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Palladium hydride (PdHx) is one of the well‐known electrocatalytic materials, yet its synthesis is still a challenge through an energy‐efficient and straightforward method. Herein, we propose a new and facile cyanogel‐assisted synthesis strategy for the preparation of PdH0.649 at a mild environment with NaBH4 as the hydrogen source. Unlike traditional inorganic Pd precursors, the unique Pd−CN−Pd bridge in Pdx[Pd(CN)4]y ⋅ aH2O cyanogel offers more favourable spatial sites for insertion of H atoms. The characteristic three‐dimensional backbone of cyanogel also acts as a support scaffold resulting in the interconnected network structure of PdH0.649. Due to the incorporation of H atoms and interconnected network structure, the PdH0.649 achieves a high half‐wave potential of 0.932 V, a high onset potential of 1.062 V, and a low activation energy, as well as a long‐term lifetime for oxygen reduction reaction. Theoretical calculation demonstrates a downshift of the d‐band centre of Pd in PdH0.649 owing to the dominant Pd−H incorporation that weakens the binding energies of the *OH intermediate species. Zn‐air batteries (ZAB) based on PdH0.649 exhibits high power density, competitive open circuit voltage, and good stability, exceeding that of commercial Pt black. This work not only opens up a new avenue for the development of high‐efficiency Pt‐free catalysts but also provides an original approach and insight into the synthesis of PdHx. [ABSTRACT FROM AUTHOR]

2D MoS2 is acknowledged as a potential alternative to Pt‐based catalysts for hydrogen evolution reaction (HER) due to its suitable *H adsorption energy. However, the weak water adsorption capacity of MoS2 in an alkaline solution limits its performance improvement toward HER. Herein, a novel rare‐earth Tm single atoms decorated MoS2 (Tm SAs‐MoS2) catalyst is proposed, and the key role of Tm SAs on the enhanced HER performance of MoS2 is identified. It is verified that the Tm‐site in MoS2 contributes to the asymmetric [Mo‐S‐Tm] unit site, which serves as the electron donor to disturb the electronic state and accelerate electron accumulation at surrounding Mo‐S site. The obtained Tm SAs‐MoS2 exhibits significantly improved HER activity with a low overpotential of 80 mV at 10 mA cm−2, robust stability and good selectivity in alkaline solution compared with pure MoS2 and most MoS2‐based catalysts. In situ Raman and theoretical calculations prove that the oxophilic Tm in [Mo‐S‐Tm] unit sites significantly improves the migration and thermodynamic spontaneous dissociation of interfacial H2O molecules during HER by the Tm‐4f‐OH orbital overlap. Such [Tm‐S‐Mo] unit site allows the optimal G*H location of Tm SAs‐MoS2, which in turn reaches the apex of the theoretical HER volcano plot. This work is expected to open up new avenues for the design of novel alkaline HER catalysts and provide a valuable understanding of rare earth enhanced mechanisms. [ABSTRACT FROM AUTHOR]

As an efficient and environmental‐friendly strategy, electrocatalytic oxidation can realize biomass lignin valorization by cleaving its aryl ether bonds to produce value‐added chemicals. However, the complex and polymerized structure of lignin presents challenges in terms of reactant adsorption on the catalyst surface, which hinders further refinement. Herein, NiCo‐based metal‐organic frameworks (MOFs) are employed as the electrocatalyst to enhance the adsorption of reactant molecules through π‐π interaction. More importantly, lattice strain is introduced into the MOFs via curved ligand doping, which enables tuning of the d‐band center of metal active sites to align with the reaction intermediates, leading to stronger adsorption and higher electrocatalytic activity toward bond cleavage within lignin model compounds and native lignin. When 2′‐phenoxyacetophenone is utilized as the model compound, high yields of phenol (76.3%) and acetophenone (21.7%) are achieved, and the conversion rate of the reactants reaches 97%. Following pre‐oxidation of extracted poplar lignin, >10 kinds of phenolic compounds are received using the as‐designed MOFs electrocatalyst, providing ≈12.48% of the monomer, including guaiacol, vanillin, eugenol, etc., and p‐hydroxybenzoic acid dominates all the products. This work presents a promising and deliberately designed electrocatalyst for realizing lignin valorization, making significant strides for the sustainability of this biomass resource. [ABSTRACT FROM AUTHOR]

In response to the challenges of intermediate poisoning and the high cost of noble metal catalysts in the hydrogen evolution reaction (HER), we develop a Ru-doped SnO2 catalyst. This Ru–SnO2 catalyst has the characteristics of low Ru loading and a hollow structure, which endow it with good electrocatalytic activity and stability for the HER. [ABSTRACT FROM AUTHOR]

Pt‐based intermetallics are recognized as effective catalysts for oxygen reduction reaction (ORR) in fuel cells. However, the synthesis of intermetallics often requires prolonged annealing and the effect of different crystal structures on ORR still need to be investigated. Herein, L12‐Pt3Mn and L10‐PtMn intermetallics with Pt‐skin are rapidly synthesized through an emerging periodic carbothermal shock method to investigate their ORR‐activity difference. The formation of L12‐Pt3Mn and L10‐PtMn can be well‐controlled by the Pt/Mn feeding ratio, pulse cycles, and temperature. Electrocatalytic investigations show that L12‐Pt3Mn presents a more positive half‐wave potential (0.91 V vs RHE) and onset potential (1.02 V vs RHE) than those of L10‐PtMn. The mass activity and specific activity of L12‐Pt3Mn are respectively fourfold and threefold greater than those of L10‐PtMn. Theoretical calculations indicate that the L12‐Pt3Mn has a more substantial work function than L10‐PtMn, thereby conferring L12‐Pt3Mn with an increased electron density allocation for catalytic involvement. This electron confinement imparts L12‐Pt3Mn with a Pt d‐band center lower than that of L10‐PtMn, consequently attenuating the adsorption of strongly bonded *O intermediates during the rate‐determining step. This study not only employs a straightforward method for intermetallic preparation but also elucidates the discrepancies in ORR activity across intermetallics with distinct structures. [ABSTRACT FROM AUTHOR]

The active‐site density, intrinsic activity, and durability of Pd−based materials for oxygen reduction reaction (ORR) are critical to their application in industrial energy devices. This work constructs a series of carbon‐based rare‐earth (RE) oxides (Gd2O3, Sm2O3, Eu2O3, and CeO2) by using RE metal–organic frameworks to tune the ORR performance of the Pd sites through the Pd−RExOy interface interaction. Taking Pd−Gd2O3/C as a representative, it is identified that the strong coupling between Pd and Gd2O3 induces the formation of the Pd−O−Gd bridge, which triggers charge redistribution of Pd and Gd2O3. The screened Pd−Gd2O3/C exhibits impressive ORR performance with high onset potential (0.986 VRHE), half‐wave potential (0.877 VRHE), and excellent stability. Similar ORR results are also found for Pd−Sm2O3/C, Pd−Eu2O3/C, and Pd−CeO2/C catalysts. Theoretical analyses reveal that the coupling between Pd and Gd2O3 promotes electron transfer through the Pd−O−Gd bridge, which induces the antibonding‐orbital occupancy of Pd−*OH for the optimization of *OH adsorption in the rate‐determining step of ORR. The pH‐dependent microkinetic modeling shows that Pd−Gd2O3 is close to the theoretical optimal activity for ORR, outperforming Pt under the same conditions. By its ascendancy in ORR, the Pd−Gd2O3/C exhibits superior performance in Zn‐air battery as an air cathode, implying its excellent practicability. [ABSTRACT FROM AUTHOR]

The Co-based heterojunction is regarded as an efficient material for the oxygen evolution reaction (OER), but the synthesis is still time- and labor-consuming, and environmentally unfriendly. Herein, we propose a green and facile L -lysine-induced strategy for the successful synthesis of porous CoS/Co3O4 nanoframes (NFs). L -Lysine played a pivotal role in facilitating the formation of the stable Co(OH)2 nanosheet precursor, which was subsequently in situ converted into CoS/Co3O4 NFs through the sulfuration treatment. The resulting CoS/Co3O4 NFs showed a low overpotential of 304 mV at 10 mA cm−2 and remarkable long-range durability in 1.0 M KOH for the OER. The rechargeable Zn–air battery exhibited high charge–discharge cycling stability (>120 h) with CoS/Co3O4 NFs + Pt/C as an air cathode. Density functional theory calculations demonstrated that the charge density of the CoS/Co3O4 heterostructure can be redistributed by rebalancing the Fermi level after the contact between CoS and Co3O4, potentially modulating the pristine catalytic properties of single components. This work provides a facile and green synthesis strategy for developing efficient Co-based catalysts in sustainable energy conversion devices. [ABSTRACT FROM AUTHOR]

Rare‐earth (RE) elements have emerged as crucial promoters to regulate the electrocatalysis of transition metals (TM), but knowledge about the RE‐enhanced mechanism of TM in electrocatalysis is limited. Herein, an array‐like Ce‐CoP catalyst is constructed to explore the origin and distinction of the Ce‐induced enhanced mechanism of Co sites in both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Compared with individual CoP, the developed Ce‐CoP exhibits superior bifunctional electrocatalytic activity with the overpotentials of 81 and 240 mV at 10 mA cm−2, respectively for HER and OER, with excellent electrocatalytic stability. Theoretical calculations show that the unique 4f valence electron structure of Ce endows the Co sites with differentiated regulation in the HER and OER through f‐p‐d gradient orbital coupling. In the HER, the retained Ce‐4f state induces electron spin parallelism at the surrounding Co sites, promoting the adsorption of *H intermediates. While in the OER, the Ce‐4f band acts as sacrificing band to protect the Co sites from overoxidation through the Ce‐O‐Co chain with an optimized Co‐3d state, providing additional spin coupling with oxygen intermediates. These findings provide new insights into comprehending the RE‐enhanced mechanism of electrocatalysis and present valuable design guidelines for the development of efficient multi‐functional electrocatalysts. [ABSTRACT FROM AUTHOR]