Paradigm for swift dual single-atom stabilization on MBene using a CO2 laser in trifecta energy with ammonia production

Abstract

Dual single-atom (DSA) catalysts hold great potential, but their synthesis complexity remains a key challenge. Achieving strong interactions between single atoms (SAs) and the support is the main goal in SA catalysis for ensuring robust isolated SA–host interactions. To address this, we introduce a continuous-wave CO2 laser irradiation strategy that stabilizes SAs in 3 min and demonstrates the feasibility of MBene as a new two-dimensional borides host. Selective acid/oxidant etching expands delaminated MoAl1‐xB MBene sheets, exposing Mo-B rich basal planes, while L-tryptophan functionalized MoAl1‐xB immobilizes Co and Ni DSAs via electron-rich metal–N and metal–O sites under CO2 laser irradiation (λ = 10.6 μm, power = 25 W). The CoNi-DSA/MBene impressively increases electrochemical nitrate reduction reaction (NO3RR) activity, achieving an NH3 production rate of 32.36 ± 0.56 mg h−1 cm−2 at −0.8 V versus RHE. Experimental and theoretical studies confirm that unoccupied Co/Ni d-orbitals accept electrons from NO3−, while occupied d-orbitals donate charge to NOx p-orbitals, enhancing their electronic coupling with NO3−. This facilitates metal sites to decompose H2O, generating protons that migrate to NO3− intermediates, promoting hydrogenation for efficient NO3RR. Furthermore, Ar stripping/acid trapping was employed for NH3 collection to ensure practicality of NH3 production. Beyond NO3RR, CoNi-DSA/MBene is employed as the cathode in a Zn–NO3− battery, offering advanced energy solutions with NH3 production. This study underpins the potential of CO2 laser processing as a new avenue for the rational design of multifunctional SA catalysts in energy technologies.