible capacity …”

Nb2O5 nanotubes on carbon cloth for high performance sodium-ion capacitors

“…(2) where x represents the stoichiometric number of sodium ions, similar to those in LICs, LIBs, sodium ion and potassium ion batteries [33][34][35][36][37][38][39][40].…”

Sodium‐Ion Capacitors: Recent Development in Electrode Materials

“…Recently, the charge storage based on pseudocapacitance, which arises at the electrode surfaces upon charge transfer, has been proved to be efficient for enhancing the rate capability of target electrode materials [6,30–33] . Nanostructure fabrication on electrode materials endowed conductive pathways can significantly improve the transport of ions and electrons, thereby leading to enhanced electrochemical performance [34–39] .…”