EES catalysis最新文献

The electrochemical N₂ reduction reaction (eNRR) is a promising pathway for clean and sustainable production of ammonia, a compound essential for global industry. The challenges of the eNRR lie in the complexity of the electrode–electrolyte interface (EEI). While advances have been made in tuning the electrolyte compositions, the understanding of underlying atomic-level mechanisms remains limited. Operando computational techniques are emerging as instrumental tools to address relevant issues. In this review, we highlight a path forward by summarizing the recent advances in engineering strategies for direct-eNRR, including cations, organic solvents, ionic liquids; and for indirect-NRR with the incorporation of lithium-mediators. Additionally, we summarized relevant computational techniques that can investigate the interfacial dynamic properties associated with electrolyte modifications within N₂ reduction. By promoting the application of these computational methodologies, this review contributes to the ongoing efforts towards the realization of highly efficient electrochemical N₂ reduction.

The sustainable electrocatalytic reduction of carbon dioxide into solar fuels offers a potential pathway to mitigate the impact of greenhouse gas-induced climate change. Here, we successfully achieved a high solar-to-fuel (STF) efficiency of 11.5% by integrating a low-cost tandem solar cell with robust, high-performance, non-precious metal-based electrocatalysts. The bismuth-based cathode exhibited a high formic acid selectivity of 97.2% at a potential of −1.1 V_RHE, along with an outstanding partial current density of 32.5 mA cm⁻². Furthermore, upon undergoing more than 24 hours of electrolysis, we observed an enhancement in the catalytic activity. Through comprehensive analysis including in situ Raman spectroscopy and density functional theory (DFT) calculations, we elucidated that the in situ transformation of bismuth into bismuth subcarbonate (BOC) induces multiple effects: (i) the formation of grain boundaries between phases with distinct lattice parameters, (ii) electronic modulation due to defect formation, and (iii) changes in the binding modes of key reaction intermediates on active sites, resulting in the stabilization of *OCHO species. The cause of these phase transformations was attributed to the structural similarity between the cathode template and BOC. The sustainability of the STF efficiency sets a new benchmark for all cost-effective photovoltaic-coupled electrochemical systems.

The electrocatalytic hydrogen evolution reaction (HER) is an efficient technology for hydrogen production and holds great significance for the development of renewable energy economies. Rare-metal-based catalysts are considered benchmark catalysts for the HER; however, their application in HER reactors is limited due to their high cost and poor stability. Rare-metal single atom catalysts (RMSACs) can be considered as promising candidates for the HER due to several advantages such as high activity, high stability, and high atom utilization. The rational design of RMSACs for HER reactors has become a research hotspot in this field. This paper reviews the research progress in the development of RMSACs for large scale hydrogen production under actual operating conditions, including high current density, seawater electrolysis, and long-term operation. Firstly, the mechanism, design and synthesis method of RMSACs for the HER are summarized. Then the atomic-level rational design strategy of RMSACs was proposed for enhancing the HER performance under actual operating conditions. Lastly, the opportunities and challenges for industrial applications of RMSACs are also discussed.

Methanol (CH₃OH) synthesis from carbon dioxide (CO₂) hydrogenation is an industrially viable approach to CO₂ utilization. For the recently developed indium oxide (In₂O₃) catalyst, higher performance may be achieved by introducing transition metal promoters, although recent studies suggest that single atom sites favour CO formation. Here, by density functional theory-based microkinetic simulations, bulk-doped Pt/In₂O₃ single atom catalysts (SACs) with much higher CO₂ reactivity than the In₂O₃ catalyst while maintaining CH₃OH selectivity were designed. Several Pt/In₂O₃ SACs were synthesized to confirm our theoretical predictions. The synthesized Pt/In₂O₃ SAC in the predominantly bulk-doped form exhibits much higher CO₂ reactivity than the In₂O₃ catalyst with high stability and similar CH₃OH selectivity, yielding a CH₃OH productivity of 1.25 g g_cat⁻¹ h⁻¹. This study demonstrates the power of computational methods in designing oxide-based catalysts for industrial reactions and reveals a bulk-doped SAC with high performance.

Phasing out petrochemical-based thermoplastics with bio-plastics produced in an energy efficient and environmentally friendly way is of paramount interest. Among them, polylactic acid (PLA) is the flagship with its production accounting for 19% of the entire bioplastics industry. Glycerol electrolysis for producing the monomer lactic acid, while co-generating green H₂, represents a promising approach to boost the production of PLA, yet the reaction selectivity has been a bottleneck. Here, we report a combined electrochemical and chemical route using a tandem Pt/C-γ-Al₂O₃ multicomponent catalyst which can achieve a glycerol-to-lactic acid selectivity of 61.3 ± 1.2%, among the highest performance reported so far. Combining an experimental and computational mechanistic analysis, we suggest that tuning the acidic sites on the catalyst surface is crucial for shifting the reaction towards the dehydration pathway, occurring via dihydroxyacetone intermediate. Within the tandem effect, Pt is the active site to electrochemically catalyze glycerol to dihydroxyacetone and glyceraldehyde, while the γ-Al₂O₃ provides the required acidic sites for catalyzing dihydroxyacetone to the pyruvaldehyde intermediate, which will then go through Cannizzaro rearrangement, catalyzed by the OH⁻ ions to form lactic acid. This catalytic synergy improves the selectivity towards lactic acid by nearly two-fold. A selectivity descriptor (ΔG_GLAD* − ΔG_DHA*) from density functional theory calculations was identified, which could be used to screen other materials in further research. Our findings highlight the promise of tandem electrolysis in the development of strategies for selective electrochemical production of high-value commodity chemicals from low value (waste) precursors.

The multi-gram synthesis of a phenylacetylide silver cluster catalyst and its application to the electroreduction of CO₂ to carbon monoxide is described. The procedure involves one synthetic step from commercially available precursors and yields highly crystalline silver acetylide clusters in quantitative yields with no required purification. The crystal structure of the cluster was resolved from the native powder using cutting-edge electron diffraction techniques (3D-ED), and showed to consist of an infinite silver tubular core with radially disposed phenylacetylene ligands. Its catalytic properties were investigated at industry-relevant rates in a flow cell electrolyser. Faradaic efficiencies for CO above 95% were achieved at current densities reaching 350 mA cm⁻². The catalyst's selectivity and stability were shown to be the result of the unique polymeric structure, a result supported by electrochemical characterisation and DFT modelling.

Correction for ‘High photocatalytic yield in the non-oxidative coupling of methane using a Pd–TiO₂ nanomembrane gas flow-through reactor’ by Victor Longo et al., EES. Catal., 2024, 2, 1164–1175, https://doi.org/10.1039/D4EY00112E.

With the continuous development and extensive research of electrocatalytic technology, the unclear dynamic catalytic reaction process limits the in-depth study of reaction regulation mechanisms and the targeted design of excellent catalysts. The comprehension of electrochemical reactions through conventional ex situ characterization techniques poses a formidable challenge. Fortunately, in situ characterization technology makes it possible to further clarify the mechanism of electrocatalytic reactions. Here, we will select some highlight studies of in situ characterization techniques during electrochemical reactions to introduce features and difficulties in practical experiments and give some advice and evaluate future development trends for relevant fields. This article will show the advantages as well as challenges in the in situ technology in electrocatalytic reactions, and indicate the development directions.

Although electrocatalytic reduction of carbon dioxide (CO₂) into chemicals and fuels over Cu-based catalysts has been extensively investigated, the influence of their exposed facets on product selectivity remains elusive. To address this, a series of Cu-based catalysts with different ratios of exposed Cu(100) and Cu(111) facets were synthesized and examined for CO₂ electroreduction, based on which a remarkable interplanar synergistic effect on the selectivity of C₂₊ products was demonstrated. The optimized Cu-based interplanar synergistic catalyst could deliver a faradaic efficiency of 78% with a C₂₊ partial current density of 663 mA cm⁻², which is extremely superior to that of its corresponding Cu counterparts with only the Cu(111) or Cu(100) facet. The interplanar synergistic effect was disclosed using density functional theory calculations to mainly benefit from favorable adsorption and activation of CO₂ into *CO on the Cu(111) facet and significantly promoted C–C coupling on the interface of the Cu(111) and Cu(100) facets, as confirmed by observation of the favorable surface coverage of atop-bound and bridge-bound *CO as well as formation of *OC–CHO intermediates during in situ infrared spectroscopy analysis.

Air plasma catalytic oxidation of toluene (C₇H₈) with the cycled storage-discharge (CSD) mode is a promising technology for toluene (C₇H₈) removal. However, the problem of low CO₂ selectivity must be solved. In this work, a novel HZSM-5 (HZ) supported Au catalyst (Au/HZ) with ca. 5.7 nm Au nanoparticles was prepared by combining impregnation-ammonia washing and plasma treatment, and adopted for C₇H₈ removal. Au/HZ displays a large breakthrough capacity and an excellent oxidation ability of C₇H₈ in dry and wet air plasma. To investigate the mechanism of CO₂ selectivity improvement with the Au/HZ catalyst, air plasma catalytic oxidation of gaseous C₇H₈ and CO, as well as the adsorption of C₇H₈ and CO on the catalysts were conducted. For plasma-catalytic oxidation of gaseous C₇H₈ over Au/HZ, the CO₂ selectivity is 97.5%, significantly higher than those of HZ (55%) and Ag/HZ (62%). In situ TPD tests indicate that Au/HZ possesses a moderate adsorption strength for CO and C₇H₈ compared with HZ and Ag/HZ. Meanwhile, plasma oxidation of CO over Au/HZ reaches 100%, which is much higher than those of HZ (15%) and Ag/HZ (24%). Nearly 100% C₇H₈ conversion and CO₂ selectivity of plasma-catalytic oxidation of C₇H₈ on Au/HZ can be attributed to the moderate adsorption strength of Au/HZ for C₇H₈ and CO, and very high plasma catalytic activity for CO oxidation.