Cr doping activates Ni(OH)2 surface chemistry for complete PET conversion, where Cr-Ni charge transfer enriches Ni3+ and promotes OH-/EG co-adsorption.

Electrocatalytic hydrogen production is pivotal for advancing the transition to green energy. However, its widespread application is hindered by the limited efficiency of electrocatalysts and the sluggish kinetics of the anodic oxygen evolution reaction (OER). Developing high-performance, durable, and cost-effective electrocatalysts, coupled with the substitution of OER with thermodynamically more favorable oxidation reactions, represents a promising strategy to address these challenges. Herein, we successfully fabricated a novel transition metal-based high-entropy hydroxyl carbonate (HE-HC) catalyst. Comprehensive experimental and computational characterizations demonstrate that the resulting catalyst exhibits superior catalytic activity for the benzyl alcohol oxidation reaction (BOR), achieving high selectivity and Faradaic efficiency (FE) toward the value-added product, benzoic acid. This work not only presents a novel metal-organic framework (MOF)-derived high-entropy catalyst for efficient alcohol oxidation co-electrolysis but also provides fundamental insights into the design principles of multi-metallic catalysts for coupled energy conversion and chemical synthesis processes.

The heterogeneous Mn-NiFe(Ox)/NC catalyst, endowed with abundant active sites, facilitates a notably low onset potential for the nitrate reduction reaction. In situ Raman spectra provide direct evidence for the better performance of Mn-NiFe(Ox)/NC and key reaction intermediates.

Lignin represents the most abundant non-fossil aromatic carbon resource on Earth, and its efficient valorization is crucial for the full utilization of biomass and sustainable development. However, its complex three-dimensional structure and robust linkages pose significant challenges for conventional depolymerization methods, which often suffer from harsh conditions and poor selectivity. Electrocatalytic oxidation has emerged as a promising green strategy for the selective cleavage of lignin under mild conditions, offering a sustainable pathway to high-value aromatic chemicals. This review systematically summarizes recent advances in transition metal-based electrocatalysts for the electro-oxidative depolymerization of lignin (eLDP). It highlights and compares the design strategies and performance of noble-metal-based catalysts (e.g., Pt, Au, Ir) and earth-abundant non-noble-metal-based systems (e.g., Pb, Ni, Co). Rational catalyst design, through modulating electronic structures, coordination environments, and surface properties, can effectively promote the generation of reactive oxygen species (ROS) and facilitate the selective cleavage of key linkages (e.g., β-O-4 bonds) while suppressing the competing oxygen evolution reaction. This leads to improved yields and selectivity of valuable aromatic monomers such as phenols, aldehydes, and acids. Despite significant progress, major challenges remain in designing catalysts with simultaneously high activity, selectivity, and long-term stability, and in transitioning from model compounds to real lignin feedstocks. Future research should focus on elucidating reaction mechanisms via in situ characterization and theoretical calculations, and further optimizing catalysts through strategies like multi-metal synergy and defect engineering.

Electrochemical methanol upgrading (EMU) represents a sustainable and energy-efficient pathway for producing value-added formate, underscoring the urgent demand for EMU electrocatalysts with enhanced activity and stability. In this work, a multimetal Prussian blue analogue (PBA)/copper hydroxide nanoarray catalyst supported on copper foam (5-PBA/CH/CF) was synthesized via an anodization-self-sacrificial template approach. This strategy synergistically optimizes both active site density and intrinsic activity for efficient EMU to formate. The catalyst leverages multimetal synergy and catalytic ensemble effects to tailor electronic structures. The hierarchical PBA architecture not only exposes abundant high-valence active sites but also provides plentiful reactive sites for enhanced preoxidation, thereby enabling further enrichment of active species. This dual effect concurrently boosts catalytic activity and operational stability. Capitalizing on these structural merits, the 5-PBA/CH/CF catalyst delivers exceptional EMU performance, requiring only 1.355 V vs RHE to achieve 50 mA cm-2 current density while maintaining near 100% Faradaic efficiency (FE) across a broad potential window (1.3-1.5 V vs RHE). Moreover, stability testing over 96 h revealed significant current density enhancement coupled with excellent FE retention. This work establishes a new paradigm for designing highly efficient and ultrastable electrocatalysts for methanol valorization, and provides an efficient and durable catalyst for green electrosynthesis of value-added formate.

A ternary FeCoCuOx porous hierarchitecture catalyst protected by nitrogen-doped carbon was fabricated, which displays multimetal synergy and microstructural benefits for facile hydrazine electro-oxidation reaction.

A bismuth-incorporated NiFe hydroxide ultrathin nanoarray catalyst was synthesized, which exhibits enriched Ni3+ species and a lattice-disordered polycrystalline/amorphous structure for efficient and durable electrochemical methanol upgrading.

Exploring advanced electrocatalyst for the oxygen evolution reaction (OER) is of great importance in pursuing efficient and sustainable hydrogen production via electrolytic water splitting. Considering the structure-activity-stability relationship for designing advanced OER catalysts, two-dimensional (2D) porous catalyst with single crystallinity is deemed to be an ideal platform which could simultaneously endow enriched active sites, facile mass and charge transport ability as well as robust structural stability. Herein, we proposed a facile 2D confined topotactic phase transformation approach, which realizes the fabrication of highly porous single-crystalline Co3O4 nanosheets with in-situ surface modification of amorphous Co-Pi active species. Benefitted from the highly exposed undercoordinated cobalt sites, facilitated mass transport and facile 2D charge transfer pathway, the Co-Pi/Co3O4 hybrid porous nanosheets display enhanced OER activity with obvious pre-oxidation-induced activation. In addition, the operational stability was significantly improved owing to the strengthened structural stability which effectively buffers the internal strains and avoids the structural collapse during the electrochemical process. This work proposed a facile and mild method for the synthesis of amorphous/single-crystalline hybrid porous materials, and the achievement of synergistic modulation of active site density and charge transfer ability via targeted microstructural construction will shed light on catalyst design in the future.

Electrochemical CO2 reduction reaction (CO2RR) to formate presents a technoeconomic route for CO2 utilization under mild conditions, yet practical implementation is constrained by the high energy consumption (> 90% of total input) of the anodic oxygen evolution reaction (OER). Replacement of OER by partial methanol oxidation reaction (MOR) could lead to simultaneous formate production at both electrodes and remarkably reduce the overall energy consumption. Herein, we designed a two-electrode system featuring a nickel foam-supported crystalline/amorphous bismuth-bismuth nickel oxide composite cathode (Bi-BiNiOx/NF) and a beta-Ni(OH)(2) anode, achieving excellent formate production behavior. The crystalline/amorphous Bi-BiNiOx/NF cathode delivers exceptional CO2RR performance, achieving 98.9% formate Faradaic efficiency (FEformate) at-0.90 V vs. reversible hydrogen electrode (RHE) and maintaining > 90.7% FEformate over 72 h continuous operation-attributed to its Bi-Ni bimetallic synergy and crystalline/amorphous heterostructure that enhance active site exposure and reaction kinetics. The integrated CO2RR||MOR system operates stably for 90 h at 2.2 V and 10 mAcm(-2), sustaining > 90% FEformate at both electrodes with a cell voltage (1.760 V) significantly lower than conventional CO2RR||OER systems (1.953 V). This work demonstrates efficient concurrent formate electrosynthesis and establishes an energy-efficient paradigm for electrocatalytic CO2 valorization through synergistic catalyst design and reaction pathway integration.

The electrochemical glycerol oxidation reaction (GOR) offers a promising alternative to the anodic oxygen evolution reaction in water electrolysis, enabling simultaneous energy-saving hydrogen production and sustainable synthesis of value-added formate. Current advances reveal that high-valence transition metal species critically enhance C-C cleavage during glycerol electro-oxidation, with targeted enrichment of these active sites-via local structure design or in situ reconstruction-proving highly effective. Herein, we engineered a high-entropy FeCrCoNiCu layered hydroxide (HE-LH) catalyst featuring a hybrid quasi-single-crystalline (QSC)/amorphous nanostructure. This design synergistically integrates locally engineered and in situ enriched high-valence active sites for efficient glycerol-to-formate conversion. The high-entropy composition induces a distinctive catalytic ensemble effect, elevating intrinsic GOR activity, while the QSC/amorphous heterostructure maximizes the density of electrochemically (re)active sites. Leveraging this dual optimization, HE-LH achieves an exceptional formate faradaic efficiency of 92.9% and maintains >83% efficiency over five consecutive cycles. This work pioneers a co-design strategy for electrocatalysts by concurrently optimizing active site density and intrinsic activity, establishing high-entropy layered hydroxides as durable platforms for electrochemical biomass upgrading.

The development of efficient catalysts for nitrate reduction to ammonia is crucial for sustainable nitrogen cycle management. In this study, we introduce an amorphous multimetal borides (CoFeNiB) catalyst that demonstrates exceptional performance in the electrochemical reduction of nitrate to ammonia. X-ray photoelectron spectroscopy (XPS) and in-situ Raman spectroscopy reveal that the catalyst exhibits a unique surface reconstruction during the reaction, leading to the formation of CoOOH, where Co3+ ions can serve as active sites, significantly enhancing the adsorption of nitrate ions and atomic hydrogen, thereby promoting the reduction reaction. Specially, besides the activity enhancement of CoFeNiB compared with CoFeB and CoB, the stability of it can be markedly improved by the synergistic effect of Ni and Fe in the catalyst. Consequently, the CoFeNiB catalyst achieves a stable Faradaic efficiency above 90 % across a broad voltage range of 0 ∼ -0.6 V vs reversible hydrogen electrode (RHE) and an ammonia yield peaked of 3961.4 mmol gcat-1 h-1 at -0.6 V vs RHE. The CoFeNiB catalyst offers a promising avenue for the efficient and stable synthesis of ammonia from nitrate, addressing key challenges in environmental sustainability and nitrogen management.

Hydrazine-assisted water electrolysis pledges low-input/input-free hydrogen production coupled with hydrazine sewage treatment. Herein, CuCo bimetallic nanoparticles (NPs) were prepared and spatial-confined in the nitrogen-doped carbon (NC) flowers by direct pyrolysis of Cu incorporated zeolitic imidazolate framework precursors (CuCo@NC/CC). The unique nanoflower structure assembled by nanosheets with surface folds can not only expose abundant marginal active sites with lower coordination numbers but also shorten the diffusion pathways, acting as a micro-electrolyte storage reservoir to facilitate rapid ion transfer. Meanwhile, the interaction between Cu and Co can effectively optimize the electronic structure of catalyst to enhance the electrical conductivity and charge transport ability with the synergistic effect of the strong interfacial coupling between metal NPs and NC matrix. Notably, the spatial confinement of carbon sheet effectively prevents the agglomeration of CuCo NPs during the repetitive redox reactions, thereby maintaining the undamped catalytic performance and ensuring impressive stability. Consequently, CuCo@NC/CC displays prominent activity on hydrazine oxidation with low potential of -77 mV to achieve 10 mA cm- 2. Furthermore, a waste battery-powered hydrogen evolution reaction (HER)||hydrazine oxidation reaction (HzOR) system achieves a high hydrogen production rate of 0.12 mmol min- 1 cm- 2. Importantly, this HER||HzOR unit can be further powered by a homemade zinc-hydrazine battery based on CuCo@NC/CC with a high energy efficiency of 96.4 %, yielding lowinput/input-free green hydrogen production day-and-night.

An innovative hollow sandwich system, featuring engineered crystalline-amorphous interfaces, enables efficient conversion of PET waste into valuable chemicals, achieving complete recycling with strong commercial viability.

We report a phosphate-incorporated Cu(OH)2 nanoarray catalyst featuring lattice distortion and a quasi-single-crystalline structure. This unique design enriches local active sites and facilitates pre-oxidation, achieving 99.9% faradaic efficiency for electrochemical methanol-to-formate conversion with 120-hour stability.

In this work, a grain-boundary-engineered porous CuO/Co3O4 heterostructure was fabricated as a dynamic pre-catalyst, where tailored grain boundaries and nanopores facilitate pre-oxidation to activate high-valence species for robust oxygen evolution.

The electrochemical reduction of nitrate to ammonia is a promising approach for nitrogen resource recovery and environmental remediation. In this study, we investigate the catalytic performance of cobalt phosphide incorporated in the carbon skeleton (CoP/C) as an efficient catalyst for this reaction. The strong interaction between Co and P constructs a unique electronic structure for the catalyst, enabling its catalytic performance and stability to be significantly superior to that of metal Co, cobalt phosphate (Co(PO3)2), or cobalt oxide (Co3O4). In situ Raman spectroscopy and online differential electrochemical mass spectrometry were employed to identify the intermediate products formed during the catalytic process, providing valuable insights into the reaction mechanism. Furthermore, first-principles calculations highlighted the significant role of Co-P active species in promoting the selectivity of the catalytic process. Consequently, the CoP/C catalyst achieves a peak Faradaic efficiency of 97.5% at -0.2 V versus the reversible hydrogen electrode (RHE) and a peak ammonia yield of 4.2 mol gcat-1 h-1 at -0.6 V versus RHE. Our findings suggest that optimizing the Co-P interaction within the CoP/C catalyst could lead to improved efficiency in the electrochemical reduction of nitrate, paving the way for sustainable ammonia synthesis.

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A ternary iron–cobalt–nickel hydroxide nanoarray catalyst was fabricated, which achieves enhanced performance towards electro-oxidative depolymerization of lignin models to produce benzoic acid and phenol.

Efficient coupling of economically favorable electro-oxidation reactions with the hydrogen evolution reaction (HER) has been considered as a promising way to realize synergistic production of hydrogen and value-added chemicals.