Advancing energy development with MBene: Chemical mechanism, AI, and applications in energy storage and harvesting

As global energy demands surge and fossil-fuel reserves shrink, next-generation 2D materials are racing to deliver ultrahigh capacity, ultrafast kinetics and rock-solid stability. Now, researchers from Henan University, Shanghai Jiao Tong University and the Chinese Academy of Sciences—led by Dr Jai Kumar, Dr Zhuanpei Wang and Prof Xiaowei Yang—have published a panoramic review on MBene, the boron-based sibling of MXene, that charts a direct route from wet-lab synthesis to AI-guided device deployment. The work offers a one-stop roadmap for harnessing MBene in batteries, supercapacitors, CO₂ electro-reduction and ammonia electrosynthesis.

Why MBene Matters
• Metallic conductivity & ceramic-like robustness – 200–320 GPa Young’s modulus and 5 eV cohesive energy outclass graphene and phosphorene.
• Tunable 0–0.5 eV diffusion barriers for Li⁺, Na⁺, Mg²⁺, Ca²⁺ – enable 5 C charging without plating or dendrites.
• Boron-rich surface – delivers selective N₂-to-NH₃ and CO₂-to-CH₄ catalysis while suppressing H₂ side-reactions.
• Etch-friendly MAB precursors – allow fluorine-free, NaOH-based delamination for green, gram-scale production.

Innovative Design & Features
• Structural palette: ortho-MBene, hex-MBene, tetr-Mo₂B₂, tri-Mo₂B₂ and vacancy-engineered Mo₂B_2-x.
• Surface terminations: –O, –S, –Cl, –Br and in-situ N-doping modulate work-function (4.2–5.1 eV) and ion affinity.
• Layer-number control: mono- to tri-layer flakes balance 450 m² g^-1 SSA vs long-cycle restacking resistance.
• Hybrid scaffolds: MBene/CNT, CoO/MBene and S-anchored MBene aerogels push areal capacity beyond 12 mAh cm^-2.

Applications & Future Outlook
• Multi-metal-ion batteries: 3377 mAh g^-1 (CrB₄-Ca), 923 mAh g^-1 (Mo₂B-Mg), 797 mAh g^-1 (Ti₂BN-Na) and 144 mAh g^-1 (MoB-Li) at ≥2 A g^-1 for 1000 cycles.
• Li–S chemistry: shuttle-free 86 % retention after 1000 cycles at 15 mg cm^-2 sulfur loading via B-, O-, F-active sites.
• Supercapacitors: 2006 mF cm^-2 (1/24-MoAl_1-xB) with 80 % retention after 5000 cycles in aqueous Na₂SO₄.
• CO₂RR & NRR: overpotentials down to –0.13 V (CrB-NH₃) and –0.45 V (MoB₂-CH₄) rival Cu and Ru benchmarks.
• AI acceleration: machine-learning models trained on 10⁴ DFT data points now predict stable MAB phases and surface terminations within seconds, slashing trial-and-error by 90 %.

Challenges & Opportunities
The review pinpoints scalable CVD growth, ambient-stability coatings, in-line spectroscopic QA, and hybrid AI-robotic synthesis as the next milestones to move MBene from benchtop breakthrough to gigafactory reality.