Conventional Ni-based methanol oxidation reaction (MOR) electrocatalysts predominantly operate through a standalone nickel redox cycle, where slow surface reconstruction inherently limits their overall kinetic efficiency. Overcoming this fundamental limitation requires exploring complementary reaction pathways. Herein, we report an alternative MOR pathway unlocked via microenvironment engineering on ultrathin NiFeCr hydroxide (NiFeCr-OH) nanosheets. Cr induced electronic redistribution regulates interfacial OH- adsorption and promotes the formation of an *OH-enriched microenvironment. The *OH-enriched microenvironment enables an unconventional MOR pathway, driven by the interaction between nucleophilic methanol and electrophilic *OH. This parallel pathway synergizes with the Ni redox cycle, effectively bypassing the kinetic limitations of the slow Ni reconstruction process. Benefiting from this synergistic microenvironment and parallel reaction pathway, the NiFeCr-OH catalyst delivers a current density of 100 mA cm-2 at 1.44 V with high formate selectivity and long-term stability. These findings suggest that exploiting unconventional reaction pathways is an effective strategy for enhancing MOR efficiency, providing valuable insights into the design of practical and efficient electrocatalysts.
Developing organometallic complexes that combine strong nonlinear optical (NLO) responses with outstanding optical power limiting (OPL) performance is pivotal for laser protection and advanced optoelectronic devices. Yet, achieving substantial NLO amplification with precise and predictable tunability remains highly challenging. Here we present a topology- and size-programmable coordination-driven self-assembly that affords Pt(II) metallacycles (MPt-1–MPt-3) and reveals how metallacyclic topology and size influence third-order NLO responses. Photophysical studies indicate that formation of Pt(II) metallacycles modulates the electronic structure of the ligand (L-NI) while reinforcing framework rigidity and spin–orbit coupling (SOC), thereby affording prolonged triplet-state lifetimes (τT = 15.31–150.69 μs) and strengthened excited-state absorption (ESA). Consequently, MPt-1–MPt-3 display pronounced size-dependent NLO responses at 532 nm, outperforming both L-NI and C60. Notably, the [6+6] MPt-3 achieves an impressive effective nonlinear absorption coefficient (βeff = 1223.85 cm GW–1) and a large imaginary third-order susceptibility (Im χ(3) = 45.06 × 10–11 esu). This corresponds to a >190-fold enhancement over L-NI, placing MPt-3 among the highest-performing Pt(II) complexes reported under comparable conditions. This work demonstrates that coordination-driven self-assembly provides an effective platform for regulating excited-state dynamics in organometallic complexes and establishes a structure-guided design strategy for next-generation NLO materials
ZnO, with its polar wurtzite structure enabling favorable CO2 adsorption, emerges as a promising candidate for electrocatalytic CO2 reduction. However, its fully occupied 3d10 configuration inherently limits electron transfer and CO2 activation. Herein, we develop a synergistic dual-functional strategy by constructing ZnO-Ag heterostructures, where silver serves as a crystal "guide" to refine grain structure, and as an electronic "tractor" to induce local electron redistribution. The interplay of two functions creates a unique interfacial environment that synergistically promotes CO2 activation and conversion. The optimized Zn100Ag5 heterostructure demonstrates exceptional CO2 reduction performance, achieving a CO Faradaic efficiency of 93.8% with a high partial current density of 29.5 mA cm-2. Through combined experimental and theoretical analyses, we reveal that the built-in electric field (BIEF) arising from work function differences drives spontaneous electron transfer from Ag to Zn sites, significantly reducing the *COOH formation energy barrier and stabilizing *COOH adsorption. More critically, the interfacial charge equilibrium creates unique dual adsorption sites that simultaneously stabilize both C and O atoms of *COOH intermediates, as evidenced by pCOHP analysis showing stronger bonding interactions compared to single-component systems. In-situ Raman spectroscopy directly detects *COOH intermediates, experimentally confirming the enhanced adsorption and dual-atom stabilization mechanism. This work provides a rational design concept for developing efficient heterostructured electrocatalysts through precise electric field engineering and interfacial charge manipulation, offering a practical strategy for enhancing CO2 conversion via intermediate stabilization.
The development of efficient organic photocatalysts for sustainable hydrogen peroxide (H2O2) production provides a viable substitute for high-energy-consumption anthraquinone process. In this study, two pyrene-based conjugated microporous polymers (CMPs), Py-DBP and Py-DBB, were synthesized via Sonogashira-Hagihara coupling to systematically investigate the role of pyridinic nitrogen in modulating photocatalytic performance. Compared with benzene-linked analogue, pyridine-functionalized Py-DBP exhibits a significantly enhanced H2O2 production rate of 1560.5 μmol·g-1·h-1, 2.5 times higher than that of Py-DBB. Scaled-up reactor demonstrates consistent and stable H2O2 yield under natural sunlight. Mechanistic studies reveal that nitrogen incorporation modulates electronic structure, induces charge redistribution, and promotes separation and migration of photogenerated charge carriers. Enriched negative charge density at carbon sites adjacent to nitrogen atoms creates a favorable electrostatic environment for molecular oxygen adsorption and activation. Density functional theory calculations confirm that Py-DBP exhibits a lower Gibbs free energy for the formation of key *OOH intermediate, thereby improving both thermodynamic efficiency and kinetic favorability in two-step single-electron oxygen reduction pathway for H2O2 generation. These findings highlight heteroatom engineering as a powerful strategy for enhancing the photocatalytic performance of CMP-based materials.
Layered ferroelectric AgBiP2Se6 has recently emerged as a promising two-dimensional semiconductor for optoelectronic conversion, whereas its pressure-regulated structural evolution, electronic transport, and broadband photoresponse remain largely unexplored. Here, we combine in situ Raman spectroscopy, synchrotron X-ray diffraction, photocurrent measurements, AC impedance spectroscopy, and first-principles calculations to establish the pressure-structure-transport-photoresponse relationship in polycrystalline layered AgBiP2Se6. Upon compression, AgBiP2Se6 undergoes an isostructural transition at approximately 7.6 GPa, followed by a semiconductor-to-metal transition near 15.3 GPa and pressure-induced amorphization above ∼28.2 GPa. These structural and electronic reconstructions give rise to a pronounced broadband enhancement of the photoresponse. Under 365 nm illumination, the photocurrent density increases from 0.0068 to 7.69 mA cm-2, while the responsivity increases from 0.11 to 128.21 mA W-1, with both parameters exhibiting an approximately 1131-fold enhancement upon compression. Enhanced photoresponse is also observed in the visible and near-infrared spectral regions. AC impedance measurements and theoretical calculations reveal that the enhanced optoelectronic performance originates from pressure-enhanced electrical conductivity, improved carrier transport, and band-gap narrowing. This work identifies pressure-driven electronic reconstruction as an effective route for optimizing broadband photoresponse in layered AgBiP2Se6 and provides insight into pressure-regulated optoelectronic behavior in two-dimensional chalcogenide semiconductors.
Photocatalysis has emerged as a promising solar-driven technology for environmental remediation, renewable fuel production, and carbon-neutral chemical synthesis. Nevertheless, the practical efficiency of many photocatalytic systems remains limited by the redox-potential loss associated with conventional type-II heterojunctions, where improved charge separation is often achieved at the expense of photocatalytic driving force. The S-scheme heterojunction has recently gained considerable attention as an alternative charge-transfer model that overcomes this limitation. Through the formation of a built-in interfacial electric field, S-scheme systems selectively recombine low-energy charge carriers while retaining highly reducing electrons and highly oxidizing holes, thereby maximizing photocatalytic redox capability. Perovskite materials are attractive building blocks for S-scheme photocatalysts because their composition and structure can be readily tailored to regulate band structures, Fermi-level positions, defect concentrations, dielectric properties, and piezoelectric responses. These unique characteristics provide extensive opportunities for optimizing interfacial charge transfer and photocatalytic performance. This review critically evaluates recent advances in perovskite-based S-scheme heterojunctions, focusing on the fundamental mechanisms governing charge separation, including Fermi-level equilibration, band bending, interfacial electric field formation, and the influence of Fermi-level pinning on long-term photocatalytic operation. The review further examines rational design approaches, including compositional and defect engineering, interface modulation, hierarchical two-dimensional and core-shell architectures, dual S-scheme systems, cocatalyst integration, and emerging machine-learning-assisted materials discovery. Mechanistic insights into key photocatalytic applications (including pollutant degradation, reactive oxygen species generation, hydrogen evolution, hydrogen peroxide production, CO2 photoreduction, and bicarbonate-to-formate conversion) are discussed, with emphasis on the combined use of in situ DRIFTS and DFT calculations to elucidate reaction pathways and product selectivity. The role of advanced characterization techniques, such as ISIXPS, KPFM, transient absorption spectroscopy, EPR, and operando spectroscopies, in validating S-scheme charge-transfer mechanisms is also highlighted. Finally, major challenges, including the stability limitations of halide perovskites, interfacial evolution during operation, activity-stability trade-offs, and the lack of standardized benchmarking protocols, are critically assessed. Future progress will depend on the integration of advanced operando characterization, data-driven materials discovery, environmentally benign perovskite design, and scalable reactor technologies, paving the way for the practical implementation of perovskite-based S-scheme photocatalysts in sustainable energy and environmental applications.
Piezoelectric catalysis is an advanced oxidation technology based on the electromechanical coupling effect, which directly converts mechanical energy in the environment into chemical energy through piezoelectric materials to drive efficient oxidation reactions for water purification. The core mechanism of this technology originates from the piezoelectric polarization field induced by mechanical stress, which can effectively regulate the band structure of materials, promote the separation and migration of charge carriers, and thereby stimulate the generation of reactive oxygen species to achieve efficient degradation of organic pollutants and inactivation of microorganisms. This review summarizes the basic principles of piezoelectric catalysis, focuses on the latest progress in piezoelectric catalysis-driven types, and then sorts out the design ideas of piezoelectric catalytic materials from three major systems: inorganic, organic polymers, and emerging two-dimensional materials. It systematically summarizes the performance optimization strategies of morphology control, defect engineering, heterostructure construction, and noble metal deposition. Finally, it reviews the application exploration in water pollution control, disinfection and sterilization, and heavy metal removal, and proposes current bottlenecks and future development prospects.
As key components of lithium-ion batteries (LIBs), anode materials can determine the capacity, stability, and safety of LIBs. Transition metal oxides have been regarded as promising LIB anodes due to their low cost, natural abundance, and substantial theoretical capacity. Nevertheless, the large-scale use of metal oxides is hampered by their intrinsic demerits, including low conductivity and large volume fluctuation. Several strategies have been proposed to address these limitations, such as morphological/structural design, heterostructuring, and defect engineering. It’s feasible to integrate the above strategies by using suitable self-sacrificial templates. Owing to their multiformity, porosity, and large surface area, metal-organic frameworks (MOFs) remain suitable templates for metal oxide fabrication. Herein, this work develops a series of oxygen-deficient (FeCoNi)3O4 using different MOFs (terephthalic acid, 1,3,5-benzenetricarboxylic acid, and pyromellitic acid) as self-sacrificial templates (denoted as FCNO-PTA, FCNO-BTC, and FCNO-PTC, respectively). Both experimental and theoretical studies reveal that abundant oxygen vacancies can create local built-in electric fields. This not only provides additional lithium adsorption sites but also facilitates the formation of a robust solid electrolyte interface (SEI), thereby mitigating the lattice strain upon lithiation/delithiation and enhancing overall performance. Remarkably, FCNO-PTC demonstrates the optimal reversible capacities (1176 mAh g–1 at 0.2 A g–1 after 150 cycles; 725 mAh g–1 at 1 A g–1 after 350 cycles) due to its higher oxygen vacancy content. This work provides new insights into the optimisation of metal oxides at an atomic scale.
Enhancing the migration of photogenerated charges in semiconductor catalysts is an important way to enhance hydrogen (H2) production. We fabricated ZnIn2S4-CuNiP (Z-CuNiP) heterostructure by a simple ultrasonic blending method. These composites can be thought of as cheaper substitutes for expensive metal cocatalysts such as platinum or palladium. The incorporation of CuNiP was found to be highly efficacious in increasing the photocatalytic performance of ZnIn2S4 (ZIS) in visible light of relatively low intensity to reach a H2 production rate of 1.06 mmol·g-1·h-1. This is roughly four times that of pure ZIS. A key characteristic is the occurrence of a wide and close contact between ZIS and CuNiP that allows separation of photoinduced electron-hole pairs. Due to this, the efficiency of photocatalytic water splitting with respect to ZIS of the designed heterostructure increases significantly.
Rationally regulating the dynamic reconstruction of metal-organic frameworks (MOFs) under oxygen evolution reaction (OER) conditions is essential for developing highly active and durable catalysts, yet the role of rare-earth dopants in regulating the reconstruction mechanism remains poorly understood. Herein, we report a Cerium-doped NiFc-MOF catalyst on nickel foam (NiFcCe-MOF) to elucidate the Ce-steered reconstruction pathway during the OER process. Combined ex situ and in situ characterizations reveal that Ce incorporation drives the metal active centers toward high-spin electronic configurations, increasing their susceptibility to OH- attack and thereby promoting ligand dissociation to accelerate reconstruction kinetics. Simultaneously, the presence of Ce also promotes dynamic rearrangement of the local coordination environment in NiFcCe-MOF, steering the reconstruction pathway toward a more disordered γ-NiFeCeOOH active phase. Density functional theory (DFT) calculations further reveal that the reconstructed NiFeCeOOH phase exhibits a d-band center shifted away from the Fermi level, which balances the adsorption-desorption behavior of oxygenated intermediates and ultimately lowers the barrier of the potential-determining OH* → O* step. As a result, NiFeCeOOH achieves 100 mA cm-2 at an overpotential of only 231 mV, together with long-term durability exceeding 1500 h. This work underscores rare-earth-mediated control over reconstruction pathways as an effective strategy for rationally designing reconstruction-derived high-performance OER catalysts.
Selective ethanol dehydrogenation to acetaldehyde is a key step in biomass upgrading, yet achieving both high selectivity and activity remains challenging due to competing reaction pathways. Precise catalyst design is therefore essential. Herein, defective UiO-66 was synthesized via formic acid modulation and employed to precisely anchor Cu species, enabling controlled formation of single-atom and multi-atom Cu sites. At low Cu loading, atomically dispersed Cu sites stabilized at defect positions exhibit nearly complete selectivity toward acetaldehyde (≈100%) and an exceptional intrinsic activity of up to 7045 mmol g Cu-1 h-1. In contrast, higher Cu loading leads to the formation of Cu ensembles, which promote secondary reactions, including acetaldehyde coupling to acetone and C4 products, resulting in decreased selectivity. Density functional theory calculations reveal that single Cu sites lower the activation barrier for C-H bond cleavage and weaken product binding, favoring acetaldehyde formation. In contrast, multi-Cu sites induce stronger adsorption and facilitate further transformations. These findings demonstrate that defect engineering in metal-organic frameworks (MOFs) enables precise control over metal nuclearity, providing a rational strategy for designing highly selective and efficient single-atom catalysts.
A series of tetraphenylethylene (TPE)-functionalized chiral Au(I) N-heterocyclic carbene (NHC) complexes (R/S-1 to R/S-4) were designed and synthesized. A novel solvent-cooperative chiral transfer strategy was established to precisely manipulate the helical chirality of TPE moieties in crystals. Efficient intramolecular chiral transfer from chiral NHC to TPE was achieved in dilute solutions. Meanwhile, these complexes exhibited aggregation-induced circularly polarized luminescence (CPL) in THF/H2O mixtures. By varying crystallization solvents, the identical chiral NHC could induce opposite P- or M-helical conformations of TPE, in which achiral solvent molecules acted as chiral transfer mediators and stabilized the chiral conformations of TPE through weak intermolecular interactions with host molecules. Impressively, the dichloromethane co-crystals of R/S-4 containing four homochiral TPE units showed outstanding CPL performance with a |glum| value of 2.1 × 10−2 and a photoluminescence quantum yield exceeding 69%, benefiting from the effective locking of TPE chirality via C–H⋯F interactions with PF6− anions. This work reveals the synergistic mechanism of solvents in solid-state chiral transfer and provides a concise and efficient approach for constructing high-performance CPL crystalline materials.
