Nickel Carbon Research Articles

Recent Progress on Cobalt‐Based Heterogeneous Catalysts for Hydrogen Production from Ammonia Borane

AbstractAmmonia borane (NH3BH3, AB) is a quintessential exemplar of chemical hydrogen storage materials and has been widely used in hydrogen evolution. Although expensive metal catalysts (such as Rh, Ru, Pt, Ag, etc.) exhibit high activity in the hydrolysis of ammonia borane, inexpensive metals are more economical. Cobalt (Co), in particular, is not only relatively inexpensive and readily available, but also possesses high activity and selectivity. Compared to other catalysts, cobalt‐based catalysts have better durability and can maintain catalytic activity for a longer period of time, making them favored by researchers. These catalysts demonstrate excellent stability, hydrogen evolution rate, and turn over frequency. This article summarized previous progress in low price metal cobalt‐based catalysts for hydrogen precipitation from ammonia borane, focusing on cobalt‐based catalysts supported on various supports, especially those supported on carbon materials, metal oxides, MOFs, and nickel foams. The characteristics of high‐performance catalytic systems are analyzed in detail. The development prospects of Co catalysts for hydrogen production from ammonia borane were also discussed. In summary, this review compiles various supported and other types of cobalt based catalysts in recent years, and also identifies the existing problems with these catalysts, providing a reference for developers to study these catalysts. It is believed that through careful regulation of the electronic and spatial structures of Co based catalysts, well‐designed Co based non precious metal catalysts will play a significant role in the decomposition of ammonia borane.

A hierarchical host microstructure enables regulated inner Li deposition for stable Li metal electrodes

Dendritic lithium (Li) deposition is a critical issue hindering the development of next-generation high-energy-density Li metal batteries (LMBs). Confining Li deposition within a three-dimensional host is a general strategy to suppress the volume expansion of the Li electrode. However, precise control of continuous Li growth in the pore space of the host is rarely investigated, which is a crucial issue to enable a high utilization ratio of the hosted Li for practical LMBs. Herein, a novel hierarchical host structure possessing a multifunctional secondary porous structure to regulate the continuous Li growth with high uniformity and reversibility is proposed. The secondary porous structure consisting of carbon nanotubes, nickel and Li2O-enriched solid electrolyte interphase is in-situ generated via lithiation reaction of a modified nickel foam scaffold, exhibiting high lithiophilicity, fast Li+ transportation and charge transfer. The LMB utilizing Li metal electrodes hosted by this rational structure achieved a stable cycling over 300 cycles with a practical LiFePO4 positive electrode (~2.5 mAh cm-2) at 0.5C/0.5C in the voltage window of 2.5-4.4 V. This work provides a novel approach to designing the host microstructure for constructing more stable Li metal electrode in practical LMBs.

Multifunctional tri-electrode sensors for the measurement of displacement, force, and infrared irradiation

Abstract Here we described the effect of displacement, force and infrared irradiation on the resistance and impedance of tri-electrode multifunctional sensors. These sensors are based on the gel type composite of carbon nanotubes (CNT), nickel phthalocyanine (NiPc) and edible oil. The channel of this tri-electrodes (field effect transistors) structure is made of CNT-NiPc-oil gel composite using rubbing-in technology. The tri-electrode sensors’ response depends upon the direction of force/displacement and shows an anisotropy. Application of force or displacement from the top causes to decrease resistance and the impedance and vice versa in case of applying force or displacement from the side. The displacement and force sensitivities were up to -273.3 Ω/µm and -46.5 Ω/gf from the top and 480.0 Ω/µm and 3.1 x 102 Ω/gf from the side, respectively, for the sensing ranges 0-150 µm and 0-215 gf. Under the effect of the infrared irradiation from any direction the impedance and the resistance of the sensor reduces. On changing infrared irradiation intensity from 0 to 2500 W/m2 the sensitivities from top and side of the sensor were -37.4 Ωm2/W and -16.5 Ωm2/W, respectively. The investigated sensors may potentially be used as prototypes to develop gel-electronic-based shockproof sensors. The technological achievement in fabricating these devices is the consumption of environmentally friendly materials, particularly edible oil (organic). The edible oil allows to formulate uniform composite gel-films, that may not be comprehended only by ingredients mixing. The fabricated sensors are highly attractive for commercialization.

Lightweight composites derived from carbonized taro stems for microwave energy attenuation and thermal energy storage

A novel strategy has been developed for preparing porous carbon materials derived from taro stems, aimed at enhancing electromagnetic wave (EMW) attenuation and thermal energy storage. The materials were synthesized through the carbonization of taro stems to form a porous carbon structure, subsequently enhanced with polyethylene glycol (PEG) containing carbon nanotubes (CNTs) and nickel (Ni) nanoparticles. By adjusting the carbonization temperature and the loading of CNTs and Ni, the resulting carbon materials exhibited exceptional EMW attenuation performance. Specifically, the PC-800 sample demonstrated a remarkable minimum reflection loss of −61.4 dB across the frequency range of 8.2–11 GHz, with a low density of 0.054 g/cm³. The PC-1200 sample exhibited EMI SE values of 23.6 dB axially and 21.5 dB radially in the X-band, with an ultra-low density of 0.033 g/cm³. Further enhancements were observed in the PC/CNT2 and PC/CNT2-Ni15 composites, achieving EMI SE values of 26.3 dB and 26.8 dB, respectively. Additionally, these composites exhibited effective thermal energy storage and release, as confirmed by heating experiments. This study not only introduces a method for creating absorption-dominated biomass electromagnetic shielding materials but also provides a dual-functional solution for enhancing the performance of electronic devices.

Trophic stoichiometry of macroelements and metals in a terrestrial food web

In order to understand the transfer of macroelements and toxic metals in the terrestrial food web, barn swallows, terrestrial frogs, and insects were collected from farmlands in the Leizhou Peninsula, and analyzed for macroelements carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) and trace metals nickel (Ni), zinc (Zn), selenium (Se), copper (Cu), chromium (Cr), cadmium (Cd), lead (Pb), and mercury (Hg). The multi-element ecological stoichiometry was discussed to trace the food web flow of nutrients and toxicants. The percentage contents of C, N, P, and S were 35.43–59.91%, 6.89–12.11%, 0.49–4.66%, and 0.44–2.19%, respectively. The concentrations of Ni, Zn, Se, Cu, Cr, Cd, Pb, and Hg were 0.163–116 mg/kg, 38.7–227 mg/kg, 0.0453–3.82 mg/kg, 3.11–141 mg/kg, not detected—79.6 mg/kg, 0.0203–0.358 mg/kg, 0.148–4.57 mg/kg, and 0.00159–1.46 mg/kg, respectively. Organisms at high trophic levels had higher contents of N, P, and S, and lower contents of C. Significant correlations were observed between δ15N and ratios of C: N, C: P, C: S, N: P, N: S, and S: P, indicating selective transfer of biogenic elements for predators in the terrestrial food web. Most metals including Ni, Zn, Se, Cu, Cr, Pb, and Hg had biomagnification factors and trophic magnification factors higher than 1, because the whole body of organisms rather than tissues were used. The negative correlations between the detoxification ratios of Se: X (each toxic metal) and metal concentrations suggest potential adverse effect of metals on terrestrial organisms.

The comprehensive understanding of intrinsic contribution of nickel foam as a conductive substrate in water splitting

Using nickel foam as a substrate for an electrocatalyst to report overpotential in a manuscript is a popular method in electrochemical testing or water-splitting i.e., the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). However, use of coated Nickel foam as substrate methodology is, in essence, not reasonable for studying the intrinsic chemistry difference of electrocatalysts. To assess water-splitting devices, Ni-foam is a valid substrate if nanoparticles are grown uniformly; however, when drop-casted ink methodology is used or there is inhomogeneous growth of nanoparticles, it becomes difficult to determine whether a particular electrocatalyst is intrinsically active or not. In order to gain a rational understanding of the electrochemical activity and overpotential findings of a specific catalyst, it is essential to recognize the limitations of Ni-foam in reflecting its intrinsic role in electrocatalytic activity. In this study, the same catalyst was drop-casted on three different substrates, namely glassy carbon electrode (GCE), carbon fiber paper (CFP) and nickel foam (NF). It was observed that electrochemical results, such as overpotential, Tafel slope, turnover frequency, and others, varied significantly between NF and CFP or GCE. Therefore, it is concluded that NF should not be preferred as a conductive substrate during electrochemical testing (ET). On the contrary, other neutral substrates like CFP and GCE should be employed.

Copper dual-doping strategy of porous carbon nanofibers and nickel fluoride nanorods as bi-functional oxygen electrocatalysis for effective zinc-air batteries

Designing and developing efficient, low-cost bi-functional oxygen electrocatalysts is essential for effective zinc-air batteries. In this study, we propose a copper dual-doping strategy, which involves doping both porous carbon nanofibers (PCNFs) and nickel fluoride nanoparticles with copper alone, successfully preparing copper-doped nickel fluoride (NiF2) nanorods and copper nanoparticles co-modified PCNFs (Cu@NiF2/Cu-PCNFs) as an efficient bi-functional oxygen electrocatalyst. When copper is doped into the PCNFs in the form of metallic nanoparticles, the doped elemental copper can improve the electronic conductivity of composite materials to accelerate electron conduction. Meanwhile, the copper doping for NiF2 can significantly promote the transformation of nickel fluoride nanoparticles into nanorod structures, thus increasing the electrochemical active surface area and enhancing mass diffusion. The Cu-doped NiF2 nanorods also possess an optimized electronic structure, including a more negative d-band center, smaller bandgap width and lower reaction energy barrier. Under the synergistic effect of these advantages, the obtained Cu@NiF2/Cu-PCNFs exhibit outstanding bi-functional catalytic performances, with a low overpotential of 0.68 V and a peak power density of 222 mW cm−2 in zinc-air batteries (ZABs) and stable cycling for 800 h. This work proposes a one-step way based on the dual-doping strategy, providing important guidance for designing and developing efficient catalysts with well-designed architectures for high-performance ZABs.

(Digital Presentation) Synergistic Enhancement of Thermoelectric Performance through One-Dimensional Hybrid Nanocomposites: Wrapped Nickel Oxide-Decorated Multi-Walled Carbon Nanotubes with Polypyrrole

Given the drawbacks of organic materials’ thermoelectric (TE) conversion efficiency, an approach has been made in this study to synthesize a hybrid organic-inorganic material based on polypyrrole (PPy), multi-walled carbon nanotubes (MWCNTs) and nickel oxide nanoparticles (NiO). The nanocomposite is formed through three steps: MWCNTs functionalization via diazonium salt grafting of 5-amino-1,2,3-benzene tricarboxylic acid; in situ generation on their surfaces of NiO nanoparticles with a homogenous distribution; the chemical polymerization of pyrrole using methyl orange as templating and dopant to wrap the MWCNTs-(COOH)3-NiO. To explore the structural and physical properties of the fillers and the nanocomposites, X-ray diffraction (XRD), Transmission electron microscopy (TEM), Raman spectrometer, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) were used. Thereby investigating the electrical conductivity (𝜎), Seebeck coefficient (S) and thermal conductivity (κ) at room temperature, a promising improvement was observed in PPy-MWCNTs-(COOH)3-NiO compared to pure PPy. The observed enhancements in TE properties (ZTPPy-MWCNTs-(COOH)3-NiO = 1.51×10-2) are attributed to the presence of NiO, which acts as a dopant and improves the charge carrier density in the nanocomposite; this result could be increased at higher temperatures. Overall, these results demonstrate the potential of our approach for developing high-performance TE materials with applications in energy harvesting and waste heat recovery. Furthermore, this approach offers the potential for scalability and reproducibility, making it a promising method for large-scale fabrication of high-performance composites. Figure 1

Solar H2O2 production with carbon dots and nickel co-modified titania nanotube photocatalyst stabilized at water/benzyl alcohol interface

An interfacial reaction system with the advantage of in situ H2O2 production and separation has been developed, in which titania nanotube (TNT) photocatalyst modified by nickel species and carbon dots (CDs) can self-stabilize at interface of water/benzyl alcohol. Under visible light irradiation, the CDs/Ni-TNT yields H2O2 with an initial rate of 385.6 μmol/g/h. The improved activity could be attributed to multiple effects such as sufficient oxygen adsorption and mass transfer, separated reduction and oxidation sites at different phases, and rapid diffusion of H2O2 from the interfacial region into bulk aqueous solution.

Boosting catalytic performance with bismuth for extended lifespan of light-assisted lithium-oxygen batteries

Photo-assisted Li-O2 batteries have gained significant attention due to their low overpotential. However, the rapid recombination of photogenerated carriers remains a fundamental challenge. Herein, we utilized a one-step hydrothermal method to produce bismuth nanoparticles and loaded bismuth/titanium dioxide/carbon nanotubes onto nickel foam (Bi/TiO2/CNTs/NF) by ultrasonic loading. Bismuth nanoparticles accelerate the transfer of photogenerated electrons and prolong the recombination of photogenerated carriers. As a result, photogenerated carriers act quickly and effectively at the three-phase reaction and interface. Carbon nanotubes (CNTs) and nickel foam (NF) increase the micropores and mesopores of the electrode for oxygen transport and lithium-oxygen storage. Increases the active sites of the electrodes while providing more storage space for the generated lithium peroxide. Accordingly, the photo-assisted Li-O2 battery with Bi/TiO2/CNTs/NF photocathode exhibits excellent multiplicity performance and good reversibility. The charging potential of Bi/TiO2/CNTs/NF was 0.22 V lower than TiO2/CNTs/NF and exhibited excellent cycle stability under illumination (Battery energy efficiency drops by only 6 % after 500 cycles)(Table S1, Supporting Information). This study provides a reference for developing and applying photocatalysts in photo-assisted Li-O2 batteries.

Homologous Temperature Regulated Hierarchical Nanoporous Structures by Dealloying.

Nanoporous metals, fabricated via dealloying, offer versatile applications but are typically limited to unimodal porous structures, which hinders the integration of conflicting pore-size-dependent properties. A strategy is presented that exploits the homologous temperature (TH)-dependent scaling of feature sizes to generate hierarchical porous structures through multistep dealloying at varied TH levels, adjusted by altering dealloying temperatures or the material melting points. This technique facilitates the creation of monolithic architectures of bimodal porous nickel and trimodal porous carbon, each characterized by well-defined, self-similar bicontinuous porosities across distinct length scales. These materials merge extensive surface area with efficient mass transport, showing improved current delivery and rate capabilities as electrodes in electrocatalytic hydrogen production and electrochemical supercapacitors. These results highlight TH as a unifying parameter for precisely tailoring feature sizes of dealloyed nanoporous materials, opening avenues for developing materials with hierarchical structures that enable novel functionalities.

Effects of intercritical annealing time on microstructure, tensile properties, and cryogenic toughness of newly designed ultra-low C low Ni Medium-Mn steel

An ultra-low carbon and low nickel medium manganese heavy steel plates was fabricated by quenching and intercritical annealing process. The effect of annealing time on the tensile properties and impact toughness were studied in relation to the formation of reversed transformation. The results show that excellent mechanical properties with yield strength of 680 MPa, tensile strength of 871 MPa, total elongation of 38.2% and high impact energy of 187 J at −60 °C were obtained. The microstructure comprised of ultra-fine grained ferrite and retained austenite (RA) together with a small amount of martensite after intercritical annealing. Increasing the intercritical annealing time resulted in coarser matrix microstructures, larger and more voluminous retained austenite, but with notably reduced stability. Highly stable RA enhances the work hardening capacity of the steel via sustained deformation-induced transformation (TRIP effect), significantly contributing to the toughening of the multiphase system. In addition, Austenite stability, rather than large-angle grain boundaries and the amount of austenite transformation, is the primary factor determining the low-temperature toughness of medium manganese steel.

Investigating layer-by-layer films of carbon nanotubes and nickel phthalocyanine towards diquat detection

The indiscriminate use of pesticides makes us susceptible to the toxicity of these chemical compounds, which may be present in high quantities in our food. It is crucial to develop inexpensive and rapid methods for determining these pesticides for government control or even for the general population. In this study, we investigated the fabrication of self-assembled LbL films using multi-walled carbon nanotubes (MWCNT) and nickel tetrasulphonated phthalocyanine (NiTsPc) as an electrochemical sensor for the herbicide Diquat (DQ). The Layer-by-Layer (LbL) assembly of the (MWCNT/NiTsPc) film was examined, along with its structural and morphological characteristics. The effect of the number of layers in DQ detection was evaluated by cyclic voltammetry, followed by the detection through differential pulse voltammetry. The achieved limit of detection was 9.62 × 10−7 mol L−1. A ~ 30% decrease in sensitivity was observed in the presence of Paraquat, a banned herbicide and electrochemical interferent due to the structural similarities, which is regularly neglected in the most published studies. The sensor was tested in real samples, demonstrating a recovery of 98.5% in organic apples.

Study on the electrodeposition of MoS2 on different electrode materials used as electrode catalysts for the electrochemical synthesis of ammonia from N2 and H2O

Herein, MoS2 was deposited electrochemically on nickel foam (NF), copper foam (CuF) and carbon paper (CP). The samples were characterized by XRD, SEM and were used as cathodes for the nitrogen reduction reaction in an acidic medium. NH4+ concentration was determined by the indophenol blue method. Both the density of the cathodic current and the NH4+ concentration achieved their highest values with MoS2 deposited on copper foam. However, nickel foam was determined to be a higher-performance electrode material, which showed highest NRR efficiency, 3,62%, probably due to its higher ECSA value.

Construction of an interface interaction in a g-C3N4/CdS/NiS for photoreforming of plastic and clean hydrogen regeneration

Converting plastics into organic matter by photoreforming is an emerging way to deal with plastic pollution and produce valuable organic matter. Water shortage can be alleviated by using seawater resources. To solve these problems, we synthesize a ternary heterostructure composite g-C3N4/CdS/NiS. Heterojunctions are formed between graphitized carbon nitride (g-C3N4), cadmium sulfide (CdS) and nickel sulfide (NiS), which effectively improve the problem of fast charge recombination of pure g-C3N4 and CdS. The results of the g-C3N4/CdS/NiS photocatalytic tests show that the hydrogen production rates in seawater and pure water for 5 h are 30.44 and 25.79 mmol/g/h, respectively. In stability test, the hydrogen production rate of the g-C3N4/CdS/NiS in seawater and pure water is similar. This suggests that seawater can replace pure water as a source of hydrogen. While H2 is generated, the lactate obtained by polylactic acid (PLA) hydrolysis is oxidized to form small organic compounds such as formate, acetate and pyruvate. Our study shows that g-C3N4/CdS/NiS can not only use seawater as a hydrogen source to produce H2, but also photoreformate plastics dissolved in seawater into valuable small organic molecules. This has a positive impact on the production and use of clean energy, as well as on plastic pollution and water scarcity.

The Effect of Modified Material in Screen-Printed Carbon Electrode for Oxalic Acid Detection

In this study, we investigated the effect of modified material on screen-printed carbon electrode (SPCE) for detection of oxalic acid. The SPCE was modified with (1) carbon conductive ink and (2) combination of carbon conductive ink and nickel nanoparticles (Ni-NPs). Modification process of (1) was conducted using drop-cast method by adding a mix of carbon conductive ink and nickel nanoparticles (1:1) on the surface of SPCE. Modified SPCE was then dried and stored in desiccator. Performance test of SPCE with and without modification was carried out using cyclic voltammetry (CV) method. The CV scan was done at the range of-0.5 to 1.5 V with scan rate of 100 mV/s in 20 mM oxalic acid solution. The result showed that carbon conductive ink and nickel nanoparticles mix (1:1) modified SPCE could be used to detect oxalic acid on potential 1.2 V.

Enhancing X-band microwave absorption properties with nickel ferrite and carbon-based composites

The present study focuses on synthesizing a composite material comprising of nickel ferrite and carbon derived from cotton, to exhibit exceptional microwave absorption capabilities over a wide frequency range. By adopting a mechanical alloy method, the microwave-absorbing composite is developed. The microwave absorption characteristics of the developed composites are further unearthly in terms of their permittivity and permeability. Combining magnetic and dielectric phases produces better eddy current loss and polarization, which are primarily responsible for absorption characteristics. The developed composites are cast into rectangular pallets to evaluate microwave absorption characteristics and examined using a vector network analyzer within the 8.2–12.4 GHz frequency range. With a pallet thickness of 2.55 mm, the entire X-band frequency is effectively covered, yielding a remarkable minimum reflection loss of −20.46 dB at 10.01 GHz. The current work's findings, owing to the synergistic combination of nickel ferrite and carbonized carbon provide a practical approach for developing a hybrid material with remarkable electromagnetic performance.

Rhodium-decorated palladium nanocubes supported on Ni(OH)2 nanosheets/C for enhanced ethanol oxidation

This study investigates the improvement of Palladium (Pd)-based nanocatalysts for ethanol oxidation in alkaline solutions, a process often hindered by the poisoning of the catalyst’s surface. We synthesise Pd nanocubes and Rhodium (Rh)-decorated Pd nanocubes, both supported by a composite of nickel hydroxide nanosheets and carbon (Ni(OH)2/C). The developed Pd nanocatalysts possess a nanocubic morphology with smaller sizes compared to Pd/C, alongside additional nanostructures like nanorods X-ray absorption near-edge structure and extended X-ray absorption fine structure analyses suggest that Rh decoration on Pd nanocubes prevents Pd oxidation, with Rh itself being oxidised. The electrocatalytic performance of the Rh/Pd/Ni(OH)2/C hybrid catalyst displays a notable enhancement, attributed to the combined effects of the exposed Pd (100) crystal surfaces, the addition of oxygenated species through the Ni(OH)2 component, and the deliberate addition of Rh. Comparative assessments reveal that this composite surpasses Pd/C and Pd/C nanocubes, achieving specific activities that are approximately 11.6 and 3.5 times greater, respectively. Electrochemical Impedance Spectroscopy data and chronoamperometric studies confirm superior ethanol oxidation efficiency and improved catalytic stability. These findings highlight the utility of Rh/Pd/Ni(OH)2/C nanocubes in direct ethanol fuel cells, providing promising pathways for enhancing fuel cell technologies.

Effects of TiO2 nanoparticles on the dielectric and electromagnetic shielding performance of PVA/POM hybrid nanocomposites

ABSTRACT Metal oxide-infused polymer composites with higher dielectric constants are emerging as compelling solutions for effective Electromagnetic Interference shielding (EMIS) applications. In this work, hybrid polymer blends were made of polyoxy methane (POM) and polyvinyl alcohol (PVA), using the conventional solution casting method. This study investigated the dielectric properties of the polymer blend by adding different concentrations (1 to 4 wt.%) of titanium dioxide (TiO2) nanofillers that are synthesized via combustion technique with egg albumen. It is evident from the crystallite size of the TiO2 nanoparticles that the egg albumen not only acted as a fuel but also acted as a capping agent in preventing the agglomeration of the particles thereby controlling the size. Increased nanofiller decreased the crystallinity of the polymer blend. The composite with 3 wt.% TiO2 exhibits the highest dielectric constant (1385) and electromagnetic shielding effectiveness. Further, the developed hybrid nanocomposites exhibit excellent shielding effectiveness in the frequency range of 8 to 12 GHz. The uniqueness of this study lies in the cost-effective preparation of nanocomposites with a very less concentration of TiO2 nanoparticles. These nanocomposite films could be a potential replacement for films infused with carbon black, multiwalled carbon nanotubes, graphene oxide and nickel oxide nanofillers, etc.

Bidirectional heterojunctions photocatalyst engineered with separated dual reduction sites for hydrogen evolution

Photocatalytic technology is identified as one of the most clean and sustainable routes for hydrogen generation. Nonetheless, inadequate photoinduced carrier separation limits photocatalytic performance. Rationally designing bidirectional heterojunctions that leverage single/two-photon co-excitation pathways and dual reduction sites, thereby inhibiting recombination of the photoinduced carriers and exposing active sites to increase photocatalytic activity. This study proposes bidirectional heterojunctions consisting of 0D carbon dots (CDs) and nickel phthalocyanines co-modified sulfur-doped multivesicular carbon nitride tubes (denoted as 7CDs/SMVCTs/Ni0.5 %). The as-prepared photocatalyst displays a remarkable yield of 16,363.62 μmol g−1 h−1, with a rate 23.2 times that of pristine carbon nitride (denoted as PCN, 704.23 μmol g−1 h−1). The improvement of photocatalytic performance is attributed to the efficient separation and transportation of photoexcited electron-hole pairs induced by the coexistence of single/two-photon excitation pathways and dual reduction sites. The efficient combination of lateral and vertical heterostructures plays an essential role in the photocatalytic process and is exhaustively studied using catalyst rational design and modification technology.