Synthesis of Co-based bimetallic nanocrystals with one-dimensional structure for selective control on syngas conversion

Ba, Rongbin; Zhao, Yue; Yu, Lujing; Song, Jialin; Huang, Shuangshuang; Zhong, Liangshu; Sun, Yuhan; Zhu, Yan

doi:10.1039/c5nr02222c

Cited by 23 publications

(17 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is clear from Figure 3c that the Ni2p 3/2 peak of NiZn-Te-CN-11 shifts negatively by 0.46 eV as compared to that of NiTe 2 -CN, while the Zn2p 3/2 peak of NiZn-Te-CN-11 shifts positively by 0.35 eV as compared to that of ZnTe-CN ( Figure 3c). These results indicate that the electron transfer occurs from ZnTe to NiTe 2 at the interface of the heterostructures, [29,30] which is consistent with the UPS results. Interestingly, the degree of electron transfer in heterostructures with different compositions is also different.…”

Section: Resultssupporting

confidence: 88%

Antiblocking Heterostructure to Accelerate Kinetic Process for Na‐Ion Storage

Sun

Liu

et al. 2020

Small

View full text Add to dashboard Cite

Heterostructures are attracting increasing attention in the field of sodium‐ion batteries. However, it is still unclear whether any two monophase components can be used to construct a high‐performance heterostructure for sodium‐ion batteries, as well as the kind of heterostructures that can boost electrochemical performances. In this study, based on classical semiconductor theories on antiblocking and blocking interfaces, attempts are made to answer the abovementioned queries. For this purpose, NiTe2–ZnTe antiblocking and CoTe2–ZnTe blocking heterostructures are synthesized through a bimetal‐hexamine framework‐derived strategy. The NiTe2–ZnTe antiblocking heterostructure exhibits excellent high‐rate and cycling performances, while the CoTe2–ZnTe blocking heterostructure performs poorly, even compared to their monophase components. Further, kinetic measurements and theoretical calculation confirm that antiblocking heterointerfaces can boost Na‐ion diffusion efficiency and decrease the diffusion barrier, which can be attributed to the highly conductive antiblocking heterointerfaces generated due to electron transfer from NiTe2 to ZnTe. Therefore, this study provides a new perspective to design heterostructures more efficiently, with significantly better Na‐ion storage performance.

show abstract

Section: Resultssupporting

confidence: 88%

Antiblocking Heterostructure to Accelerate Kinetic Process for Na‐Ion Storage

Sun

Liu

et al. 2020

Small

View full text Add to dashboard Cite

show abstract

“…[37] Interestingly, the Ni 2p 3/2 and Ni 2p 1/2 binding energies had lower values when compared with those of nickel metal catalysts, confirming a change in the electronic structure as a result of interactions with the cobalt metal in the NiCo@GC-600 catalyst. [39,40] The O 1s spectrum in Figure S4b features three peaks at 529.3, 531.2, and 532.8 eV, corresponding to surface defects and various functional groups (OH/O) interacting with the metals and the carbon matrix, respectively. [39,40] The O 1s spectrum in Figure S4b features three peaks at 529.3, 531.2, and 532.8 eV, corresponding to surface defects and various functional groups (OH/O) interacting with the metals and the carbon matrix, respectively.…”

Section: Resultsmentioning

confidence: 99%

Graphitic Carbon‐NiCo Nanostructures as Efficient Non‐Precious‐Metal Electrocatalysts for the Oxygen Reduction Reaction

Sivanantham

Shanmugam

2018

ChemElectroChem

View full text Add to dashboard Cite

Composites of graphitic carbon layers and transition metals or metal alloys have received considerable attention for use as non-precious-metal catalysts for ecofriendly energy devices. In this paper, we report graphitic carbon-supported NiCo alloys (NiCo@GC) that function as non-precious-metal electrocatalysts for the oxygen reduction reaction under alkaline conditions. In particular, we examined the effect of the pyrolysis temperature on the oxygen reduction activity. The catalyst prepared at 600 8C provided an oxygen reduction half-wave potential (E 1/2 ) of 0.81 V -only 10 mV less than that of a commercial Pt/C catalyst (0.82 V) -with the transfer of almost four electrons. Structural and chemical studies indicated that the excellent activity and stability of the NiCo@GC catalysts resulted from the strong interactions between (and the combined effects of) the metal and the carbon, dictated by the annealing temperature.

show abstract

“…The Co 2p, Ni 2p, and O 1s X‐ray photoelectron spectrescopy (XPS) spectra of the 3DDP‐Co 3 O 4 , 3DDP‐NCO, and Ni/3DDP‐Co 3 O 4 samples before and after reduction are illustrated in Figure and Figure S6 in the Supporting Information. The Co 2p spectra (Figure a) of the fresh catalysts can be deconvoluted into two spin–orbit doublets assigned to the surface Co 2+ (binding energy (BE) = 781 eV) species at the octahedral sites and the Co 3+ (BE = 779 eV) species at the tetrahedral sites and one or two shake‐up satellite peaks of Co 2+ (BE = 786 eV) . A shift from Co 3+ to Co 2+ occurs during the reduction, and a new peak at a lower BE of 778 eV, due to surface Co 0 species, appears.…”

Section: Methodsmentioning

confidence: 99%

“…The Co 2p spectra (Figure 3a) of the fresh catalysts can be deconvoluted into two spin-orbit doublets assigned to the surface Co 2+ (binding energy (BE) = 781 eV) species at the octahedral sites and the Co 3+ (BE = 779 eV) species at the tetrahedral sites and one or two shake-up satellite peaks of Co 2+ (BE = 786 eV). [10,11] A shift from Co 3+ to Co 2+ occurs during the reduction, and a new peak at a lower BE of 778 eV, due to surface Co 0 species, appears. It is obvious that the Co 0 amount in the reduced 3DDP-NCO sample (3DDP-NCO-R) is much lower than for the 3DDP-Co 3 O 4 and Ni/3DDP-Co 3 O 4 samples, indicating the incomplete reduction of Co in the Ni-Co spinel structure, which may arise from a strong interaction between the Ni and Co. A similar scenario occurs for the Ni 2p ( Figure S6a, Supporting Information) whereby Ni is more readily reduced in the Ni/3DDP-Co 3 O 4 than in the spinel structure (3DDP-NCO-R).…”

mentioning

confidence: 99%

Hierarchically Porous Network‐Like Ni/Co₃O₄: Noble Metal‐Free Catalysts for Carbon Dioxide Methanation

Wang

Arandiyan

Scott

et al. 2018

Advanced Sustainable Systems

View full text Add to dashboard Cite

under relatively mild operating conditions, however, their high cost as well as limited availability restricts their practical application. As an alternative, Ni-and Cobased catalysts are active for CO 2 methanation, [8] although only at a temperature higher than 300 °C, which is unattractive in terms of catalyst stability and increased energy consumption. [9] For this reason, the rational design of a low-cost transition metal catalyst that exhibits high activity and selectivity for CO 2 methanation is highly sought after.Herein, we describe the rational design of cheap energy materials that convert CO 2 directly to methane at low temperature: the efficient Ni/3D draped porous Co 3 O 4 catalyst (denoted as Ni/3DDP-Co 3 O 4 ) for CO 2 methanation, which possesses a high surface area that is rich in surface defects. Catalytic Ni clusters and nanodeposits are uniformly dispersed across the surface of the 3DDP-Co 3 O 4 support. The strong electronic Ni-Co interaction induced by H 2 -reduction and invoked by electron transfer from the Ni to the 3DDP-Co 3 O 4 support (charge-compensating effect), encourages surface oxygen vacancy (V o ) formation, which contributes to the enhanced catalytic activity and selectivity (Scheme 1). To probe the role of Ni within the spinel, the same amount of Ni (12 wt%) was incorporated into the 3DDP-Co 3 O 4 lattice to generate a Ni 0.5 Co 2.5 O 4 (3DDP-NCO) spinel structure. The 3DDP-NCO exhibited poor CH 4 selectivity with a depressed reaction rate due to its lower V o presence. Moreover, the Ni-Co interaction was found to occur within the 3DDP-NCO catalyst during the actual Ni-Co spinel formation process as opposed to during the H 2 reduction step. The strong Ni-Co interaction induced during 3DDP-NCO formation restricts Ni and Co reduction, leading to a poor catalytic performance. In contrast, the Ni/3DDP-Co 3 O 4 , which possessed a richness in V o , good low-temperature reducibility, ideal Ni-Co interaction, and high surface area, provided an increased reaction rate and lower apparent activation energy in conjunction with a 100% CH 4 selectivity.Ni/3DDP-Co 3 O 4 catalysts with a hierarchical porosity were prepared using self-assembled monodisperse poly(methyl methacrylate) (PMMA) microspheres as a template. The 3DDP-Co 3 O 4 structure was obtained by infiltrating a Co nitrate precursor within the interstitial voids of the well-aligned PMMA microspheres, followed by thermal removal of the template. The Ni/3DDP-Co 3 O 4 was synthesized by wet impregnation of the 3DDP-Co 3 O 4 structure with a nickel nitrate solution The impasse always present regarding catalysts for energy conversion reactions is that noble metals with promising activity are limited by their high price and scarcity, whereas base metals with a lower price show moderate activity performance. Herein, a purely transition metal-based, Ni-promoted 3D draped porous Co 3 O 4 (Ni/3DDP-Co 3 O 4 ) catalyst is demonstrated to be highly effective for CO 2 methanation, achieving 100% CO 2 conversion and CH 4 selectivity at 250 °C a...

show abstract

Synthesis of Co-based bimetallic nanocrystals with one-dimensional structure for selective control on syngas conversion

Cited by 23 publications

References 26 publications

Antiblocking Heterostructure to Accelerate Kinetic Process for Na‐Ion Storage

Antiblocking Heterostructure to Accelerate Kinetic Process for Na‐Ion Storage

Graphitic Carbon‐NiCo Nanostructures as Efficient Non‐Precious‐Metal Electrocatalysts for the Oxygen Reduction Reaction

Hierarchically Porous Network‐Like Ni/Co₃O₄: Noble Metal‐Free Catalysts for Carbon Dioxide Methanation

Contact Info

Product

Resources

About

Synthesis of Co-based bimetallic nanocrystals with one-dimensional structure for selective control on syngas conversion

Cited by 23 publications

References 26 publications

Antiblocking Heterostructure to Accelerate Kinetic Process for Na‐Ion Storage

Antiblocking Heterostructure to Accelerate Kinetic Process for Na‐Ion Storage

Graphitic Carbon‐NiCo Nanostructures as Efficient Non‐Precious‐Metal Electrocatalysts for the Oxygen Reduction Reaction

Hierarchically Porous Network‐Like Ni/Co3O4: Noble Metal‐Free Catalysts for Carbon Dioxide Methanation

Contact Info

Product

Resources

About

Hierarchically Porous Network‐Like Ni/Co₃O₄: Noble Metal‐Free Catalysts for Carbon Dioxide Methanation