Increasing CuO Content Research Articles

Insights into the composition-structure-property relationship in P2O5[sbnd]CaO[sbnd]Na2O[sbnd]CuO bio-relevant glasses

Copper-containing calcium phosphate glasses possessing antimicrobial properties have attracted attention for biomedical applications in tissue engineering. Yet, composition-structure-property evaluations linking structural, thermal and optical properties with the oxidation states of copper are lacking. In this work, bio-relevant P2O5CaONa2OCuO glasses were prepared by melting with increasing [CuO]/[Na2O] molar ratios (0.1–1.5), and studied by X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) spectroscopy, thermal/dilatometric analysis, optical transmission, X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The XRD analysis confirmed the non-crystalline structure of the glasses. The FT-IR evaluation indicated that increasing the [CuO]/[Na2O] ratio significantly supports the connectivity of the glass network. The thermal characterization revealed a trend of increase in the glass transition and softening temperatures, while the coefficient of thermal expansion decreased with increasing CuO thus harmonizing with a glass strengthening. The optical evaluation showed substantially decreased transmission from the red toward the near infrared region due to d-d transitions in Cu2+ ions. A significant red shift in the glass transmission edge was also exhibited, wherein a decrease in the optical band gap energies with increasing CuO content was indicated by Tauc plot assessment. Further evaluation of the Urbach energies was performed which suggested increased structural disorder for high [CuO]/[Na2O] ratios. While XPS did not support a trend of increasing contents of non-bridging oxygens in the glasses, it indicated copper occurred most significantly as Cu+ besides Cu2+. It is supported that the decrease in optical band gaps and increase in Urbach energies follows the incorporation of copper ions rather than an increase in non-bridging oxygens. PL spectra showed features ascribed to Cu+ merely for the glass with lowest [CuO]/[Na2O] ratio, whereas an emission quenching was indicated for higher CuO content coherent with a Cu+ → Cu2+ energy transfer.

Polaronic conduction and switching phenomena of amorphous Li2O–CuO–P2O5

This study investigates electrical conductivity of bulk phosphate glasses containing Li2O and CuO, prepared by standard melt quenching technique. Furthermore, static current–voltage characteristic curves at high fields for memory switching behavior were examined. X-ray diffraction patterns for the studied materials revealed the amorphicity of the prepared films. It was observed that the activation energy of the samples lies in the range of 0.53–0.98 eV, depending on composition. The electrical conductivity at room temperature showed a minimum at a certain ratio of Li2O/CuO. Conduction mechanism and observed minimum were explained by small polaron hopping and interaction between polarons and ions. Current–voltage characteristics at high electric field showed memory switching. The mean value of the threshold voltage was found to be dependent on composition which decreased with increase in CuO content. Values of the threshold voltage and activation energy were obtained for the investigated compositions. The observed switching phenomenon was explained by thermal model. • Phosphate glasses with Li2O and CuO were prepared. • Electrical conductivity at room temperature was showed a minimum at a certain ratio of Li2O/CuO. • Current–voltage characteristic of the samples was showed memory switching at high electric field.

Optical properties of CuO/ZnO composites prepared by mechanical grinding

In this work, ZnO and CuO were first prepared by thermal evaporation and direct precipitation, respectively, and then CuO/ZnO composites were obtained by mechanical grinding the mixtures of CuO and ZnO. Scanning electron microscopy, Raman spectroscopy, Raman imaging, UV–vis absorption spectroscopy, and photoluminescence spectroscopy were used to analyze the morphology, structure, and optical properties of CuO/ZnO composites. Raman spectra suggest that the prepared ZnO has a high crystalline quality, while the CuO/ZnO composites have an internal stress. Compared with ZnO, the absorption edge of CuO/ZnO composites shows a red-shift, and the absorption intensity in the visible region is increased greatly. Pure ZnO shows a strong ultraviolet (UV) emission and a weak green emission. As for the CuO/ZnO composites, with the increase of CuO content, the intensity of the UV emission is gradually reduced and the UV peak is gradually moving towards the longer wavelength direction. The decrease in the UV emission intensity should be attributed to interface effects, and the red-shift of UV emission peaks may be caused by unintentional Cu-doping.

Estimation of concentration of nano-sized voids ingrained in CuO doped lithium sulphophosphate amorphous system using positron annihilation spectroscopy

This study is devoted to investigate the effect of Cu ions on the concentration of defect centres like free volume elements (which influence the physical properties of the glasses to a large extent), integrated in exotic lithium magnesium sulphophosphate glasses using positron (e+) annihilation lifetime spectroscopy (PAL) technique. Glasses of a particular composition viz., 20Li2SO4–20MgO–(60-x) P2O5: xCuO (0 ≤x ≤ 1.0 in mol%) were prepared by traditional melt-quenching technique. The analysis of the glass structure by means of spectroscopic studies, indicated that there is a gradual increasing fraction of Cu+ ions with increase of CuO content. The analysis further suggested that Cu2+ ions acted as modifiers in the glass network while Cu+ ions took part network forming position and increased the rigidity of the glass network. Later, positron annihilation decay profiles in the samples were recorded. 22Na isotope (0.1 MBq) was used as the positron source for this study. The obtained decay profiles were resolved in to three components and the corresponding intensity (I) and lifetime (τ) parameters were estimated and their variations with the concentration of CuO were plotted. The plots suggested that among the three intensity components, the third component (even though its contribution to the total intensity is small) exhibited the largest lifetime and further exhibited a decreasing trend with increase of CuO content. Moreover, radius of the cavity (R) and the fraction free volume (fv) entrenched in the glass matrix are found to decrease with increase of CuO concentration. The analysis of results of these studies in combination with the conclusions drawn from dielectric and related studies suggested a gradual decreasing concentration of Oh Cu2+ ions which induce free volume defects by acting as modifiers. Overall analysis of the results of PAL studies suggested increasing content of CuO facilitates the increasing rigidity or increasing corrosion resistance of lithium sulphophosphate glasses.

Optical parameters, antibacterial characteristics and structure correlation of copper ions in cadmium borate glasses

Binary base borate glass of nominal composition (45CdO.55B2O3 mol%) and other samples containing up to 1.6 mol% CuO were successfully prepared using melt annealing route. Fourier transforms infrared (FTIR) spectra of the prepared glasses were studied to identify the structural building groups within the glasses and the role of Cu ions in the matrix arrangement.UV spectra of studied glasses reveal two intense narrow bands originally located at about 235 and 310 nm attributed for the presence of trace iron impurities present on the chemical used for preparation even in the ppm level. Additional analyzed broad visible band centered at about 780 nm appears in the spectra of CuO doped glasses and exhibit splitting at high CuO content. Optical energy gap and other physical parameters including refractive index, density, molar volume, molar refraction, electronic polarizability, and optical basicity reveal strong correlation with copper ion speciation.Both experimental and deconvoluted FTIR spectra of the studied glasses reveal characteristic absorption bands indicating the presence of both triangular and tetrahedral borate groups in their separate vibrational sites. The presence of Cu ions within the doping level is observed to cause no changes in the main characteristic IR bands but limited changes in the intensity of some bands and loosing of the splitting are observed.Antibacterial studies disclose diverse inhibition zone associated with an increase of CuO content and type of bacteria under examination connected with their activity index percent.

Fabrication of lead-free low melting temperature TeO2-V2O5-CuO glasses and wetting behavior on AlN ceramic substrate

The fabrication of novel TeO2-V2O5-CuO ternary glasses has been investigated. The structural role of V2O5 on thermal properties of glass has been explored through Fourier transformed infrared spectra and X-ray diffraction methods. Glass transition temperatures and softening temperatures of as fabricated TeO2-V2O5-CuO ternary glasses were determined by differential scanning calorimeter, reaching minimum value of 296 °C and 310 °C under the corresponding chemical composition with 15 mol% V2O5. As the V2O5/CuO content ratio decreased, thermal expansion coefficient increased from 9.85 × 10−6 K−1 to 10.9 × 10−6 K−1. The valence states of elements have been determined by X-ray Photoelectron Spectroscopy. The practical sealing property of the glasses was characterized by the contact angles on AlN substrates, which declined drastically from 124° to 34° under temperature of 510°C by increasing CuO concentration. The structural and thermal properties as well as wetting behavior make this TeO2-V2O5-CuO ternary glasses a potential candidate to be applied in electronics package.

Optical Spectroscopy and Excited-State Dynamics of Eu3+ -Doped Bismuth Borate Glasses Containing CuO.

Bismuth borate glasses containing phosphors and luminescent rare-earths are of interest for applications in light-emitting devices. Herein, the influence of CuO impurities on red-emitting Eu3+ -doped bismuth borate glasses of the 25Bi2 O3 -15BaO-10Li2 O-50B2 O3 type was investigated by various spectroscopic methods. The glasses were prepared by the melt-quench technique and characterized by X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) spectroscopy, UV/Vis optical absorption (OA), and photoluminescence (PL) spectroscopy including decay kinetics assessment. The XRD data confirmed the amorphous nature of the glasses whereas FT-IR spectra indicated the basic structural features of trigonal BO3 units and BO4 tetrahedra. The OA analysis showed that addition of CuO up to 0.5 mol% results in significant growth of the visible Cu2+ absorption band around 715 nm, with slight decrease in the optical band gap energies assessed through Tauc plots. A drastic PL quenching of Eu3+ ions emission was evidenced concurring with the detrimental effect of Cu2+ . The assessment of the Eu3+ emission decay curves revealed significant lifetime decrease of the 5 D0 emitting state with increasing CuO concentration. An analysis of quenching constants was finally performed comparing results from integrated PL data with the emission decay rates. It is argued that the bismuth borate glass system supports an effective Eu3+ →Cu2+ energy transfer (more so than phosphates) in connection with a strong spectral overlap between Eu3+ emission and Cu2+ absorption.

Phase composition, sinterability and bioactivity of amorphous nano-CaO-SiO2-CuO powder synthesized by sol-gel technique

Nowadays, the advancement of sciences urged the scientists to synthesize nano materials having a good bioactivity. Amorphous nano CaO–SiO2–CuO materials were prepared by sol-gel method and investigated for their phase composition, sinterability and bioactivity. To detect the crystallization temperature, calcination was conducted at different temperatures. Phase composition was examined by XRD and confirmed by FTIR. Bioactivity of prepared powder was assessed through soaking in simulated body fluid (SBF) then examined by FTIR. Also, concentrations of Ca, P, Si and Cu in (SBF) solution were recorded by inductive coupled plasma (ICP). Furthermore, the antibacterial properties were evaluated against S. aureus and S. epidermidis bacteria. The prepared powders were sintered up to 1300 °C and their physico-mechanical properties were studied. The results revealed that the materials calcined at 600 and 800 °C exhibited amorphous character while that calcined at 1000 °C was crystalline in nature. Sintering up to 1300 °C led to production of dense bodies having appropriate physico-mechanical properties. The mechanical properties increased with increasing sintering temperature and decreasing CuO content except fracture toughness which increased with increasing CuO content. Also, the results pointed out that the lower the CuO content in the samples; the higher are their bioactivity and antibacterial behavior. Furthermore, the amorphous ones exhibited better bioactivity than the crystalline ones.

Dielectric characteristics, dipolar relaxation dynamics and ac conductivity of CuO added lithium sulpho-phosphate glass system

In this work we have investigated the influence of copper ions on dielectric characteristics and ac conductivity of lithium sulpho magnesium phosphate glasses. Glass samples were synthesized by melt-quenching and annealing methods. The structural analysis of the glasses is performed by XPS, optical absorption (OA) and IR spectral studies. The XPS and OA spectral studies have revealed increasing fraction of Cu+ ions in the glasses, whereas IR spectral results indicated a growing degree of internal augmentation between various structural units the glass network with increase of CuO content. The dielectric parameters and a.c. conductivity, σac, exhibited decreasing trend while electrical impedance showed an increasing trend with increase of CuO concentration. The dipolar effects exhibited by electrical moduli dispersion spectra were analyzed by Cole-Cole plots. The increased degree of rigidity of the glass network is predicted to be responsible for the observed decrease of σac. The overall analysis of the variation of σac with CuO content indicated a gradual increment in the polaronic component at the expense of ionic component of conductivity. Finally, it is concluded that the studied glass doped with a small concentration of CuO is as useful as electrolyte material in solid-state batteries, whereas higher concentration of CuO is detrimental for such applications.

Dielectric Studies on CuO-Na<sub>2</sub>O-B<sub>2</sub>O<sub>3</sub> Glasses

This work is aimed to shed light on the dielectric behavior of CuO containing glasses, since no publications concerning this issue have been presented before. Different glasses in the binary Na2O-B2O3 system were prepared by melt annealing technique. XRD spectra have shown that the amorphous structure is dominant in all glasses containing mixed concentrations from CuO and Na2O. The crystalline phases appeared only in glass free from Na2O. The dielectric spectroscopy is applied to shed some light on the conduction mechanisms in terms of changing both the dielectric constant and the electrical modulus of the investigated glasses. The ac conductivity increases with increasing frequency and decreases with increasing CuO concentration. Both the dielectric constant and dissipation loss is decreased with increasing frequency. Correlated barrier hopping (CBH) is considered an appropriate conduction mechanism results from the increase of frequency.

Tailoring the optical and dielectric properties of PVC/CuO nanocomposites

The solvent casting method has been applied to prepare PVC/CuO nanocomposite films with CuO ratios (0, 2.5, 5.0, 10.0 and 15.0 wt%). X-ray diffraction (XRD), Fourier transform infrared spectroscopy, optical absorption and dielectric experimental analysis are applied to these nanocomposite films. The CuO nanoparticles have been prepared by using sol–gel method. XRD pattern analysis revealed the formation of CuO (30 nm) single-phase with monoclinic structure and space group C2/c and the amorphous structure of polyvinyl chloride (PVC) matrix. Energy-dispersive X-ray data revealed the increase in CuO content, and scanning electron microscopy morphology analysis approved the dispersion of CuO nanoparticles on the PVC film surface. The optical absorption increased with CuO content, while the transmission decreased. Both direct and indirect energy gaps decrease, while the Urbach energy increases as CuO content increases. The real dielectric permittivity enhanced as the concentration of CuO increased and the imaginary permittivity showed single relaxation at high frequency. The estimated values of both static and high-frequency dielectric constant increased as CuO percentage increases. The presence of CuO causes increase in the loss tangent values for the PVC/CuO polymer films.

Structure, morphology, thermal and electrochemical studies of electrochemically synthesized polyaniline/copper oxide nanocomposite for energy storage devices

Polyaniline (PANI)/copper oxide nano composite (PCN) was synthesized by electrochemical deposition method. The PCN nanocomposite was characterized by using Fourier transform infra-red (FT-IR) spectroscopy, x-ray diffraction (XRD), UV-Visible absorption spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Impedance analyser and electrochemical workstation methods. The FT-IR analysis shows proper chemical interaction of PANI with CuO nanoparticles. In XRD it is found that the amorphousity increases with increasing CuO concentration. The surface morphology observed changes from granular to rod shape structure and TEM gives the particle size range from 30–70 nm. UV-visible spectra shows increase the absorption and decreased the optical band gap with addition of nano composite concentration. The CV curve exhibits rectangular shape with high current density and specific capacitance (Csp) was observed increases with increasing CuO nano concentration at various scan rates from 100–500 mVs−1. The highest specific capacitance (Csp) value 286.66 Fg−1 was obtained for PCN1 nano composite. These results suggest that the PCN nano composite can be used in the energy storage device applications.

ZnFe2O4/CuO core–shell structured nanoparticles: synthesis, structural and magnetic properties

Synthesis of core/shell structured ZnFe2O4/CuO nanoparticles with varying core diameter and different weight percentage of CuO phase [(1−x) ZnFe2O4/x CuO: x = 0.15, 0.30, 0.45 and 0.60] using double stage standard chemical co-precipitation method has been reported in this article. For first four samples only the diameter of core was varied and for other four samples only the weight percentage of CuO phase was varied. The existence of both cubic spinel ZnFe2O4 phase along with monoclinic CuO phase was verified by X-ray patterns recorded at room temperature. The average core diameter was in between 8 and 13 nm as estimated using Scherrer’s formula and further verified by HRTEM images. A reduction in lattice parameter with increasing core thickness and also with increasing CuO phase was observed. A notable enhancement in coercivity and saturation magnetization were observed in field cooled (5 T) hysteresis loops obtained at 5 K for the first four varying core diameter core–shell structured nanoparticles in comparison to bare zinc ferrite nanoparticles of almost same size. A decreasing trend in coercivity and saturation magnetization was also noticed in low temperature hysteresis loops for higher CuO content samples. A considerable improvement in blocking temperature (TB) as well as Neel temperature (TN) for all the different core diameter samples were also found in M(T) protocols. Both blocking temperature and Neel temperature decreased for increasing CuO content in composite nanoparticles. The room temperature M(H) plots exhibited superparamagnetic nature with insignificant coercivity and negligible remanence.

Hydrothermal-assisted synthesis of highly crystalline titania-copper oxide binary systems with enhanced antibacterial properties.

Binary oxide systems containing TiO2 and CuO were synthesized using hydrothermal treatment and shown to have enhanced antibacterial properties. A detailed investigation was made of the effect of the molar ratio of components (TiO2:CuO = 7:3, 5:5, 3:7, 1:9) on the physicochemical parameters and antibacterial activity. Analysis of morphology (SEM, TEM and HRTEM) confirmed the presence of spherical and sheet-shaped particles. On the XRD patterns for the binary oxide materials, two crystalline forms (anatase and monoclinic CuO) were observed. It was found that an increase in CuO content led to a decrease in the BET surface area of the TiO2-CuO binary oxide systems. The synthesized TiO2-CuO materials exhibited very good antibacterial activity against both Gram-positive (methicillin-resistant Staphylococcus aureus and Bacillus cereus) and Gram-negative (Salmonella Enteritidis and Pseudomonas aeruginosa) bacteria. The obtained results show that TiO2-CuO oxide materials may have applications in the biomedical and food industries.

Characterization of borate glasses doped with copper oxide for optical application

Borate glasses having the formula x CuO–(50 − x)B2O3–30Na2O–20ZnO where x = 0, 0.2, 0.5, 1, 4 and 7 mol% were investigated. The samples were prepared using the conventional melt-quenching technique. Physical properties were studied such as; X-ray diffraction, FTIR spectra, and UV–visible transmission. The optical basicity, average electro negativity have been estimated. The estimated optical basicity, unlike electron negativity, exhibits an increase with increasing the CuO content. FTIR spectra show that BO4 ratio decreases with increasing CuO content leading to the formation of non-bridging oxygen’s. Some optical parameters such as the optical band gap, band tail width, crystal field strength and the UV and NIR cut off were determined. The transmission spectrum revealed that the glassy samples containing high content of copper oxide behave as bandpass filters at higher content. The characterized parameters of these filters were found to be highly affected by the addition of CuO. In these glasses the broad absorption band observed at the wavelength 550 nm is characterized by the existence of Cu2+ ions. The optical absorption and ESR studies suggest that, the Cu-ions exist in the Cu2+ state and act as modifiers by increasing the degree of disorder in the glass network. Hence, the present system behaves as a bandpass filter in the ultraviolet–visible region.

Coexistence of ferromagnetism and paramagnetism in ZnO/CuO nanocomposites

In this letter, the room-temperature ferromagnetic behavior in the ZnO/CuO nanocomposites has been reported. The composites composed of ZnO and CuO with different ratios were prepared by hydrothermal method. X-ray diffraction (XRD) and selected area electron diffraction (SAED) confirmed that these composites were made up by wurtzite ZnO and monoclinic CuO. X-ray photoelectron spectroscopy (XPS) indicated that Cu ions on the surface of the materials were in a divalent state. Magnetic measurements showed that all ZnO/CuO composites possessed room-temperature ferromagnetism, while pure ZnO was diamagnetic. With the increase of CuO content in the composites, ZnO/CuO composites displayed the coexistence of ferromagnetism and paramagnetism, and paramagnetism was gradually enhanced and dominated later.

Photocatalytic colour enhancement of Methylene Blue and Rhodamine B dyes by coupled Titania Tenorite nanocomposites

Photocatalytic colour enhancement of Methylene Blue (MB) and Rhodamine B (RhB) dye is achieved by dual band gap Titania Tenorite (TiO2/CuO) nanocomposite system prepared by a cost effective co-precipitation method. The UV–Visible and XPS analyses reveal that the existence of dual band gap is due to the coupling of the constituent metal oxides in the nanocomposite. The band gap of TiO2 in the nanocomposite is tuned to the visible region, by changing the CuO content. Owing to the band gap tuning capability, the nanocomposite can be used from the UV to Visible region for the colour enhancement. The crystalline structure, morphology, molecular structure and chemical bonding of the samples are analyzed by XRD, FTIR and TEM. The PL spectrum shows a reduction in intensity with increase in CuO content. Methylene Blue and Rhodamine B dyes used to check the photocatalytic activity of TiO2/CuO nanocomposite reveals that the dye-metal oxide nanocomposite forms an amazing combination providing a colour enhancement of dye in the presence of light due to the conversion of the dye from its colourless Leuco form to MB or RhB. The mechanism of colour enhancement is well justified by UV–Vis absorption spectra.

Copper-Containing Magnesioferrite in Vesicular Trachyandesite in a Lava Tube from the 2012–2013 Eruption of the Tolbachik Volcano, Kamchatka, Russia

Cu-rich magnesioferrite was found in vesicular basaltic trachyandesite in one of lava tubes (Duplex) that formed during the 2012–2013 eruption of the Tolbachik volcano, Kamchatka. This mineral is commonly associated with hematite, tenorite, halite, sylvite, and Ca-rich silicates (mainly, esseneite and Na-rich melilite) in high-temperature (800–1000 °C) reactionary zones (up to 100 µm) covering vesicular rocks and lava stalactites in the Duplex tube. The mineral relationships of this assemblage indicate the following crystallization sequence: Ca-rich silicates + hematite → Cu-rich magnesioferrite → tenorite → chlorides. This formed due to the reaction of hot gases containing Cu, alkalis, and Cl with solidified lava rock. The composition of magnesioferrite varies strongly in CuO (5.8–17.3 wt %; cuprospinel end-member—15–47 mol %), whereas the contents of other oxides are minor, indicating the main isomorphic substitution is Mg2+ ↔ Cu2+. Compositions with maximal CuO content nominally belong to Mg-rich cuprospinel: (Cu0.48Mg0.41Mn0.09Zn0.02Ca0.02) (Fe3+1.94Al0.03Ti0.02)O4. Increasing CuO content of the Duplex Cu-rich magnesioferrite is reflected in Raman spectra by moderate right shifting bands at ≈700–710 and 200–210 cm−1 and the appearance of an additional band at 596 cm−1. This supports the main isomorphic scheme and may indicate a degree of inversion in the spinel structure.

Studies on bandgap tuning of visible light active heterojunction CuO/ZnO nanocomposites for DSSC application

Hetero-junction CuO/ZnO nanocomposites have been synthesized by simple solution based two-step method in the weight ratios 1:3, 1:2 and 1:1. The crystallite phases of the constituent nanomaterials are confirmed by X-ray diffraction. Increase of CuO content shows significant changes in the absorption spectra with exciton and plasmon related bands of ZnO and CuO, respectively. The compositional analysis and surface chemical states have been probed using X-ray photo electron spectroscopy (XPS). The bandgap is found to decrease with the increase of CuO content. The hybrid system is found to be suitable for absorbing a wide region of incident light with its enhanced absorption characteristics. The synthesized composites show suppression of the broad green band emission from ZnO near to the plasmon band of CuO, enhancing the charge separation which can further minimize charge loss due to recombination. The shift and asymmetry related to Raman bands give a clear idea about the crystallinity and coupling between phonon and continuum level created by the CuO. This coupled system could serve as an efficient photoanode material for dye sensitized solar cells with enhanced efficiency. Among the three composites, 2:1 sample exhibits maximum efficiency.

Compatibility of NiO/CuO in Ca–Cu Chemical Looping for High‐Purity H2 Production with CO2 Capture

AbstractCa–Cu chemical looping is a novel and promising approach for converting methane into pure H2 following the principle of sorption‐enhanced reforming. Its operational efficiency is largely determined by an appropriate coexistence of Cu‐based oxygen carriers and Ni‐based catalysts. Here, NiO/CuO composites are synthesized and their catalytic activity for H2 production is measured using a fixed‐bed reactor system equipped with an online gas analyzer. It is reported that the presence of CuO can hinder the activity of Ni‐based catalysts in H2 production, and experimental results show that the negative effect of CuO is strengthened with increasing CuO content and calcination temperature during sample preparation. With the help of a series of specific test and characterization techniques, interaction rules between NiO and CuO are further investigated and understood, and based on that an action mechanism model is proposed. Furthermore, an arrangement of mixed particles that avoids the intimate contact of CuO/NiO is suggested and tested, and a superior performance is demonstrated while observing no restrictions of CuO on Ni‐based catalysts in sorption‐enhanced steam‐methane reforming under the conditions of Ca–Cu chemical looping.