Nickel Precursor Research Articles

Unveiling Catalytic Sites in a Typical Hydrogen Photogeneration System Consisting of Semiconductor Quantum Dots and 3d-Metal Ions.

Semiconductor quantum dots (QDs) in conjunction with non-noble 3d-metal ions (e.g., Fe3+, Co2+, and Ni2+) have emerged as an extremely efficient, facile, and cost-effective means of solar-driven hydrogen (H2) evolution. However, the exact structural change of the active sites under realistic conditions remains elusive, and the mechanism of H2 evolution behind the remarkable activity is poorly understood. Here, we successfully track the structural variation of the catalytic sites in the typical H2 photogeneration system consisting of CdSe/CdS QDs and 3d-metal ions (i.e., Ni2+ used here). That is, the nickel precursor of Ni(OAc)2 changes to Ni(H2O)62+ in neutral H2O and eventually transforms to Ni(OH)2 nanosheets in alkaline media. Furthermore, the in operando spectroscopic techniques of electron paramagnetic resonance and X-ray absorption spectroscopy reveal the photoinduced transformation of Ni(OH)2 to a defective structure [Nix0/Ni1-x(OH)2], which acts as the real catalytic species of H2 photogeneration. Density functional theory (DFT) calculations further indicate that the surface Ni-vacancies (VNi) on the Ni(OH)2 nanosheets enhance the adsorption and dissociation of H2O molecules to enhance the local proton concentration, while the Ni0 clusters behave as H2-evolution sites, thereby synergistically promoting the activity of H2 photogeneration in alkaline media.

Sacrificial template synthesis of hierarchical nickel hydroxidenitrate hollow colloidal particles for electrochemical energy storage

Synthesis of hollow colloidal particles with a well-defined structure in a single step is challenging and highly desired for numerous applications. We propose a simple and productive approach to synthesize hierarchical nickel hydroxidenitrate hollow colloidal particles (NiHNHCP) with tunable structure and property via a one-pot manner for the application in supercapacitor. In this approach, the formation of the NiHN shells and the dissolution of the melamine-formaldehyde (MF) template particles occur simultaneously and successively under a solvothermal condition with time. It is found that the nickel precursors can protonate the solvent, declining the pH and further causing the dissolution of the MF particles. Meanwhile, the nickel precursors transform into NiHN nanosheets that self-assemble into hierarchical shells exclusively at the surface of the MF particles. With the reactions proceeding, the NiHNHCP are yielded ultimately. These NiHNHCP are characterized with superior electrochemical performance, making them practically useful in the application of supercapacitor.

Ethylene Oligomerization over Nickel Supported Silica-Alumina Catalysts with High Selectivity for C10+ Products

The nickel (II) loading silica-alumina under various treatments in terms of aging temperature, Si/Al ratio and activation temperature were investigated by XRD, N2 adsorption-desorption, TEM, UV-Vis, NH3-TPD and XRF and then applied to catalyze the ethylene oligomerization. High aging temperature, low Si/Al ratio and high activation temperature were beneficial to high selectivity for C10+ products because of a reasonable match between Ni active sites and acid sites, high Ni loading content and less octahedral coordination Ni2+ species, respectively. Ni loading content was more important than the number of acid sites for high yield of C10+ products, and less octahedral coordination Ni2+ species favored less by-products produced at high reaction temperature. In addition, other experimental conditions, such as reaction temperature, weight hourly space velocity (WHSV) and nickel precursor were discussed in the paper.

SYNTHESIS, CHARACTERIZATION AND PHOTOCATALYTIC APPLICATIONS OF p(Aac) MICROGELS AND ITS COMPOSITES OF Ni DOPED ZnO NANORODS

ZnO nanorods and Ni doped ZnO nanorods with various concentration of nickel 0%, 5%, 10%, 15%, 20%, 25% were prepared by co-precipitation method. By added zinc acetate dehydrate and nickel nitrate as zinc and nickel precursor in presence of Ammonia solution. Microgels of p(AAc) and its composites of Ni doped ZnO nanorods were synthesized by inverse phase polymerization method under N2 gas atmosphere. Optical structure and morphology of Ni doped ZnO nanorods and its composite with p(AAc) were determined by XRD, TEM, SEM, FTIR and UV-Visible spectrometer. The photocatalytic activity of the samples was testified by using Tungsten lamp of 500 W via photo-degradation of methylene blue (MB) as a standard dye. It was observed that the composite of p(AAc) microgels with Ni doped ZnO nanorods show much enhanced photocatalytic performance as compared to any other individual particle acting as alone. The enhanced photocatalytic activity is due to enhanced surface area, surface roughness and decreasing band gap.

Facile Preparation of Ni-Co Bimetallic Oxide/Activated Carbon Composites Using the Plasma in Liquid Process for Supercapacitor Electrode Applications.

In this study, a plasma in a liquid process (PiLP) was used to facilely precipitate bimetallic nanoparticles composed of Ni and Co elements on the surface of activated carbon. The physicochemical and electrochemical properties of the fabricated composites were evaluated to examine the potential of supercapacitors as electrode materials. Nickel and cobalt ions in the aqueous reactant solution were uniformly precipitated on the AC surface as spherical nanoparticles with a size of about 100 nm by PiLP reaction. The composition of nanoparticles was determined by the molar ratio of nickel and cobalt precursors and precipitated in the form of bimetallic oxide. The electrical conductivity and specific capacitance were increased by Ni-Co bimetallic oxide nanoparticles precipitated on the AC surface. In addition, the electrochemical performance was improved by stable cycling stability and resistance reduction and showed the best performance when the molar ratios of Ni and Co precursors were the same.

α- and β-Phase Ni-Mg Hydroxide for High Performance Hybrid Supercapacitors.

Mg-substituted α- and β-phase nickel hydroxides with high specific capacitance and good stability have been synthesized via sacrificial metal-based replacement reaction. 2D α- and β-phase nickel-magnesium hydroxide (NiMg-OH) have been synthesized by sacrificing magnesium (Mg) powder with nickel salt aqueous solutions. Interestingly, the phase of the obtained NiMg-OH can be controlled by adjusting the nickel precursor. As well, the Mg powder is used not only as Mg source but also alkali source to form NiMg-OH. The α-phase nickel-magnesium hydroxide sample (α-NiMg-OH) exhibits lager surface area of 290.88 m2 g–1. The electrochemical performances show that the α-NiMg-OH presented a superior specific capacitance of 2602 F g–1 (1 A g–1) and β-phase nickel-magnesium hydroxide sample (β-NiMg-OH) exhibits better stability with 87% retention after 1000 cycles at 10 A g–1. The hybrid supercapacitor composed of α-NiMg-OH and activated carbon (AC) display high storage performance and cycle stability, it presents 89.7 F g–1 (1 A g–1) and of 0–1.6 V potential window and it maintains capacitance retention of 84.6% subsequent to 4000 cycles.

Bimetal Co8Ni2 catalyst supported on chitin-derived N-containing carbon for upgrade of biofuels

Non-noble bimetallic Co8Ni2/NC nanoalloy catalyst is prepared through impregnation of cobalt and nickel precursors on nitrogen doped carbon derived from sustainable chitin. Compared to monometallic Co or Ni catalyst and other reported materials, Co8Ni2/NC catalyst exhibits excellent catalytic activity, high selectivity and good stability towards vanillin hydrodeoxygenation to obtain 2-methoxy-4-methylphenol (MMP), a promising way of upgrade biofuel. Characterizations indicate that the active f.c.c. phase of metal alloy can be generated under the induction of nickel component. Kinetic experiment suggests that the activation energy vanillin alcohol over bimetal catalysts are lower than pure nickel or cobalt catalyst, confirming that the synergetic effect between cobalt and nickel also improve its higher catalytic activity.

Porous Nickel‐Alumina Derived from Metal‐Organic Framework (MIL‐53): A New Approach to Achieve Active and Stable Catalysts in Methane Dry Reforming

AbstractAn Al‐containing MIL‐53 metal‐organic framework with very high surface area (SBET=1130 m2.g−1, N2 sorption) was used as sacrificial template to prepare a nickel‐alumina‐based catalyst (Ni0AlMIL) highly active and stable in the reaction of dry reforming of methane (DRM). The procedure consisted in impregnating the activated (solvent free) MIL‐53 sample with a nickel precursor solution, then calcining the material to remove the organic linkers and subsequently reducing it to form the reduced nickel active phase. At the step of calcination, this procedure results in the formation of a porous uniform spinel phase with Ni nanospecies embedded in the alumina‐based matrix, as deduced from XRD, TPR and TEM analyses. This leads after reduction to a porous lamellar γ‐Al2O3 material with small Ni0 nanoparticles homogeneously dispersed and stabilized within the support. The performances of this catalyst in DRM are better than those of two reference Ni/alumina catalysts prepared for comparison by conventional nickel impregnation of two preformed alumina supports: a first one obtained by calcination of MIL‐53 (AlMIL) and a second one consisting of a commercial γ‐Al2O3 batch (AlCOM). Under steady state conditions at a temperature of 650 °C and a pressure of 1 bar, the higher CH4 and CO2 conversions (till 3 times higher than on Ni0/AlCOM), high catalytic stability (no loss of activity after 13–100 h) and higher selectivity towards DRM (H2:CO products ratio remaining at 1) on Ni0AlMIL compared to the other catalysts is believed to come from the particularly strong interaction between the nickel and alumina phases generated by using the unique high specific surface of the parent MOF support to deposit nickel. This creates an intimate mixing favorable to a persisting interaction of the nickel nanoparticles with the alumina support in the reduced material. The lamellar shape of the γ‐Al2O3 composing the catalyst and its remaining high specific surface may also contribute to the excellent Ni resistance to sintering and in turn to the inhibition of carbon nanotubes formation during the reaction.

Plant-based synthesis of NiO nanoparticles using salvia macrosiphon Boiss extract and examination of their water treatment

The goal of this study was to synthesize nickel oxide nanoparticles (NiO-NPs) by the sol–gel method, which involved the use of salvia macrosiphon Boiss plant extract, Ni(NO3)2·6H2O as a capping agent, and a nickel precursor, respectively. The synthesized NiO-NPs were characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible (UV–Vis) spectrophotometer, X-ray diffraction (XRD), field electron scanning electron microscopy (FESEM)/energy-dispersive X-ray spectroscopy (EDX), thermo-gravimetric analysis/differential thermal analysis (TGA/DTA) and vibrating sample magnetometer (VSM) analyzes. Also, according to the results of UV–Vis, the gap band of nanoparticles was calculated to be in the range of about 2.9–3.9 eV. The photocatalytic activity of nanoparticles on methylene blue (MB) degradation was investigated and according to the results, about 80% MB was apparently degraded in the presence of NiO-NPs under UV-A light (11 W) after 5 h in pH ~ 11. We have evaluated the cytotoxicity of NiO-NPs on the multiple tumor cells by materials method, and all the utilized concentrations were observed to cause non-toxic effects; therefore, it can be suggested that these samples have the potential of being employed in different fields of medicine.

Defining nickel phosphides supported on sodium mordenite for hydrodeoxygenation of palm oil

Palm oil is largely produced in Thailand and sufficient to utilize as a biofuel feedstock through hydrodeoxygenation (HDO). In this work a new bifunctional catalyst consisting of nickel phosphide supported on zeolite mordenite in sodium form (Ni-P/NaMOR) was prepared by sequential impregnation and characterized extensively by several techniques to understand the reduction behavior, phases and distribution of nickel phosphides on the support. Nickel and phosphate precursors were transformed to Ni2P2O7 species by calcination and to a mixed phase between Ni12P5 and Ni2P by reduction. The phosphide species distributed in the zeolite cavities and external surface. The HDO of palm oil was tested in a down-flow stainless steel trickle bed reactor and the atmosphere was hydrogen. The mixed phase of nickel phosphides enhanced the HDO reaction. When tested by various temperatures and pressures, the optimum condition in this work was at 425 °C and 50 bar in which a complete of palm oil conversion, the largest HDO yield and selectivity toward C15-C18 alkanes were obtained. The green diesel and HDO yields from reduced Ni-P/NaMOR were larger than those from pure Ni2P and mixed Ni2P-Ni12P5. Interestingly, a small amount of isoparaffins was also observed likely due to the contribution of NaMOR support.

Formation of Ni–MoS3 Hollow Material with Enhanced Activity in Slurry-phase Hydrogenation of Heavy Oil

A kind of Ni–MoS3 material with a prismlike hollow structure was prepared through three steps: the preparation of a nickel precursor, the preparation of a NiMoS4 hollow structure intermediate product, and the annealing treatment of NiMoS4. Then, the catalytic activity of this material in slurry-phase hydrogenation of heavy oil was evaluated. Characterization results indicated that under suitable preparation conditions, the prepared hollow material with a Mo content of 23.40 wt % and a Ni content of 7.08 wt % had a length of approximately 340 nm, a width of approximately 300 nm, and a shell wall thickness of approximately 10 to 20 nm. Moreover, in addition to Ni, Mo, and S, the surface of the material also contained O and C, and the Mo4+ on the surface of this hollow material accounted for 77.24 wt % of the surface Mo atoms, which indicated that more Mo4+ with higher hydrogenation activity may be stably present on the surface of this hollow material than Mo in other valence states. In the slurry-phase hydr...

A simple sonochemical assisted synthesis of NiMoO4/chitosan nanocomposite for electrochemical sensing of amlodipine in pharmaceutical and serum samples.

In this investigation, a facile sonochemical route has been developed for the preparation of porous nickel molybdate nanosheets/chitosan nanocomposite (NiMoO4/CHIT) by using ammonium molybdate and nickel(II) acetate tetrahydrate and as nickel and molybdate precursor, respectively (ultrasonic power 60 W/cm2 and frequency 20 kHz). The ultrasonic based materials preparation as a fast, convenient and economical approach has been widely used to generate novel nanomaterials. Herein, we report an efficient voltammetric sensor for amlodipine drug by using porous nickel molybdate nanosheets/chitosan nanocomposite (NiMoO4/CHIT). Its structure and properties were characterized by x-ray diffraction pattern, scanning electron microscope, transmission electron microscope, elemental analysis and mapping. The electrochemical studies are indicated the NiMoO4/CHIT modified glassy carbon electrode (GCE) exhibited the good performance towards electrocatalytic sensing of amlodipine drug. Consequently, a linear correlation between the anodic peak current with sensor concentration 0.025-373.6 µM with a detection limit and sensitivity of 4.62 nM and 4.753 µA·µM-1·cm-2, respectively. A voltammetry based drug analysis was found to be high sensitive and reproducible, which able to detect nanomolar concentration. Furthermore, the fabricated electrochemical sensor was applied in drug and biological samples.

Improved hydrogen storage properties of Mg/MgH2 thanks to the addition of nickel hydride complex precursors

In order to improve the hydrogenation/dehydrogenation properties of the Mg/MgH2 system, the nickel hydride complex NiHCl(P(C6H11)3)2 has been added in different amounts to MgH2 by planetary ball milling. The hydrogen storage properties of the formed composites were studied by different thermal analyses methods (temperature programmed desorption, calorimetric and pressure-composition-temperature analyses). The optimal amount of the nickel complex precursor was found to be of 20 wt%. It allows to homogeneously disperse 1.8 wt% of nickel active species at the surface of the Mg/MgH2 particles. After the decomposition of the complex during MgH2 dehydrogenation, the formed composite is stable upon cycling at low temperature. It can release hydrogen at 200 °C and absorb 6.3 wt% of H2 at 100 °C in less than 1 h. The significantly enhanced H2 storage properties are due to the impact of the highly dispersed nickel on both the kinetics and thermodynamics of the Mg/MgH2 system. The hydrogenation and dehydrogenation enthalpies were found to be of −65 and 63 kJ/mol H2 respectively (±75 kJ/mol H2 for pure Mg/MgH2) and the calculated apparent activation energies of the hydrogen uptake and release processes are of 22 and 127 kJ/mol H2 respectively (88 and 176 kJ/mol H2 for pure Mg/MgH2). The change in the thermodynamics observed in the formed composite is likely to be due to the formation of a Mg0.992Ni0.008 phase during dehydrogenation/hydrogenation cycling. The impact of another hydride nickel precursor in which chloride has been replaced by a borohydride ligand, namely NiH(BH4)(P(C6H11)3)2, is also reported.

Hydrogenation of toluene over nickel nanoparticles supported on SBA-3 and AlSBA-3 materials

Pure siliceous and aluminosilicate mesoporous molecular sieves of SBA-3 type were used as supports for nickel catalysts obtained via wet impregnation (1 wt.%). Characterization of obtained materials was performed by means of X-ray diffraction (XRD), X-ray fluorescence (XRF), low-temperature nitrogen adsorption/desorption (BET), temperature-programmed desorption of ammonia (TPD-NH3), hydrogen chemisorption measurements and temperature-programmed reduction with hydrogen (TPR-H2). The effect of nickel precursor (nickel nitrate or nickel acetate) and chemical composition of support (SBA-3 and AlSBA-3) on catalytic activity of prepared materials in toluene hydrogenation was studied. It was found that the catalysts obtained using nickel nitrate showed better preserved mesoporous structure with higher dispersion of Ni particles than catalysts obtained from nickel acetate. The use of AlSBA-3 as a support causes the formation of Ni particles with lower dispersion in comparison to the catalysts supported on SBA-3. The activity of nickel catalysts supported on the AlSBA-3 (especially the catalyst obtained using nickel nitrate) for toluene hydrogenation was higher than that of the catalyst supported on SBA-3 despite the lower Ni dispersion. The obtained results bring to conclusion that catalytic activity for toluene hydrogenation is significantly influenced by textural and chemical properties of the support.

Facile Synthesis, Characterization and Electrochemical Performance of Nickel Oxide Nanoparticles Prepared by Thermal Decomposition

Spherical-like nickel oxide (NiO) nanoparticles with the average crystallite sizes of 17.9 nm were synthesized by calcination of a new nickel precursor prepared by mixing of NiCl2*6H2O and oxalic acid weight ration 1:1 in the aqueous solution of 1 molar KOH. X-ray powder diffraction (XRD) pattern, transmission electron microscopy (TEM) image and electrochemical properties of the NiO products were studied. The results indicate that NiO product shows good electrochemical reversibility and exhibits suitable performance with specific capacitance of 982 mA h-1 after 35 cycles at current density of 100 mA g-1.

Development of carbon coated NiS2 as positive electrode material for high performance asymmetric supercapacitor

Facile synthesis of carbon coated NiS2 composite through one-step hydrothermal process was demonstrated. Three different composites were synthesized (NCC1, NCC2, and NCC3) by changing the stoichiometric ratio of nickel, sulphur and carbon precursor. The particle size and its distribution depend on the amount of carbon precursor and metal sulphides ratio. The carbon coating on metal sulphides significantly augmented the electrochemical properties of the supercapacitor electrodes. It was found that in an optimum ratio of carbon precursor and metal sulphide, the particles were formed uniformly as seen in the NCC2 composites and exhibited the specific capacitance of 2212 F g−1 at a specific current of 2 A g−1 in a three-electrode system. An asymmetric supercapacitor (ASC) device was fabricated with NCC2 as positive electrode and thermally reduced graphene oxide as negative electrode. The ASC device showed high specific capacitance of 184.9 F g−1 at 3 A g−1 and specific energy of 50.35 Wh Kg−1 at a specific power of ~2.26 kW kg−1. It showed ~83% retention in specific capacitance after 6000 charge-discharge cycles. High specific capacitance, specific energy and specific power of the ASC device confirmed that the NCC2 composite could be used as energy storage electrode materials for supercapacitor applications.

A self-supported electrode as a high-performance binder- and carbon-free cathode for rechargeable hybrid zinc batteries

Developing highly efficient and flexible air-breathing electrodes is of significant importance for various energy conversion and storage technologies. In this work, we report the synthesis of the self-supported sandwich-structured electrode with Co3-xNixO4/Co3O4 nanowire arrays (NS@Co3-xNixO4/Co3O4). This novel nanostructure demonstrates very high reversible Faradaic redox reaction of CoNi−O ↔ CoNi−O−OH and excellent bifunctional activity toward both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Moreover, the air cathode, prepared by pressing the stainless steel (SS)@Co3O4 sandwiched between two Ni foam (NF)@Co3-xNixO4, possesses a dense and interconnected structure with a high loading of active catalyst. The Ni foam in this work not only acts as a substrate, but also serves as a nickel precursor for the formation of the Co3-xNixO4 catalyst. Meanwhile, combining the 3D porous structure of NF and intrinsic high OER activity of SS, the assembled porous air electrode can take full advantage of the sandwich structure to promote the electrocatalytic reaction kinetics of NS@Co3xNixO4/Co3O4. Rechargeable battery system assembled from this NS@Co3-xNixO4/Co3O4 electrode based on both Zn−Co3-xNixO4 and Zn−air electrochemical reactions exhibits much higher energy efficiency and durability than those of commercial Pt/C and RuO2 electrocatalysts. This protocol opens a new avenue for the rational design of highly efficient and stable self-supported air electrode for metal-air batteries.

A study of synergistic effect on oxygen reduction activity and capacitive performance of NiCo2O4/rGO hybrid catalyst for rechargeable metal-air batteries and supercapacitor applications

An effective non-precious bare NiCo2O4 (NCO) micro-shrubs and graphene (rGO) supported hybrid catalysts (NCO/rGO) were prepared by a simple urea assisted one-pot hydrothermal route. The authors were motivated to investigate an influence of synergistic effect between NCO nanoparticles and rGO sheets of freshly prepared hybrid catalysts (NCO/rGO) by adjusting the starting metal (nickel & cobalt nitrate hexahydrate) precursors, which has been denoted as 50 NCO/rGO, 100 NCO/rGO & 150 NCO/rGO in the present work. All the freshly prepared rGO, NCO and rGO supported hybrid catalysts with three different NCO mass loading samples were characterized through different characterization techniques such as XRD, FT-Raman, HR-SEM, HR-TEM, LSV, CV and galvanostatic charge/discharge studies, respectively. Among them, the rGO supported hybrid catalyst with lower amount of NCO mass loading (50 NCO/rGO) exhibits an outstanding oxygen reduction reaction (ORR) activity with lower onset potential, high limiting current density via. four-electron mechanism in an O2-saturated 0.1 M KOH electrolyte solution at room temperature. In addition, the specific capacitance of hybrid electrode is found to be 1305 F g-1 at a scan rate of 5 mV s−1 with 89% retention of cyclic stability even after 3000 cycles. The observed electrocatalytic activity and capacitive performances of an optimized hybrid sample (50 NCO/rGO) is strongly indicates an influence of better synergistic effect between NCO nanoparticles and rGO nanosheets. Hence, an optimized rGO supported hybrid catalyst (50 NCO/rGO) could be a promising electrocatalyst as well as hybrid electrode for metal-air batteries and supercapacitor applications, respectively.

One-Electron Reduction of Acenaphthene-1,2-Diimine Nickel(II) Complexes.

New nickel-based complexes of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) with BF4 - counterion or halide co-ligands were synthesized in THF and MeCN. The nickel(I) complexes were obtained by using two approaches: 1) electrochemical reduction of the corresponding nickel(II) precursors; and 2) a chemical comproportionation reaction. The structural features and redox properties of these complexes were investigated by using single-crystal X-ray diffraction (XRD), cyclic voltammetry (CV), and electron paramagnetic resonance (EPR) and UV/Vis spectroscopy. The influence of temperature and solvent on the structure of the nickel(I) complexes was studied in detail, and an uncommon reversible solvent-induced monomer/dimer transformation was observed. In the case of the fluoride complex, the unpaired electron was found to be localized on the dpp-bian ligand, whereas all of the other nickel complexes contained neutral dpp-bian moieties.

One-step synthesis of metallic Ni–C/Al2O3 directly applied for CO2 reforming of CH4

In this work, the vacuum co-impregnation of glucose and nickel precursor followed by the carbonization in an inert gas was developed as a new method for the preparation of the directly reduced Ni-based catalysts (Ni–C/Al2O3), which can be directly applied for CO2 reforming of CH4 (CRM) without any reduction. The materials were characterized by XRD, TEM, and N2 adsorption-desorption at low temperature. The results showed that H2 and CH4 derived from the decomposition of the glucose acted as the reducing agents for synthesizing metallic Ni from Ni precursors, and the reduction content of nickel was strongly dependent on the amount the glucose. The introduction of carbon derived from decomposition of glucose decreased the interaction between Ni and Al2O3 and then resulting in bigger Ni particle. Under the same CRM reaction conditions, the as-prepared Ni-0.35C/Al2O3 catalyst without further reduction showed highest catalytic activity and stability. The use of the directly reduced Ni-based catalyst without further high-temperature reduction is promising for the development of a more efficient CRM process.