Alternate-stacked Li4Ti5O12 nanosheets/d-Ti3C2 flexible film as a current collector-free, high-capacity and robust cathode for rechargeable Mg batteries

• Rechargeable magnesium batteries (RMBs) have gained increasing attention owing to its high volumetric capacity, crust abundance, and safety from dendrite-free characteristic. However, the lack of development of high-performance cathode materials with long cycling stability and satisfactory capacity has greatly restricted the development of RMBs. Herein, a self-supported, current collector-free and soft electrode is prepared with delaminated Ti3C2 (d-Ti3C2) and Li4Ti5O12 nanosheets by simple vacuum filtration as flexible cathode in RMBs. Fabricated into a full cell with hybrid AlCl3/MgCl2/Mg(TFSI)2 electrolyte and Mg anode (a thin Mg foil with thickness of 50 μm), the flexible cathode shows high initial specific capacity of 320 mAh g−1 at 20 mA g−1, excellent cycling stability (good retention even after 1000 cycles) and outstanding rate performance. Detailed mechanistic studies reveal that introduction of d-Ti3C2 provide fast transport paths for electrons and Mg2+. The enlarged layer spacing of composited d-Ti3C2 accounts for significant increment in capacity. Benefiting from above-mentioned advantages, the best performance among Ti-based electrode materials is realized and make wearable devices powered by RMBs possible, thus circumventing the safety issues of lithium batteries.

Subject headings

NATURVETENSKAP  -- Kemi -- Materialkemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Materials Chemistry (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Annan elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Other Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

2D materials

flexible electrodes

long-term cycling

Mg batteries

MXenes

Publication and Content Type

ref (subject category)

art (subject category)