Reasonable design of high-activity catalytic sites for reducing the activation energy barrier of O–H bonds is significant for efficient conversion of hydrogen energy involving water dissociation. Herein, a coupling oxygen vacancy (V_O) strategy for intensifying generation and transfer of photo-induced electron for enhancing catalytic activity of water dissociation is verified. Using ammonia borane hydrolysis as a verification, the turnover frequency of Ru-TiO₂-V_O (Ru-TV_O) catalyst reaches up to 1614 min⁻¹ in visible light excitation condition at 298 K, exceeding the highest activity in Ru-based catalysts. Intensified generation and transfer of photo-induced electron via coupling V_O reduces the activation energy barrier of O–H bond on Ru sites, leading to a boosted intrinsic activity of Ru toward water dissociation. Ru sites enriched by photo-induced electrons also exhibit unprecedented performance in phenylacetylene hydrogenation. This work provides an effective strategy for water dissociation through V_O-intensified generation and transfer of photo-induced electron in the field of energy conversion.

Electrolysis of water splitting is a clean and sustainable method for hydrogen production without the consumption of fossil fuels or the emission of carbon dioxide. Although a series of non-precious metal catalysts have been developed, they still cannot match the performance of precious metal catalysts in water electrolysis. Ruthenium (Ru), as a noble metal with an ideal cost-to-performance ratio and stable activity, is widely utilized by researchers. However, Ru-sites of electrocatalysts still face several challenges, such as size optimization, structural instability, and electronic structure regulation. This article reviews the design strategies on engineering Ru-based electrocatalysts for efficient water electrolysis, such as atomic-level dispersion, alloying, framework effect, doping, defect engineering, and interface design. And the application progress of precious metal catalysts in the seawater electrolysis was further reviewed and analyzed. These design strategies and their unique advantages provide a valuable theoretical foundation for the future application of Ru-based catalysts in hydrogen production via water electrolysis.

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.

The dissociation of water is the rate-determining step of several energy-relating reactions due to high energy barrier in homolysis of H-O bond. Herein, engineering vacancy-atom ensembles via injecting oxygen vacancy (V_O) into single facet-exposed TiO₂-Pd catalyst to form V_O-Pd ensemble is proposed and implemented. The outstanding activity of as-prepared catalyst, 1.5-PdTV_O, toward water dissociation is established with a turnover frequency of 240 min⁻¹ in ammonia borane hydrolysis at 298 K. Density functional theory simulation suggests that the V_O-Pd ensemble is responsible for the high intrinsic catalytic activity. Water molecules tend to be dissociated on V_O sites and ammonia borane molecules on Pd atoms. Those H atoms from water dissociation on V_O combine with H atoms from ammonia borane on Pd atoms to generate H₂. This insights into engineering vacancy-atom ensembles catalysis provide a new avenue to design catalytic materials for important energy chemical reactions.

Metal nanoparticles and metal oxides promisingly provide different catalytic active sites at their interfaces. Constructing high-density interfaces is essential to maximize synergies. Herein, a Cu–Co₃O₄ nanoparticles interfacial structure produced via pyrolysis and moderate oxidation from metal-organic frameworks has been designed to boost the intrinsic activity. The Cu–Co₃O₄ nanoparticles composites exhibit a turnover frequency of 57.5 min⁻¹ for ammonia borane hydrolysis, far higher than those of monometallic Cu and Co₃O₄ nanoparticles, showing the synergistic effect of Cu and Co₃O₄ nanoparticles at their interface. Density functional theory calculations and in situ Raman spectroscopy reveal the catalytic mechanism of dual active sites, in which Co₃O₄ nanoparticles at Cu–Co₃O₄ interface efficiently bind and activate water molecules and Cu nanoparticles easily activate NH₃BH₃ molecules. This study opens up a new pathway for achieving high-efficiency noble metal-free catalysts for hydrogen generation and other heterogeneous catalysis.

Boron hydrides release an abundant amount of hydrogen in the presence of a suitable catalyst. Accelerating bimolecular activation kinetics is the key to designing cost-effective catalysts for borohydride hydrolysis. In this study, the bimolecular activation of a polar O–Co–P site demonstrated superior hydrogen-generation kinetics (turnover frequency, TOF = 37 min⁻¹, 298 K) and low activation energy (41.0 kJ mol⁻¹) close to that of noble-metal-based catalysts. Through a combination of experiments and theoretical calculations, it was revealed that the activated dangling oxygen atom in the Co–O precursor effectively replaced via surface-phosphorization because of strong electronic interactions between the dangling oxygen and P atoms. This substitution modulated the local coordination environment and electronegativity around the surface Co sites and formed a new polar O–Co–P active site for optimizing the activation kinetics of ammonia borane and water. This strategy based on bimolecular activation may create new avenues in the field of catalysis.

Bismuth-based compounds with high capacity and durability are still challenging in Li-ion batteries (LIBs). In this article, Bi₂S₃ nanorods hosted on reduced graphene oxide nanosheets (Bi₂S₃/rGO, BSG) are successfully prepared using molecular precursor pyrolysis strategy. 1D nanorod architecture possesses preeminent kinetic characteristics, shortening the ion diffusion path and increasing the contact area between electrode and electrolyte. The large specific surface area and charge polarization of rGO at the interface promote charge transfer. The capacity of material (BSG-400) reaches 558.4 mAh g⁻¹ at 0.2 A g⁻¹ after 200 cycles. The anode properties of the composite outperform those of pristine Bi₂S₃. The introduction of graphene enables the interfacial interaction between rGO and Bi₂S₃. The closely contact interface improves the conductivity and lithium storage performances of Bi₂S₃. The regulatory effect of rGO on the electronic density of states and band gap of Bi₂S₃ has been demonstrated by theoretical calculation. The synthetic approach has the advantages of universality, simple operation procedure, and strong repeatability. This research provides some ideas for the preparation of other metal sulfides/rGO nanomaterials and their application in battery research.

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.