Oxide Hydroxide Research Articles

Evaluation of local oxygen flux produced by photoelectrochemical hydroxide oxidation by scanning electrochemical microscopy

Several in-situ electrochemical approaches have been developed for performing a localized photoelectrochemical investigation of the photoanode. One of the techniques is scanning electrochemical microscopy (SECM), which probes local heterogeneous reaction kinetics and fluxes of generated species. In traditional SECM analysis of photocatalysts, evaluation of the influence of radiation on the rate of studied reaction requires an additional dark background experiment. Here, using SECM and an inverted optical microscope, we demonstrate the determination of O2 flux caused by light-driven photoelectrocatalytic water splitting. Photocatalytic signal and dark background are recorded in a single SECM image. We used an indium tin oxide electrode modified with hematite (α-Fe2O3) by electrodeposition as a model sample. The light-driven flux of oxygen is calculated by analysis of SECM image recorded in substrate generation/tip collection mode. In photoelectrochemistry, the qualitative and quantitative knowledge of oxygen evolution will open new doors for understanding the local effects of dopants and hole scavengers in a straightforward and conventional manner.

Enrichment mechanisms of Mo in soil in the karst region Guangxi, China

Soils developed in karst regions have naturally high background values of molybdenum (Mo) due to geological factors. However, the enrichment mechanism of Mo in these soils are not fully understood, making it challenging to assess their ecological risk and utilize Mo-rich land resources. To shed light on this issue, this study collected and analyzed data from the 1:50,000 geochemical survey in Guangxi, including 536,503 sets of soil data and 3043 sets of rock data, as well as 40 sets of carbonate rock-soil from typical karst regions. The results showed that soil Mo enrichment is highly correlated with the distribution of carbonate rocks in karst regions. The carbonate rocks in these regions contain Mo ranging from 0.03 to 1.06 mg·kg−1 (with a mean of 0.22 mg·kg−1). In comparison, the soil Mo derived from carbonate rocks can reach up to 6.00 mg·kg−1 (with a mean of 2.75 mg·kg−1), representing an average enrichment of soil Mo that is 24 times higher compared to the carbonate parent rock. The enrichment of soil Mo in karst regions is primarily controlled by secondary enrichment during the weathering process of carbonate. During the insoluble residue accumulation process, the dissolution of carbonate leads to a dramatic reduction in bedrock volume, and the adsorption of clay minerals and Fe minerals in insoluble residues plays an essential role in Mo enrichment during these stages. During the soil-forming stage of the insoluble residue, most Mo leaches into the water body due to the mineral transformation of insoluble residue. Consequently, as Fe–Mn nodules in soils become more enriched with increasing weathering intensity, some Mo is absorbed and passivated by iron and manganese oxides (hydroxides). Accordingly, the contribution of Fe–Mn nodules and the degree of leaching were closely related to the enrichment of soil Mo in karst regions. This study provides insights into the enrichment mechanisms of Mo in soils developed in karst regions, which will help to evaluate their ecological risk in these environments.

Alkylamine-Confined Thickness-Tunable Synthesis of Co(OH)2-CoO Nanosheets toward Oxygen Evolution Catalysis

Thickness regulation of transition metal hydroxides/oxides nanosheets with superior catalytic properties represents a promising strategy to enhance catalytic performance, but it remains an enormous challenge to achieve precise control, especially when it comes to the ultrathin limit (several atomic layers). In this work, a facile strategy of alkylamine-confined growth is proposed for the synthesis of thickness-tunable metal hydroxide/oxide nanosheets. Specifically, ultrathin cobalt hydroxide and cobaltous oxide hybrid (Co(OH)2-CoO) nanosheets (Co-O NSs) with a thickness in the range of 2-6 nm (5-13 atomic layers) are synthesized by using alkylamines with different carbon chain lengths as the ligand to modulate vertical coordination ability. Co-O NSs with a thickness of 2 nm (Co-O NSs-2 nm) exhibit excellent oxygen evolution reaction (OER) performance with an overpotential of 278 mV at 10 mA/cm2. The maximized number of active sites including oxygen vacancies, optimal adsorption strength, and the highest electrical conductivity are considered as the potential factors contributing to the excellent OER performance of Co-O NSs-2 nm. This work holds great significance for the precise thickness-tunable synthesis of transition metal layered hydroxide nanosheets with modulated and improved catalytic performance.

Efficient Removal of Tannic Acid from Olive Mill Wastewater Using Carbon Steel Slag

Mediterranean countries experience a large production of olive oil, thus generating huge quantities of non-biodegradable vegetation waters. The discharge of these effluents into aquatic environments seriously affects the quality of surface waters. This study investigated the potential use of carbon steel slag (SS) as an adsorbent and improver for reducing olive mill wastewater (OMWW) toxicity. The elemental and structural characterization of SS was carried out using inductively coupled plasma-optical emission spectrometry (ICP/EOS), X-ray fluorescence (XRF), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) analysis. OMWW characterization indicated that the effluent was acidic in nature, with a pH of 4.8, a higher conductivity reaching 14.92 mS/cm, higher COD of 157.31 g/L, rich in organic matter 112.33 g/L, and total phenolic compounds of 11.13 g/L. The neutralization capacity of SS was demonstrated by reducing the OMWW’s acidic character. Afterward, the adsorption of tannic acid (TA) was investigated using SS. Parameters such as contact time, initial TA concentration, adsorbent dosage, pH, and temperature were investigated. The kinetic study indicated that the adsorption of TA onto SS fitted well with the second pseudo-order (r = 0.99) and Elovich (r = 0.98) models, indicating that the adsorption of TA was mainly chemical and depends on the reactions of oxide hydrolysis and hydroxides dissolution. Moreover, Langmuir isotherm has greatly described the adsorption of TA on SS (R = 0.997), suggesting that the surface of SS is homogenous, and the adsorption occurs mainly in monolayer. The maximum adsorption capacity reached 714.28 mg/g, indicating the higher capacity of SS to reduce the polyphenolic compounds in OMWW. This study demonstrated that SS residue from the steelmaking industry could present a highly interesting material for OMWW remediation.

Reversible Growth of Halide Perovskites via Lead Oxide Hydroxide Nitrates Anchored Zeolitic Imidazolate Frameworks for Information Encryption and Decryption.

The low formation energies of metal halide perovskites endow them with potential luminescent materials for applications in information encryption and decryption. However, reversible encryption and decryption are greatly hindered by the difficulty in robustly integrating perovskite ingredients into carrier materials. Here, we report an effective strategy to realize information encryption and decryption by reversible synthesis of halide perovskites, on the lead oxide hydroxide nitrates (Pb13O8(OH)6(NO3)4) anchored zeolitic imidazolate framework composites. Benefiting from the superior stability of ZIF-8 in combination with the strong bond between Pb and N evidenced by X-ray absorption spectroscopy and X-ray photoelectron spectroscopy, the as-prepared Pb13O8(OH)6(NO3)4-ZIF-8 nanocomposites (Pb-ZIF-8) can withstand common polar solvent attack. Taking advantage of blade-coating and laser etching, the Pb-ZIF-8 confidential films can be readily encrypted and subsequently decrypted through reaction with halide ammonium salt. Consequently, multiple cycles of encryption and decryption are realized by quenching and recovery of the luminescent MAPbBr3-ZIF-8 films with polar solvents vapor and MABr reaction, respectively. These results provide a viable approach to integrate the state-of-the-art materials perovskites and ZIF for applications in information encryption and decryption films with large scale (up to 6 × 6 cm2), flexibility, and high resolution (approximate 5 μm line width).

Study on the role of AlOOH in fluorescence correction and depth purification of Cyclops water

Protein-like substances produced by biochemical reactions after disinfection of Zooplankton like Cyclops and humic substances in natural water are the main components of NOM (Natural organic matter). To eliminate early warning interference in the fluorescence detection of organic matter in natural water, a clustered flower-like AlOOH (aluminum oxide hydroxide) sorbent was prepared. HA (humic acid) and amino acids were selected as mimics of humic substances and protein-like substances in natural water. The results demonstrate that the adsorbent can selectively adsorb HA from the simulated mixed solution and restore the fluorescence properties of tryptophan and tyrosine. Based on these results, a stepwise fluorescence detection strategy was developed and used in natural water rich in zooplanktonic Cyclops. The results show that the established stepwise fluorescence strategy can well overcome the interference caused by fluorescence quenching. The sorbent was also used for water quality control to enhance coagulation treatment. Finally, trial runs of the water plant demonstrated its effectiveness and suggested a potential control method for early warning and monitoring of water quality.

Effect of CuO species and oxygen vacancies over CuO/CeO2 catalysts on low-temperature oxidation of ethyl acetate

The catalytic oxidation of ethyl acetate (EA) was studied over CuO/CeO2 catalysts which were prepared by ball milling with different precursors (copper oxide, cerium acetate, cerium dioxide, copper acetate and cerium hydroxide). The CuO/CeO2 catalyst (O-A) prepared with copper oxide and cerium acetate as precursors shows very high catalytic activity that 100% EA conversion is achieved at low temperature of 220 °C. It is found that specific surface area (112.8 m2/g), particle size of CuO (3.5 nm) and proportion of oxygen vacancies are prominent on the O-A catalyst. Oxygen vacancies in CeO2 support are beneficial to enhancing the adsorption and activation of the oxygen. More finely dispersed CuO particles and oxygen vacancies which are derived from the synergistic interaction of Cu–Ce species play an important role in the catalytic oxidation of EA.

Iron oxide/hydroxide–nitrogen doped graphene-like visible-light active photocatalytic layers for antibiotics removal from wastewater

Hybrid layers consisting of Fe oxide, Fe hydroxide, and nitrogen doped graphene-like platelets have been synthesized by an eco-friendly laser-based method for photocatalytic applications. The complex composite layers show high photodecomposition efficiency towards degradation of antibiotic molecules under visible light irradiation. The photodecomposition efficiency was investigated as a function of relative concentrations of base materials, Fe oxide nanoparticles and graphene oxide platelets used for the preparation of target dispersions submitted to laser irradiation. Although reference pure Fe oxide/Fe hydroxide layers have high absorption in the visible spectral region, their photodecomposition efficiency is negligible under the same irradiation conditions. The high photocatalytic decomposition efficiency of the nanohybrid layer, up to 80% of the initial antibiotic molecules was assigned to synergistic effects between the constituent materials, efficient separation of the electron–hole pairs generated by visible light irradiation on the surface of Fe oxide and Fe hydroxide nanoparticles, in the presence of conducting graphene-like platelets. Nitrogen doped graphene-like platelets contribute also to the generation of electron–hole pairs under visible light irradiation, as demonstrated by the photocatalytic activity of pure, reference nitrogen doped graphene-like layers. The results also showed that adsorption processes do not contribute significantly to the removal of antibiotic molecules from the test solutions. The decrease of the antibiotic concentration under visible light irradiation was assigned primarily to photocatalytic decomposition mechanisms.

Applicability of a Green Nanocomposite Consisted of Spongin Decorated Cu2WO4(OH)2 and AgNPs as a High-Performance Aptasensing Platform in Staphylococcus aureus Detection.

This study reports the synthesis of a nanocomposite consisting of spongin and its applicability in the development of an aptasensing platform with high performance. The spongin was carefully extracted from a marine sponge and decorated with copper tungsten oxide hydroxide. The resulting spongin-copper tungsten oxide hydroxide was functionalized by silver nanoparticles and utilized in electrochemical aptasensor fabrication. The nanocomposite covered on a glassy carbon electrode surface amplified the electron transfer and increased active electrochemical sites. The aptasensor was fabricated by loading of thiolated aptamer on the embedded surface via thiol-AgNPs linkage. The applicability of the aptasensor was tested in detecting the Staphylococcus aureus bacterium as one of the five most common causes of nosocomial infectious diseases. The aptasensor measured S. aureus under a linear concentration range of 10-108 colony-forming units per milliliter and a limit of quantification and detection of 12 and 1 colony-forming unit per milliliter, respectively. The highly selective diagnosis of S. aureus in the presence of some common bacterial strains was satisfactorily evaluated. The acceptable results of the human serum analysis as the real sample may be promising in the bacteria tracking in clinical samples underlying the green chemistry principle.

A facile aqueous-phase synthesis of Co-based nanostructures composed of cobalt hydroxide and cobalt oxide for enhanced photocatalytic activity of dye-sensitized H2 production

Transition metal catalysts are more cost competitive than noble metal catalysts, but there is a drawback in that catalyst activity must be greatly increased for industrial use. In this research, we report the formation of cobalt-based mixture nanostructures composed of cobalt hydroxide having high photoelectron attracting force, electron transfer ability, and easy access and cobalt oxide having facile charge transfer based on the interchangeability to significantly increase the activity of transition metal-based catalysts. Furthermore, the Co-based nanostructures (CNS) were easily synthesized via an aqueous-phase synthesis, and the molar ratio of α-Co(OH)2/Co3O4 was controlled by simply varying the reaction time. Due to the well-mixed structure of α-Co(OH)2 and Co3O4, which could have a beneficial effect on each other in a photocatalytic reaction, the CNS exhibited 11 times superior hydrogen production than the commercial α-Co(OH)2 in a photocatalytic hydrogen production reaction.

Facile fabrication of nanocomposites of nickel hydroxide and copper oxide for high performance asymmetric supercapacitors

AbstractNowadays, supercapacitors have been among popular electrochemical energy storage devices in modern life. Plenty of active materials have been investigated and developed to meet the increasing demands for high‐performance supercapacitors. In this study, we introduce a facile chemical synthesis route in combination with a subsequent calcination process to fabricate the oxide/hydroxide composites of nickel (Ni) and copper (Cu) as active materials for high‐performance asymmetric supercapacitors. Effects of the composition and calcination temperatures on the electrochemical performance of supercapacitors have been investigated systematically. The optimum composite was the sample calcinated at 200 °C and containing nickel hydroxide and copper oxide with a molar Ni/Cu ratio of 1:1. At a specific current of 1 A.g‐1 the composite electrode could offer a high specific capacitance of 684.2 F.g‐1. In addition, at the higher specific current of 3 A.g‐1 the electrode supplied a relatively high specific capacitance of 526.3 F.g‐1 for the first cycle. After long‐term test of 1000 cycles of charge‐discharge, the electrode maintained 91.7 % of the initial specific capacitance. This suggests the high application potential of synthesized optimum composite for supercapacitors.

Stabilization of As and Heavy Metal-Contaminated Soils by Two Mine Drainage-Treated Sludges

This study explored and analyzed the potential of the practical use of acid mine drainage-treated sludge (AMDS) as a new soil stabilizer for arsenic (As) and heavy metals. Various analyses, toxicity evaluations, and extraction batch experiments were performed to investigate the characteristics of the AMDS as a soil stabilizer and to identify the main mechanisms to fix As and heavy metals on the AMDS in soil. Two types of AMDS, copper metal mine drainage-treated sludge (MMDS) and coal mine drainage-treated sludge (CMDS) and four contaminated soils with different pollution scenarios were used in the experiments. ‘Soil A’ and ‘Soil D’ were mainly contaminated with Cd, Pb and Zn. ‘Soil B’ and ‘Soil C’ were contaminated with As. Results from XRD, XRF, SEM-EDS, TG-DTA, and BET analyses suggested that AMDS is mainly composed of Fe- and Ca- bearing minerals such as CaCO3, Ca(OH)2 and amorphous Fe-oxide (hydroxide), which have a large surface area and high adsorption capacity for As and heavy metals. From batch extraction experiments, the Pb stabilization efficiency of both of the AMDSs in soil A, which has a high Pb and Zn content, was higher than 90%. The high heavy metal stabilization efficiency comes directly from the electrostatic attraction between metal cations and the negatively charged AMDS surface and/or from the co-precipitation of metal oxide (hydroxide) and CaCO3, which occurs comprehensively on the AMDS surface. In the case of Zn, the stabilization efficiency in soil A was somewhat low due to the adsorption competition with Pb, but the Zn stabilization efficiency of the CMDS in soil A was higher than 80% (70% or higher for the MMDS). For soil D, the Zn stabilization efficiency of two AMDSs was higher than 85% because of the lower concentration of other heavy metals in soil D, compared to in soil A. The As stabilization efficiency of the AMDSs in soil contaminated with As (soil B and soil C) was higher than 85%, (mostly > 95%). The overall stabilization efficiency of two AMDSs for heavy metals and As were higher than 75% and 85% (mostly > 90%), respectively, regardless of soil type. We concluded that this high As stabilization efficiency was due to the formation of a new complex by ligand exchange between the Fe- (oxide) hydroxide and the arsenate and also to the cation bridge effect between the AMDS surface and the arsenate as well as the co-precipitation.

Removal of Arsenic(III) from Water with a Combination of Graphene Oxide (GO) and Granular Ferric Hydroxide (GFH) at the Optimum Molecular Ratio

The occurrence of arsenic in water is a global problem for public health. Several removal technologies have been developed for arsenic removal from water, and adsorption onto iron oxy-hydroxides is the most widely used technique. Granular ferric hydroxide (GFH) has been used mainly for As(V) removal, but it has the disadvantage that it can create a problem with the residual concentration of iron in the water. Moreover, graphene oxide (GO), which contains a large amount of reactive oxygen, exhibits high adsorbing capacity. In this study, the combined use of GO and GFH as adsorbent materials in different molar ratios was investigated in order to achieve the maximum As(III) removal from aqueous solutions. The effect of the adsorbent’s dosage, pH value, contact time, initial As(III), and different molar ratios of GO/GFH was examined. As depicted, the presence of GFH enhances the use of GO. In particular, the molar ratio of GO/GFH 2:1 (i.e., 0.2 g/L GO and 0.1 g/L GFH) is chosen as optimal at pH value 7.0 ± 0.1, while the removal percentage increased from 10 % (absence of GFH) to 90% with the simultaneous addition of GFH. Freundlich isotherm and pseudo-second-order kinetic models described the experimental data adequately and the highest adsorption capacity that was achieved was 22.62 μg/g.

New Polymer Composites with Aluminum Phosphates as Hybrid Flame Retardants.

Polymeric aluminum organophosphates are a class of nanostructured aluminum-based compounds that can be considered organic and inorganic hybrid materials. Aluminum phosphates have attracted considerable interest due to their ability to enhance composite materials' mechanical characteristics, lightweight, and thermal properties. Extensive studies have shown the potential of aluminum organophosphates as a component in the development of fire-retardant materials. Aluminum-organophosphorus hybrid (APH) materials have been prepared by reacting aluminum oxide hydroxide (boehmite) with alkyl and aryl phosphoric acids and used to prepare composites with epoxy resin. Boehmite is an aluminum oxide hydroxide (γ-AlO(OH)) mineral, a component of the aluminum ore bauxite. In this work, the composites based on epoxy resin Epidian 601 and commercial curing agent IDA were obtained. Pure boehmite and APH hybrids were added as flame retardants. FTIR and TGA analysis showed that obtained APH possesses a hybrid structure, high thermostability, and various morphologies. These new APH were incorporated into epoxy resin. The infrared spectroscopy confirmed the structure of hybrids and composites. Pyrolysis combustion flow calorimetry (PCFC) and cone calorimeter analyses were performed to assess the flame retardant properties of the composites. The results showed that the incorporation of 17 wt% APH allows a reduction of heat release rate but to a limited extent in comparison to pure boehmite, which is due to the different decomposition mechanisms of both boehmite and hybrids. The cone calorimetry test showed that residue contents correspond quite well to the mineral fraction from boehmite only. The hybrid APHs appear no more efficient than pure boehmite because the mineral fraction in APH is reduced while phosphate fraction cannot promote significant charring.

Crystallographic characterization of bio-waste material originated CaCO3, green-synthesized CaO and Ca(OH)2

Municipal inorganic waste material (eggshell), which was chosen as the source of calcium carbonate, was utilized to synthesize two industrially valuable inorganic compounds, calcium oxide and calcium hydroxide following a sustainable synthesis method. The crystallographic parameters such as lattice parameter, unit cell volume, crystallite size, microstrain, dislocation density, relative intensity, crystal growth preference, and crystallinity index of raw eggshell, calcium oxide, and calcium hydroxide were explored based on the X-ray diffraction. The polymorphic mole fraction of calcite, vaterite, and aragonite in natural eggshells was also estimated. Crystallite size was calculated with the assistance of the Scherrer equation along with Williamson–Hall Method, Monshi-Scherrer Method, and Liner straight-line method of Scherrer’s equation. A relationship among the crystal growth preference, dislocation density, and microstrain was established for the considering compounds. The raw eggshells and synthesized products were also characterized with the aid of Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared (FTIR), and Scanning Electron Microscopy (SEM).

A highly sensitive and ecofriendly assay platform for the simultaneous electrochemical determination of rifampicin and isoniazid in human serum and pharmaceutical formulations

Simple fabrication of an electrochemical sensor for simultaneous determination of rifampicin and isoniazid based on electrochemical modification of SPCE surface with reduced graphene oxide and nickel hydroxide film (Ni(OH)2/rGO/SPCE) without using toxic chemical agents.

A novel method for synthesizing one or two-dimensional metal oxide (hydroxide) nanomaterials using deep eutectic solvents

Metal-based DESs were employed as raw materials and media to fabricate one- or two-dimensional nanomaterials, such as FeO(OH) rod bundle, Co(OH)2nanoplate, ZnO nanorod, and CuO nanoplate.

МЕХАНІЗМ СТРУКТУРОУТВОРЕННЯ СПУЧЕНОГО ШАРУ ПІНОКОКСУ ПРИ ВПЛИВІ МІНЕРАЛЬНИХ РЕЧОВИН

The studies have established the effect of fillers on the performance of the fireproof coating, the parameters of its swelling under the influence of temperature and inhibition, which makes it possible to influence this process. The effect of fillers on the coefficient of swelling of coatings based on inorganic and organic substances during thermal exposure was investigated. It isproved that it consists in the creation of a layer on the surface of the material that prevents heating to a critical temperature and decomposition of the material. Experimental studies have confirmed that the introduction of titanium oxide and aluminum hydroxide in the amount of 5% contributes to the achievement of the highest value of the coefficient of swelling - up to 47, which is 1.11 times higher than the value of the coefficient of swelling when aluminum hydroxide is introduced, titanium oxide and talc in the amount of 3.3%, 1.12 times higher than the value of the coefficient of swelling when titanium oxide and talc in the amount of 5% were added, and 1.08 times higher than the value of the coefficient of swelling when aluminum hydroxide and talc in the amount of 5% were added. The influence of fillers under the action of high-temperature heat flow on the change in the process of swelling of the fireproof coating was established and the mechanism of the kinetics of the fillers' action, characterized by a decrease in speed and mass loss, was determined. Thus, at 700 °C, the introduction of fillers leads to theformation of refractory compositions that prevent the burnout of the resulting foam coke, which increases the efficiency of fire protection of building structures. On the basis of physicochemical research methods, it is shown that the introduction of a mixture of titanium dioxide and aluminum hydroxide in the amount of 5% each into the composition of the organic-inorganic composition leads to an increase in the coefficient of swelling, orderliness of the structure of the foam coke layer, and an increase in its heat resistance due to the dehydration of mixed titanium-aluminum phosphates.

Efficient removal of antimonate and antimonite by a novel lanthanum-manganese binary oxide: Performance and mechanism.

Antimony is a highly toxic pollutant and its removal from water gains increasing attention. To effectively remove both Sb(III) and Sb(V), a novel lanthanum-manganese binary oxide (L1M2BO) adsorbent was synthesized by a simple oxidation coupled with precipitation method. The as-prepared L1M2BO was detailedly characterized by the XRD, SEM, TEM, BET, FTIR and XPS techniques. It is amorphous and irregular in shape, with a particle size of 50-100nm and a specific surface area of 180.4m2/g. A remarkable synergistic effect between the lanthanum hydroxide and Mn oxide in improving antimony adsorption is shown. The maximum adsorption capacities of Sb(III) and Sb(V) are 364.6mg/g and 131.1mg/g at pH 7.0, respectively, which outcompete most of reported adsorbents. The adsorption behaviors of antimony fitted well the pseudo-second-order kinetic and Freundlich models. The adsorption mechanism of Sb(V) involves mainly the replacement of surface metal hydroxyl and forming inner-sphere complex. While the Sb(III) removal is a more complicated process, containing both Sb(III) adsorption and oxidation to Sb(V). Furthermore, the spent L1M2BO sorbent can be regenerated and reused. The L1M2BO could be used as an attractive adsorbent for antimony removal, owing to its easily fabrication, high effectiveness and reusability.

Structural Framework-Guided Universal Design of High-Entropy Compounds for Efficient Energy Catalysis

High-entropy compounds with extraordinary properties due to the synergistic effect of multiple components have exhibited great potential and attracted extensive attention in various fields, including physics, mechanical property analysis, and energy storage. Achieving universal stability and synthesis of high-entropy compounds with a wide range of components and structures continues to be difficult due to the high complexity of multicomponent mixing. Here, we propose a design strategy with high generality for realizing the stability and synthesis of high-entropy compounds that one metal site like the framework in the compound structures with bimetallic sites stabilizes another site to accommodate different elements. Several typical metal compounds with bimetallic sites, including perovskite hydroxides, layered double hydroxide, spinel sulfide, perovskite fluoride, and spinel oxides, have been synthesized into high-entropy compounds. High-entropy perovskite hydroxides (HEPHs) as representative compounds have been synthesized with a highly wide range of components even a septenary component and exhibit great oxygen evolution activity. Our work provides a design platform to develop more high-entropy compound systems with promising development potential for electrocatalysts.