Topotactic Transformation Research Articles

Development of inorganic–organic CdSe(en)0.5via microwave-assisted method and topotactic transformation into porous CdSe nanosheet photoanode for photoelectrochemical hydrogen production

In this study, inorganic–organic hybrid CdSe(en)0.5 nanosheet (NS) was developed on Cd foil via the microwave-assisted (MW) method with different MW irradiation cycles. Furthermore, the photoelectrochemical (PEC) performance of the mother material was improved through a second hydrothermal method with different time variations (3, 6, and 12 h at 160 °C). After the second hydrothermal, organic moieties were removed, and a porous photoanode was obtained. The optimized CdSe-6H photoanode showed a photocurrent density of 7.4 mA cm−2 (0 V vs Ag/AgCl) with 272 μmol cm−2/3h hydrogen gas evolution under one sun illumination. The enhanced PEC performance was attributed to the topotactic transformation, improved light absorbance, enhanced charge separation, and improved surface area. This work offers a rational approach for building inorganic–organic electrodes through the MW method and porous photoanode for PEC hydrogen production.

Facile synthesis of multifunctional zeolitic imidazolate framework-8 coatings on diverse bare substrates using a one-step strategy

Rational growth of metal–organic frameworks (MOFs) with controllable morphology and surface properties has been challenging. In this study, facile synthesis of zeolitic imidazolate framework-8 (ZIF-8) in solutions as well as direct in-situ growth of ZIF-8 on various untreated substrates was studied systematically. ZIF crystals with controllable morphology and size were prepared by simply adjusting the ethanol content in the co-solvent system, achieving a rational synthesis of ZIFs in controlled environments. More importantly, co-solvent content was proved to be crucial in the inter-dimensional topotactic phase transformation from a 2-dimensional ZIF-L to a three-dimensional ZIF-8. Then, the facile in-situ crystallization of ZIF-8 on a variety of untreated substrates was studied. With the use of co-solvents, ZIF-8 crystals were formed uniformly and continuously on all substrates regardless of the nature of the support material, including organic supports such as nylon membranes, 3D printed meshes, melamine sponges, mask filter layers, fabric, metallic support stainless-steel meshes, and ceramic pellet. This facile coating strategy provided controllable crystal coating morphology, size, and coating density, without surface modification/pre-treatment steps which are commonly used in the synthesis of high-quality ZIF coatings/membranes. The ZIF-8 coated substrates prepared in a co-solvent system displayed superior performance in some environmental remediation and biomedical applications. For example, the ZIF-8-coated nylon membrane achieved an impressive 96 ∼ 98 % small oil droplet removal from emulsions while maintaining a high water flux of ∼ 1200 L m−2h−1 bar−1. The superhydrophobic ZIF-8-coated melamine sponges were effective for fast oil adsorption. Last but not least, the ZIF-8-coated masks demonstrated greatly improved antibacterial activities. Overall, the co-solvent synthesis method reported in this work has enabled a one-step universal strategy for the direct growth of zeolitic imidazolate framework coating on diverse bare substrates with controlled surface properties and thus showed significant commercial potential in environmental and biological applications.

Hydrogen-Induced Topotactic Phase Transformations of Cobaltite Thin Films.

Manipulating physical properties through ion migration in complex oxide thin films is an emerging research direction to achieve tunable materials for advanced applications. While the reduction of complex oxides has been widely reported, few reports exist on the modulation of physical properties through a direct hydrogenation process. Here, we report an unusual mechanism for hydrogen-induced topotactic phase transitions in perovskite La0.7Sr0.3CoO3 thin films. Hydrogenation is performed upon annealing in a pure hydrogen gas environment, offering a direct understanding of the role that hydrogen plays at the atomic scale in these transitions. Topotactic phase transformations from the perovskite (P) to hydrogenated-brownmillerite (H-BM) phase can be induced at temperatures as low as 220 °C, while at higher hydrogenation temperatures (320-400 °C), the progression toward more reduced phases is hindered. Density functional theory calculations suggest that hydroxyl bonds are formed with the introduction of hydrogen ions, which lower the formation energy of oxygen vacancies of the neighboring oxygen, enabling the transition from the P to H-BM phase at low temperatures. Furthermore, the impact on the magnetic and electronic properties of the hydrogenation temperature is investigated. Our research provides a potential pathway for utilizing hydrogen as a basis for low-temperature modulation of complex oxide thin films, with potential applications in neuromorphic computing.

Evolution of Correlated Morphological and Structural Disorder in Boehmite‐Derived Alumina with Progressive Calcination

AbstractThis study explores the morphological and structural transformation of boehmite (AlOOH) into transition aluminas during calcination, a pathway crucial for diverse industrial applications. The primary focus is on the topotactic transformation of boehmite into γ‐Al2O3 and its subsequent transitions into higher temperature polymorphs, culminating in α‐Al2O3. Utilizing a combination of in situ X‐ray diffraction, in situ and ex situ transmission electron microscopy, 27Al solid‐state nuclear magnetic resonance, thermogravimetric analysis, nitrogen physisorption, and mercury porosimetry, this work provides insights into the morphological and structural reordering during the calcination process. Furthermore, the study highlights the significant impact of thermal processing on the morphological evolution of boehmite and transition aluminas, characterized by changes in pore structure sizes and shapes. These findings offer valuable insights for optimizing the properties of alumina‐based materials for specific applications.

Unraveling nano-scale effects of topotactic reduction in LaNiO2 crystals

Infinite-layer nickelates stand as a promising frontier in the exploration of unconventional superconductivity. Their synthesis through topotactic oxygen reduction from the parent perovskite phase remains a complex and elusive process. This study delves into the nano-scale effects of the topotactic lattice transformation within LaNiO2 crystals. Leveraging high-resolution scanning transmission electron microscopy and spectroscopy, our investigations uncover a panorama of structural alterations, including grain boundaries and coherent twin boundaries, triggered by reduction-induced transformations. In addition, our analyses unveil the formation of an oxygen-rich disordered transition phase encircling impurities and pervading crystalline domains and the internal strain is accommodated by grain boundary formation. By unraveling these nano-scale effects, our findings provide insights into the microscopic intricacies of the topotactic reduction process elucidating the transition from the perovskite to the infinite-layer phase within nickelate bulk crystals.

Two-dimensional confined topotactic transformation to produce Co-Pi/Co3O4 hybrid porous nanosheets for promoted water oxidation

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.

Investigating the crystallite morphologies and aggregation in boehmite powders: a combined analysis of two- and three-dimensional electron microscopy with x-ray diffraction

Boehmite (AlOOH) is considered as an important precursor to γ-Al2O3 which when calcinated undergoes topotactic transformation to form the latter. Alumina has extensive applications in fields such as catalysis, abrasives, cosmetics among others. Boehmite falls under the category of hierarchical structures whose structural and textural properties are a result of its compositional and porous hierarchy. Although research has been carried out exquisitely to understand the complete representation of its structure, a true morphological model is an important key to understand and fully explain its transport properties during catalytic processes. 3D electron microscopy helps us to dive deeper into the different hierarchical entities of boehmite, bridging the gaps between the models and assumptions made using some more traditional characterization techniques. We present here deeper insight into the structural and morphological parameters of different commercial boehmites using 3D-TEM. Through the extraction of quantitative descriptors pertaining to hierarchical entities and subsequent comparison with bulk analyses, precise and comprehensive information regarding these microstructures can be obtained. The results of our study indicate that boehmite grades, which appear to be identical in terms of their grades, display discrepancies in the uniformity of particle sizes. Moreover, diverse platelet interactions result in varying types of pores in these grades. Furthermore, it has been observed that the interfacial interactions among various crystallographic planes exhibit variations across different specimens, thereby contributing to the distinctive compositions within the aggregates. The variation in aggregates of different boehmite grades is also reflected in the combination of four distinct quantified morphologies.

Performance activation mechanism of aluminum-based layered double hydroxides adsorbents for recovering Li+ by pH modulating

Aluminum-based adsorbents, simply prepared by eluting the lithium-aluminum layered double hydroxide precursors with deionized water, is the only industrialized adsorbents for selectively separating Li+ from saline brines. Taking the roles of lattice and surface Li+ active sites on its performances into consideration, influence of ending pH modulating on prominently improving the adsorbing capacity and stability of aluminum-based adsorbents prepared by precipitation method is initially investigated. As experimentally evidenced that, the maximum desorption amount of Li+ at the eluting stage should be controlled to around 20 mg/g Li+ rather than thoroughly removed to effectively avoid the topotactic solid-phase transformation from adsorbent to α-Al(OH)3. As-prepared adsorbents not only has high adsorption capacity up to 8.4 mg/g in 400 ppm LiCl solution, but also owns unique self-healing ability, thus promising the excellent cycling stability. It is firstly proposed that the formation of the layer-structured precursor by precipitation method is well in accordance with the three-step formation mechanism and pH modulating mainly contributes to the anions exchange between solution Cl- and interlayer OH–. This study experimentally proves the importance of pH adjusting for preparing high performance lithium adsorbents by precipitation method, which is very significant and important for effectively extracting lithium resources from the complicated multi-component liquid minerals.

Template-Assisted Visible Light-Induced [2 + 2] Photodimerization in a Pseudopolymorphic Binary Solid: Topotactic Transformation vs Photoinduced Crystal Melting

Template-Assisted Visible Light-Induced [2 + 2] Photodimerization in a Pseudopolymorphic Binary Solid: Topotactic Transformation vs Photoinduced Crystal Melting

Reconstructable Carbon Monolayer-MoS2 Intercalated Heterostructure Enabled by Atomic Layers-Confined Topotactic Transformation for Ultrafast Lithium Storage.

The intercalation structure of two-dimensional materials with expanded interlayer distance can facilitate mass transport, which is promising in fast-charging lithium-ion batteries (LIBs). However, the designed intercalation structures will be pulverized and destroyed under tough working conditions, causing overall performance deterioration of the batteries. Here, we present that an intercalated heterostructure made of the typical layered material of MoS2 intercalated by N-doped graphene-like carbon monolayer (MoS2/g-CM) through a polymer intercalation strategy exhibits a unique behavior of reversible reconstructability as an LIB anode during cycling. A mechanism of "carbon monolayers-confined topotactic transformation" is proposed, which is evidenced by substantial in/ex situ characterizations. The intercalated heterostructure of MoS2/g-CM featuring a reconstructable property and efficient interlayer electron/ion transport exhibits an unprecedented rate capability up to 50 A g-1 and outstanding long cyclability. Moreover, the proposed strategy based on g-CM intercalation has been extended to the MoSe2 system, also realizing reconstructability of the intercalated heterostructure and improved LIB performance, demonstrating its versatility and great potential in applications.

Mechanisms of Hysteresis and Reversibility across the Voltage-Driven Perovskite-Brownmillerite Transformation in Electrolyte-Gated Ultrathin La0.5Sr0.5CoO3-δ.

Perovskite cobaltites have emerged as archetypes for electrochemical control of materials properties in electrolyte-gate devices. Voltage-driven redox cycling can be performed between fully oxygenated perovskite and oxygen-vacancy-ordered brownmillerite phases, enabling exceptional modulation of the crystal structure, electronic transport, thermal transport, magnetism, and optical properties. The vast majority of studies, however, have focused heavily on the perovskite and brownmillerite end points. In contrast, here we focus on hysteresis and reversibility across the entire perovskite ↔ brownmillerite topotactic transformation, combining gate-voltage hysteresis loops, minor hysteresis loops, quantitative operando synchrotron X-ray diffraction, and temperature-dependent (magneto)transport, on ion-gel-gated ultrathin (10-unit-cell) epitaxial La0.5Sr0.5CoO3-δ films. Gate-voltage hysteresis loops combined with operando diffraction reveal a wealth of new mechanistic findings, including asymmetric redox kinetics due to differing oxygen diffusivities in the two phases, nonmonotonic transformation rates due to the first-order nature of the transformation, and limits on reversibility due to first-cycle structural degradation. Minor loops additionally enable the first rational design of an optimal gate-voltage cycle. Combining this knowledge, we demonstrate state-of-the-art nonvolatile cycling of electronic and magnetic properties, encompassing >105 transport ON/OFF ratios at room temperature, and reversible metal-insulator-metal and ferromagnet-nonferromagnet-ferromagnet cycling, all at 10-unit-cell thickness with high room-temperature stability. This paves the way for future work to establish the ultimate cycling frequency and endurance of such devices.

In Situ Reconstruction to Surface Sulfide Adsorbed Metal Scaffold for Enhanced Electrocatalytic Hydrogen Evolution Activity

AbstractTransition‐metal‐based compounds have been intensively explored as efficient electrocatalysts for hydrogen evolution reaction (HER). Feasible reconstruction to the real active sites, which is yet to be identified, endows the promotion of HER activity. Here, it is reported that the incoming S coordinates and anion vacancies prompt the structural reconstruction of S‐doped Co3O4 on carbon cloth (S‐Co3O4/CC) during HER. A list of in situ studies reveals that the real active sites for HER are the “metallic surface‐adparticles” system embracing metallic Co scaffold and the dilute coverage of S coordinated Coδ+. Reaction mechanism exploration illustrates that interfacial perimeters between the coverage of Co3S4 moieties and metallic Co considerably facilitate the adsorption of H*, improve the kinetics of water dissociation, and consequently promote HER activity. The exemplified sulfide‐mediated topotactic transformation strategy is extended to the preparation of S, Fe codoped Ni(OH)2 (S‐NiFe/CC) as a bifunctional electrocatalyst. The assembled anion exchange membrane water electrolyzer achieves a current density of 1.0 A cm−2 at 1.72 V, showing excellent capability in catalyzing overall water splitting at ampere level. This study, showing a feasible strategy that enables the facile reconstruction to identify active sites, would inspire the development of efficient electrocatalysts for HER and other electrochemical hydrogenation reaction.

Topotactic transformations in Hf-Al-C MAX phase compounds: Synthesis and characterization of nanolaminated Hf2AlC, Hf3AlC2 and Hf5Al2C3

The synthesis of high-purity Mn+1AXn (MAX) phase ceramics in the Hf-Al-C ternary system from near-stoichiometric feedstock powder mixtures has been exceptionally challenging due to the rapid concurrent formation of persistent, ultrafine HfC impurities. This work synthesized ceramics containing the nanolaminated Hf5Al2C3 ‘superstructure’, showing that it comprises alternating Hf2AlC and Hf3AlC2 atomic stackings. For the first time, the Hf5Al2C3 complex structure was associated with the topotactic transformation of Hf2AlC into Hf3AlC2, which is observed upon heating the powder compact to temperatures higher than 1500 °C; moreover, an inverse decomposition reaction of Hf3AlC2 into Hf2AlC was observed as result of further heating the powder compact to temperatures exceeding 1600 °C. The crystal structure and lattice parameters of the Hf5Al2C3 ‘superstructure’ were determined. MAX phase ceramics containing up to 40–45 wt% Hf3AlC2/Hf2AlC were produced with HfC as the main competing phase. The hardness and damage tolerance of these MAX phase ceramics were also evaluated.

Atomic‐Scale Phase Transformation in Perovskite LaCoOx Resistive Switching Memristive Devices

Resistive random‐access memory (RRAM) is considered the next‐generation nonvolatile memory owing to its simplicity, low power consumption, and high storage density. Resistive switching (RS) occurs in a wide range of materials among the transition metal oxides. Herein, an epitaxial ternary metal oxide layer, LaCoOx (LCO), grown on Nb‐doped SrTiO3 substrates, is utilized as an RRAM device. When voltage is applied, it exhibits excellent RS behavior. More than 900 cycles are obtained, and the retention time reaches up to 104 s. To investigate the RS behavior, high‐resolution transmission electron microscopy and atomic‐scale scanning transmission electron microscopy are used to observe the structural evolution and oxygen ion migration in LCO. The structure exhibits a perovskite–brownmillerite topotactic phase transformation from LaCoO2.5 or LaCoO2.67 to the LaCoO3 conductive regions. The reversible transition between the low‐resistance states and high‐resistance states enables the RS mechanism. Additionally, the valence states are confirmed using high‐resolution X‐ray photoelectron spectroscopy. This study not only illustrates the oxygen‐ion migration mechanism of LCO but also demonstrates its suitability for RRAM applications.

Mesocrystalline SrTiO3/CaTiO3 nanocomposites with 3D heteroepitaxial interfaces, superior piezoresponse and high Curie temperature

Ferroelectric mesocrystalline nanocomposites are promising piezoelectric nanomaterials due to the presence of three-dimensional (3-D) heteroepitaxial interfaces, rendering superior piezoelectric and dielectric responses due to lattice strain at the interface. Herein, we describe the synthesis of mesocrystalline SrTiO3/CaTiO3 (ST/CT) nanocomposites via a two-step topochemical process by using layered titanate H1.07Ti1.73O4·nH2O (HTO), as a precursor, and demonstrate the influence of synthesis parameters on nanostructure, morphology, piezoelectric response and dielectric behavior. The mesocrystalline ST/CT nanocomposites are formed by in-situ topotactic structural transformation, consisting of [110]-oriented ST nanocrystals and [001]-oriented CT nanocrystals with high-density 3-D heteroepitaxial interfaces. The presence of 3-D heteroepitaxial interfaces introduces lattice strain at the interface, leading to an enormously enhanced piezoelectric response with a d33* value of 301 p.m./V. Moreover, the Curie temperature of ST phase is significantly increased from −250 °C to 300 °C by introducing lattice strain. It is demonstrated that the piezoresponse depends on lattice mismatch at heteroepitaxial interfaces and optimal lattice mismatch is found to be ∼3.3%, where the largest lattice strain effect and an expected d33* value of about 450 p.m./V could be achieved. These results demonstrate the potential of lattice strain engineering for high-performance lead-free piezoelectric materials.

Valence-Ordered Thin-Film Nickelate with Tri-component Nickel Coordination Prepared by Topochemical Reduction.

The metal-hydride-based "topochemical reduction" process has produced several thermodynamically unstable phases across various transition metal oxide series with unusual crystal structures and nontrivial ground states. Here, by such an oxygen (de-)intercalation method we synthesis a samarium nickelate with ordered nickel valences associated with tri-component coordination configurations. This structure, with a formula of Sm9Ni9O22 as revealed by four-dimensional scanning transmission electron microscopy (4D-STEM), emerges from the intricate planes of {303}pc ordered apical oxygen vacancies. X-ray spectroscopy measurements and ab initio calculations show the coexistence of square planar, pyramidal, and octahedral Ni sites with mono-, bi-, and tri-valences. It leads to an intense orbital polarization, charge-ordering, and a ground state with a strong electron localization marked by the disappearance of ligand-hole configuration at low temperature. This nickelate compound provides another example of previously inaccessible materials enabled by topotactic transformations and presents an interesting platform where mixed Ni valence can give rise to exotic phenomena.

Topotactic transformation of perovskite-based manganite film triggered via simple oxygen getter layer

Stoichiometric composition, in particular, oxygen concentration, is of critical importance for distinct crystalline structures and emergent electronic properties of strongly correlated perovskite oxides. Using manganite La0.7Sr0.3MnO3 as a model system, we study oxygen vacancy (VO) driven regulations of coordination chemistry, crystalline structure and associated physical property of La0.7Sr0.3MnO3 film by means of capping oxygen-deficient binary oxide (Al2O3-δ or TiO2-δ) ultrathin layer. High-efficient migrations of VO at the interface of capped La0.7Sr0.3MnO3 heterostructure give rise to tunable Mn–O coordination units, topotactic transformations and concomitant electronic modulations. A distinct perovskite-brownmillerite (PV-BM) topotactic transformation is observed for the capped La0.7Sr0.3MnO3 film, accompanying by a crossover from ferromagnetic-metallic phase to antiferromagnetic-insulating one. This facile control of oxygen concentration of perovskite-based oxides has significant implications for rational design of functional oxides with unique coordination frameworks, electronic states and emergent performances.

Topotactic transformation of gadolinite‐ to melilite‐type structure revisited

AbstractTopotactic reactions can lead to the formation of new phases, which cannot be obtained via classical synthesis methods. The high‐temperature topotactic transformation of gadolinite‐type compounds, homilite Ca2Fe2+B2Si2O8O2 and datolite Ca2□B2Si2O8(OH)2, into a melilite‐type compound, okayamalite Ca2B2SiO7, was studied by in situ high‐temperature single‐crystal X‐ray diffraction and ex situ Raman spectroscopy. Furthermore, the density functional theory was used to calculate the electronic structures and Raman spectra of datolite, homilite, and okayamalite. At low temperatures (250–500°C), homilite undergoes the Fe oxidation process, whereas at high temperatures, both homilite and datolite transform into okayamalite (750 and 780°C, respectively). The transformation of datolite into okayamalite is a conversion of a single crystal to a polycrystalline aggregate, while the transformation of homilite into okayamalite is a transformation of a single crystal to a single crystal. Datolite derived from okayamalite is similar to natural okayamalite, whereas homilite derived from okayamalite shows Fe3+ for Si/B substitution. The existence of tetrahedrally coordinated Fe3+ leads to a stabilizing effect, resulting in the formation of a single crystal of okayamalite. In addition, the incorporation of iron into the structure of okaymalite leads to a change in the thermal behavior of the compound (α11 = 22 and 15×10−6°C–1 for datolite‐derived and homilite‐derived okayamalites, respectively). However, the thermal expansion of okayamalites is almost isotropic, which is typical for melilite‐type compounds.datolite, high‐temperature, homilite, okayamalite, topotactic reaction

Insights Into the Micromechanics of Dehydration‐Induced Gypsum to γ‐Anhydrite Phase Transition From Instrumented Microindentation Experiments

AbstractGypsum, an anisotropic hydrous mineral, localizes strain through dehydration‐induced embrittlement and hydrodynamic lubrication, affecting the deformation in active tectonic settings. Here, we examine the micromechanical status of syn‐ and post‐dehydration gypsum‐phases, crucial for understanding intra‐crystalline deformation. We micro‐indented the (010) planes of natural gypsum crystals from 30 to 140°C at various strain‐rates to track mechanical changes during progressive dehydration and phase transition. Thermogravimetric analyses reveal that gypsum dehydrates between 100 and 140°C following a sigmoidal curve. Micromechanical data show, at 30°C, the mean hardness of gypsum is 2.42 GPa, reducing to 0.5 GPa at 140°C, after complete dehydration. Following the sigmoidal dehydration trend, elastic modulus, fracture toughness, and yield stress likewise drops with progressive dehydration. The Gypsum‐Hemihydrate phase exhibits strain‐rate sensitive elastoplastic deformation between 30 and 110°C, as hardness decreases with increasing strain‐rate. We propose that delamination of the layers and extensive tensile cracking along [010] cause this strain‐rate sensitive behavior, displaying Indentation Size Effect. Dehydrated phases (Hemihydrate and γ‐Anhydrite) are formed as exfoliated pseudomorphic flakes through topotactic transformation along [010] and show two sets of oppositely dipping slip systems. During the late dehydration stage (120–140°C), plastic strain is accommodated by the sliding of these flakes along with inelastic pore compaction, resulting in strain‐rate insensitive plastic deformation of the system.

Synergistic interfacial electronic modulation of topotactically developed bimetallic CoNiP on NiS nanorods for enhanced alkaline hydrogen evolution reaction.

Designing hybrid transition metal phosphosulfide electrocatalysts is critical for the hydrogen evolution reaction (HER). We propose a novel approach by designing a hierarchical structure of cobalt phosphide (CoP) and nickel phosphide (Ni8P3) nanoparticles topotactically developed on nickel sulfide (Ni3S2) nanorods (CoNiP/NiS) via a sulfuration-phosphorization strategy using conductive 3D nickel foam. Hierarchical heterostructured nanorods were achieved without the need for template removal steps or the assistance of surfactants. This not only simplifies the process but also improves the exposure of active sites for catalytic purposes. Furthermore, the theoretical calculation results revealed that the high H* adsorption-free energy for CoP and Ni8P3 phases significantly decreases upon coupling with Ni3S2, which indicates that the interfacial electronic interaction synergistically modulates both CoP and Ni8P3 (CoNiP) at the coupled interfaces and facilitates the adsorption and desorption of H* intermediates during the HER process. The resulting electrode exhibits excellent performance in the HER catalytic process and shows great performance for further exploration in the urea oxidation reaction (UOR). Our work provides a stepping stone toward rational topotactic transformation of active materials on porous substrates, using electronic structure regulation and heterointerfaces to produce promising electrocatalysts for sustainable, large-scale hydrogen production from water electrolysis.