Rational design of highly active catalysts for breaking hydrogen-oxygen bonds is of great significance in energy chemical reactions involving water. Herein, an efficient strategy for the artificial atom (RuPd) established by d-orbital coupling and adjusted by oxygen vacancy (V_O) is verified for water dissociation. As an experimental verification, the turnover frequency of RuPd-TiO₂-V_O (RuPdTV_O) catalyst in ammonia borane hydrolysis reaches up to 2750 min⁻¹ (26,190 min⁻¹ based on metal dispersion) in the absence of alkali, exceeding the highest active catalysts (Rh-based catalysts). The d-orbital coupling effect between Ru and Pd simulates the outer electronic structure of Rh. Electron transfer from V_O to (RuPd) constructs an electron-rich state of active sites that further enhances the ability of the artificial atom to dissociate water. This work provides an effective electronic regulation strategy from V_O and artificial atom constructed by d-orbital coupling effect for efficient water dissociation.

The design of high-performance catalysts is the key to the efficient utilization of hydrogen energy. In this work, a PdCu nanoalloy was successfully anchored on TiO₂ encapsulated with carbon to construct a catalyst. Outstanding kinetics of the hydrolysis of ammonia borane (turnover frequency of 279 mol ${}_{{\mathrm{H}}_2}$∙min⁻¹∙mol_Pd⁻¹) ranking the third place among Pd-based catalysts was achieved in the absence of alkali. Both experimental research and theoretical calculations reveal a lower activation energy of the B–H bond on the PdCu nanoalloy catalyst than that on pristine Pd and a lower activation energy of the O–H bond than that on pristine Cu. The redistribution of d electron and the shift of the d-band center play a critical role in increasing the electron density of Pd and improving the catalytic performances of Pd_0.1Cu_0.9/TiO₂-porous carbon (Pd_0.1Cu_0.9/T-PC). This work provides novel insights into highly dual-active alloys and sheds light on the mechanism of dual-active sites in promoting borohydride hydrolysis.

Controllable pyrolysis of metal-organic frameworks (MOFs) in confined spaces is a promising strategy for the design and development of advanced functional materials. In this study, Co-Co₃O₄@carbon composites were synthesized via pyrolysis of a Co-MOFs@glucose polymer (Co-MOFs@GP) followed by partial oxidation of Co nanoparticles (NPs). The pyrolysis of Co-MOFs@GP generated a core–shell structure composed of carbon shells and Co NPs. The controlled partial oxidation of Co NPs formed Co-Co₃O₄ heterojunctions confined in carbon shells. Compared with Co-MOFs@GP and Co@carbon-n (Co@C-n), Co-Co₃O₄@carbon-n (Co-Co₃O₄@C-n) exhibited higher catalytic activity during NaBH₄ hydrolysis. Co-Co₃O₄@C-II provided a maximum specific H₂ generation rate of 5, 360 mL·min^-1·g_Co^-1 at room temperature due to synergistic interactions between Co and Co₃O₄ NPs. The Co NPs also endowed Co-Co₃O₄@C-n with the ferromagnetism needed to complete the magnetic momentum transfer process. This assembly-pyrolysis-oxidation strategy may be an efficient method of preparing novel nanocomposites.