Electronic Metal-support Interactions Research Articles

Ultrasound-assisted synthesis of highly dispersed nickel nanoclusters on MXene for efficient dehydrogenation of hydrazine borane

Hydrazine borane (N2H4BH3), recognized as an excellent hydrogen source, has received widespread attention due to its good chemical stability and superior gravimetric hydrogen storage capacity. However, developing monodispersed and ultrafine noble-metal-free nanocatalysts to enhance hydrogen generation from N2H4BH3 is vital yet challenging. In this work, we proposed an ultrasound-assisted synthesis approach to prepare highly dispersed Ni nanoclusters (NCs, ∼1.9 nm) on Ti3C2Tx MXene. The ultrasound-induced oxygen-containing functional groups on the Ti3C2Tx MXene surface can regulate the size and dispersion of Ni particles. The as-prepared Ni/Ti3C2Tx exerts superior catalytic performance and 100% H2 selectivity toward hydrogen production from the aqueous solution of N2H4BH3. Its turnover frequency (TOF) value reaches 302 h−1 at 323 K, which is 6 times higher than that of Ni/Ti3C2Tx prepared without ultrasound treatment and even exceeds almost all previously reported monometallic noble-metal-free catalysts. The superior catalytic efficiency of Ni/Ti3C2Tx is attributed to the highly dispersed and electron-rich Ni NCs, as well as the electronic metal-support interaction (EMSI) between the Ti3C2Tx MXene support and the Ni NCs. Highly active and affordable catalysts provide an effective approach to boost N2H4BH3 as a promising hydrogen storage material in practical application.

Unraveling the Multifunctional Sites of Ag Single-Atom and Nanoparticles Confined Within Carbon Nitride Nanotubes for Synergistic Photocatalytic Hydrogen Evolution.

The development of novel nano-single-atom-site catalysts with optimized electron configurations and active water adsorption (*H2O) to release hydrogen protons (*H) is paramount for photocatalytic hydrogen evolution (PHE), a multi-step reaction process involving two electrons. In this study, an atom-confinement and thermal reduction strategy is introduced to achieve synergistic Ag single-atoms (Ag1) and nanoparticles (AgNPs) confined within carbon nitride nanotubes (Ag1+NPs-CN) for enhanced photocatalytic hydrogen evolution. Mechanistic investigations reveal that H2O adsorption/dissociation predominantly occurs at Ag1 sites, while AgNPs sites notably facilitate H2 release, indicating the synergistic effect between Ag1 and AgNPs in the H2 evolution reaction. Furthermore, the effective confining of Ag species is beneficial for trapping electrons in highly active reaction regions, while the "electronic metal-support interactions" (EMSIs) of AgNPs and Ag1-C2N sites regulate the d-band centers and effectively optimize the adsorption/desorption of intermediates in photocatalytic hydrogen evolution, leading to enhanced H2 production performance. This work demonstrates the potential of the construction of synergistic photocatalysts for efficient energy conversion and storage; Hydrogen production; Nanoparticles; Photocatalysis; Single atom; and Synergistic effect.

Controlling Metal-Support Interactions to Engineer Highly Active and Stable Catalysts for COx Hydrogenation.

This perspective focuses on the modulation of metal-support interaction (MSI) in catalysts for COx hydrogenation, highlighting their profound impact on catalytic performance. Firstly, it outlines different strategies, including the use of highly reducible oxides and moderate reduction treatments, which induce the classical strong metal-support interaction (SMSI) effect and the electronic metal-support interaction (EMSI) effect. Morphology engineering and crystalline phase manipulation of oxides presented as effective methods to control EMSI are also discussed. The discrimination of SMSI and EMSI can be achieved using oxides with low encapsulation tendencies, such as ZrO2, which supports electronic modifications without or minimizing the overgrowth issues, optimizing the catalytic performance for methanation. Then, the synergy between Cu and ZnO in methanol synthesis, enhanced by SMSI, is emphasized inside. Optimizing support oxides to control oxygen vacancies enhances the catalytic performance of CO2 hydrogenation to methanol. Perspectives for the future research on the fundamental understanding of structure-MSI-performance relationship for catalyst design is discussed.

Engineering MXene Surface via Oxygen Functionalization and Au Nanoparticle Deposition for Enhanced Electrocatalytic Hydrogen Evolution Reaction.

MXene, a family of 2D transition metal carbides and nitrides, presents promising applications in electrocatalysis. Maximizing its large surface area is key to developing efficient non-noble-metal catalysts for the hydrogen evolution reaction (HER). In this study, oxygen-functionalized Ti3C2Tx MXene (Ti3C2Ox) is synthesized and deposited gold nanoparticles (Au NPs) onto it, forming a novel composite material, Au-Ti3C2Ox. By selectively removing other functional groups, mainly -O functional groups are retained on the surface, directing electron transfer from Au NPs to MXene due to electronic metal-support interaction (EMSI), thereby improving the catalytic activity of the MXene surface. Additionally, the interaction between Au NPs and -O functional groups further enhanced the overall catalytic activity, achieving an overpotential of 62 mV and a Tafel slope of 40.1 mV dec-1 at a current density of -10 mA cm-2 in 0.5 m H2SO4 solution. Density functional theory calculations and scanning electrochemical microscopy with ≤150 nm resolution confirmed the enhanced catalytic efficiency due to the specific interaction between Au NPs and Ti3C2Ox. This work provides a surface modification strategy to fully utilize the MXene surface and enhance the overall catalytic activity of MXene-based catalysts.

Electronic Metal‐Support Interaction Induces Hydrogen Spillover and Platinum Utilization in Hydrogen Evolution Reaction

AbstractThe substantial promotion of hydrogen evolution reaction (HER) catalytic performance relies on the breakup of the Sabatier principle, which can be achieved by the alternation of the support and electronic metal support interaction (EMSI) is noticed. Due to the utilization of tungsten disulfides as support for platinum (Pt@WS2), surprisingly, Pt@WS2 demands only 31 mV overpotential to attain 10 mA cm−2 in acidic HER test, corresponding to a 2.5‐fold higher mass activity than benchmarked Pt/C. The pH dependent electrochemical measurements associated with H2‐TPD and in situ Raman spectroscopy indicate a hydrogen spillover involved HER mechanism is confirmed. The WS2 support triggers a higher hydrogen binding strength for Pt leading to the increment in hydrogen concentration at Pt sites proved by upshifted d band center as well as lower Gibbs free energy of hydrogen, favourable for hydrogen spillover. Besides, the WS2 shows a comparably lower effect on Gibbs free energy for different Pt layers (−0.50 eV layer−1) than carbon black (−0.88 eV layer−1) contributing to a better Pt utilization. Also, the theoretical calculation suggests the hydrogen spillover occurs on the 3rd Pt layer in Pt@WS2; moreover, the energy barrier is lowered with increment in hydrogen coverage on Pt. Therefore, the boosted HER activity attributes to the EMSI effect caused hydrogen spillover and enhancement in Pt utilization efficiency.

Electronic Metal-Support Interaction Induces Hydrogen Spillover and Platinum Utilization in Hydrogen Evolution Reaction.

The substantial promotion of hydrogen evolution reaction (HER) catalytic performance relies on the breakup of the Sabatier principle, which can be achieved by the alternation of the support and electronic metal support interaction (EMSI) is noticed. Due to the utilization of tungsten disulfides as support for platinum (Pt@WS2), surprisingly, Pt@WS2 demands only 31 mV overpotential to attain 10 mA cm-2 in acidic HER test, corresponding to a 2.5-fold higher mass activity than benchmarked Pt/C. The pH dependent electrochemical measurements associated with H2-TPD and in situ Raman spectroscopy indicate a hydrogen spillover involved HER mechanism is confirmed. The WS2 support triggers a higher hydrogen binding strength for Pt leading to the increment in hydrogen concentration at Pt sites proved by upshifted d band center as well as lower Gibbs free energy of hydrogen, favourable for hydrogen spillover. Besides, the WS2 shows a comparably lower effect on Gibbs free energy for different Pt layers (-0.50 eV layer-1) than carbon black (-0.88 eV layer-1) contributing to a better Pt utilization. Also, the theoretical calculation suggests the hydrogen spillover occurs on the 3rd Pt layer in Pt@WS2; moreover, the energy barrier is lowered with increment in hydrogen coverage on Pt. Therefore, the boosted HER activity attributes to the EMSI effect caused hydrogen spillover and enhancement in Pt utilization efficiency.

Band gap effect of TiO2 on supported Ru single-atom catalysts for CO2 methanation by DFT calculations

The influence of TiO2 band gap on structure and reactivity of the supported single ruthenium (Ru1) atom was studied by density functional theory calculations, utilizing Ru1/2L-TiO2 and Ru1/3L-TiO2 as model catalysts for CO2 methanation. The supports have band gaps of 2.39 eV and 1.48 eV, respectively. The band gap plays a significant role in electronic metal-support interactions (EMSIs) and the position of the d-band center of the Ru1 on the TiO2. The Ru1/3L-TiO2, the Ru1 catalyst supported on the 3L-TiO2 with a narrower band gap, shows enhanced EMSIs and a d-band center that is positioned farther from Fermi level, leading to lower charge density on the Ru1 and weaker adsorption of H2, CO2, and CO compared to the Ru1/2L-TiO2. CO2 methanation followed CO pathway, with the hydrogenation of CO* to HCO* identified as the rate-determining step on the Ru1/nL-TiO2. The Ru1 catalyst supported on TiO2 with a narrower band gap is more favorable kinetically and thermodynamically for CO2 methanation, despite the band gap not altering the reaction pathway. Enhanced hydrogen mobility and a pronounced promotional effect of hydrogen on CO adsorption, due to the narrower band gap support, are key factors facilitating the easier hydrogenation of CO* on the Ru1/3L-TiO2.

Strong Metal-Support Interaction between Pt and TiO2 over High-temperature CO2 Hydrogenation.

The catalytic activities and stability of oxide-supported metal catalysts are significantly affected by metal-support interactions (MSI) between oxidic supports and supported metals. The surface properties of the support, such as its phase and defects, are crucial in MSI, including both the strong metal-support interaction (SMSI) and electronic metal-support interaction (EMSI). In this study, modulation of SMSI was achieved on rutile-supported Pt nanoparticles (NP) over high-temperature CO2 hydrogenation. The encapsulation of Pt NP surfaces with TiO2-x overlayers is precisely controlled by the defects. It is found that oxygen vacancy defects significantly enhance the catalytic stability of Pt/rutile under high-temperature reverse water-gas shift (RWGS) reaction by inhibiting the occurrence of SMSI. Pt/rutile with oxygen vacancies achieves a 301 molCO×gM-1×h-1 space time yield and considerably catalytic stability (decreased by 8%) at 800 °C over 100 h time-on-stream. Density functional theory (DFT) calculations suggest that the adsorption capacity of Pt NP on the rutile overlayer can be reduced by increasing electron density. Experimental results combined with DFT calculations show that electron transfer from Pt NP to rutile is reduced by the oxygen vacancy defects on Pt/R, preserving the metallic nature of Pt species during CO2 hydrogenation, thereby preventing the formation of SMSI.

Strong Metal‐Support Interaction between Pt and TiO2 over High‐temperature CO2 Hydrogenation

The catalytic activities and stability of oxide‐supported metal catalysts are significantly affected by metal‐support interactions (MSI) between oxidic supports and supported metals. The surface properties of the support, such as its phase and defects, are crucial in MSI, including both the strong metal‐support interaction (SMSI) and electronic metal‐support interaction (EMSI). In this study, modulation of SMSI was achieved on rutile‐supported Pt nanoparticles (NP) over high‐temperature CO2 hydrogenation. The encapsulation of Pt NP surfaces with TiO2−x overlayers is precisely controlled by the defects. It is found that oxygen vacancy defects significantly enhance the catalytic stability of Pt/rutile under high‐temperature reverse water‐gas shift (RWGS) reaction by inhibiting the occurrence of SMSI. Pt/rutile with oxygen vacancies achieves a 301 molCO×gM‐1×h‐1 space time yield and considerably catalytic stability (decreased by 8%) at 800 °C over 100 h time‐on‐stream. Density functional theory (DFT) calculations suggest that the adsorption capacity of Pt NP on the rutile overlayer can be reduced by increasing electron density. Experimental results combined with DFT calculations show that electron transfer from Pt NP to rutile is reduced by the oxygen vacancy defects on Pt/R, preserving the metallic nature of Pt species during CO2 hydrogenation, thereby preventing the formation of SMSI.

Self-Reconstruction Induced Electronic Metal-Support Interaction for Modulated Cu+ Sites on TiO2 Nanofibers in Electrocatalytic Nitrate Conversion.

The Cu+ active sites have gained great attention in electrochemical nitrate reduction, offering a highly promising method for nitrate removal from water bodies. However, challenges arise from the instability of the Cu+ state and microscopic structure over prolonged operation, limiting the selectivity and durability of Cu+-based electrodes. Herein, a self-reconstructed Cu2O/TiO2 nanofibers (Cu2O/TiO2 NFs) catalyst, demonstrating exceptional stability over 50 cycles (12 h per cycle), a high NO3 --N removal rate of 90.2%, and N2 selectivity of 98.7% is reported. The in situ electrochemical reduction contributes to the self-reconstruction of Cu2O/TiO2 nanofibers with stabilized Cu+ sites via the electronic metal-support interaction between TiO2 substrates, as evidenced by in situ characterizations and theoretical simulations. Additionally, density functional theory (DFT) calculations also indicate that the well-retained Cu+ sites enhance catalytic capability by inhibiting the hydrogen evolution reaction and optimizing the binding energy of *NO on the Cu2O/TiO2 NFs heterostructure surface. This work proposes an effective strategy for preserving low-valence-state Cu-based catalysts with high intrinsic activity for nitrate reduction reaction (NO3RR), thereby advancing the prospects for sustainable nitrate remediation technologies.

Highly active ternary Ir/In2O3-ZrO2 catalyst for CO2 hydrogenation towards methanol: The role of zirconia

Indium oxide supported iridium catalyst has been verified to be highly active and selective for CO2 hydrogenation to methanol. In this work, zirconia is introduced into the Ir/In2O3 system as a novel Ir/In2O3-ZrO2 ternary catalyst. The solid solution generated between ZrO2 and In2O3 exhibits a strong electronic metal-support interaction with iridium, rendering the supported iridium species highly dispersed in a form of clusters. Thereout, an active interface between iridium and the solid-solution carrier is thus generated, on which electron transport is more feasible with a stronger CO2 adsorption than that of on the Ir−In2O3 interfacial site. Moreover, compared to Ir/In2O3, this ternary catalyst exhibits better catalytic activity as well as the stability. Density functional theory (DFT) simulations, combined with the in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) studies, further demonstrate the CO-hydrogenation pathway is the most favored for methanol synthesis, providing a rationale for the superior methanol selectivity of the Ir/In2O3-ZrO2 catalyst during CO2 hydrogenation.

Regulating Atomically-Precise Pt Sites for Boosting Light-Driven Dry Reforming of Methane.

Light-driven dry reforming of methane is a promising and mild route to convert two greenhouse gas into valuable syngas. However, developing facile strategy to atomically-precise regulate the active sites and realize balanced and stable syngas production is still challenging. Herein, we developed a spatial confinement approach to precisely control over platinum species on TiO2 surfaces, from single atoms to nanoclusters. The configuration comprising single atoms and sub-nanoclusters engenders pronounced electronic metal-support interactions, with resultant interfacial states prompting surface charge rearrangement. The unique geometric and electronic properties of these atom-cluster assemblies facilitate effective activation of CH4 and CO2, accelerating intermediate coupling and minimizing side reactions. Our catalyst exhibits an outstanding syngas generation rate of 34.41 mol gPt -1 h-1 with superior durability, displaying high apparent quantum yield of 9.1 % at 365 nm and turnover frequency of 1289 h-1. This work provides insightful understanding for exploring more multi-molecule systems at an atomic scale.

Application of catalyst Cu-t-ZrO2 based on the electronic metal-support interaction in electrocatalytic nitrate reduction

A novel Cu-t-ZrO2 catalyst with enhanced electronic metal-support interaction (EMSI) is designed for efficient electrocatalytic conversion of nitrate (NO3−) to ammonia (NH3), achieving a remarkable Faradaic efficiency and yield rate of 97.54% and 33.64 mg h−1 mgcat−1, respectively. Electrons are more likely to be transferred from Cu to t-ZrO2 at the electron-rich interface due to the lower work function, which promotes the formation of highly active Cu species and facilitates NO3− adsorption, ensuring selective conversion into NH3.

Strong electronic metal-support interaction of Ni4Mo/N-SrMoO4 promotes alkaline hydrogen electrocatalysis

Ni4Mo electrocatalyst stands out as the promising candidate for hydrogen evolution/oxidation reaction (HER/HOR), yet the intensive hydrogen adsorption leads to sluggish kinetics, decreasing hydrogen catalysis efficiency. Herein, the structure of Ni4Mo nanoparticles anchored on wafer-biscuit-like N-SrMoO4 nanorods (Ni4Mo/N-SrMoO4) is developed to accelerate reaction kinetics by modulating electronic structure. The designed N-SrMoO4 support enables strong electronic metal-support interaction with Ni4Mo, resulting in a downward shift of d-band center and achieving thermally neutral hydrogen adsorption. Ni4Mo/N-SrMoO4 exhibits HER performance with an ultralow overpotential of 15 mV at 10 mA cm−2, superior to Pt/C (η10=18 mV). The outstanding exchange current density of 10.2 mA cm−2 for HOR is three times higher than that of Pt/C (3.5 mA cm−2). Ni4Mo/N-SrMoO4 is further assembled in anion exchange membrane water electrolyzer (AEMWE), resulting in a current density of 100 mA cm−2 at voltage of 1.71 V and the excellent stability of 300 hours. Theoretical calculations and in-situ spectroscopy indicate that the introduction of Sr in N-SrMoO4 effectively enhances electronic metal-support interaction, facilitates the enrichment of adsorbed hydroxyl (OHads) on active sites and weakens hydrogen adsorption on Ni4Mo, thereby accelerating reaction kinetics of hydrogen electrocatalysis.

WS2 Moiré Superlattices Supporting Au Nanoclusters and Isolated Ru to Boost Hydrogen Production.

Maximizing the catalytic activity of single-atom and nanocluster catalysts through the modulation of the interaction between these components and the corresponding supports is crucial but challenging. Herein, guided by theoretical calculations, a nanoporous bilayer WS2 Moiré superlattices (MSLs) supported Au nanoclusters (NCs) adjacent to Ru single atoms (SAs) (Ru1/Aun-2LWS2) is developed for alkaline hydrogen evolution reaction (HER) for the first time. Theoretical analysis suggests that the induced robust electronic metal-support interaction effect in Ru1/Aun-2LWS2 is prone to promote the charge redistribution among Ru SAs, Au NCs, and WS2 MSLs support, which is beneficial to reduce the energy barrier for water adsorption and thus promoting the subsequent H2 formation. As feedback, the well-designed Ru1/Aun-2LWS2 electrocatalyst exhibits outstanding HER performance with high activity (η10=19mV), low Tafel slope (35mVdec-1), and excellent long-term stability. Further, in situ, experimental studies reveal that the reconstruction of Ru SAs/NCs with S vacancies in Ru1/Aun-2LWS2 structure acts as the main catalytically active center, while high-valence Au NCs are responsible for activating and stabilizing Ru sites to prevent the dissolution and deactivation of active sites. This work offers guidelines for the rational design of high-performance atomic-scale electrocatalysts.

Strong Electronic Metal-Support Interactions Enable the Increased Spin State of Co-N4 Active Sites and Performance for Acidic Oxygen Reduction Reaction.

Nonprecious metal catalysts, particularly M-N-C catalysts, are widely recognized as promising contenders for the oxygen reduction reaction (ORR). However, a notable performance gap persists between M-N-C catalysts and Pt-based catalysts under acidic conditions. In this study, hybrid catalysts comprising single Co atoms and ultralow concentrations of Pt3Co intermetallic nanoparticles (NPs) are introduced to enhance ORR performance. Under acidic conditions, these hybrid catalysts demonstrate ORR efficiency with a half-wave potential of 0.895 V, negligible decay even after 80 000 cycles, and a high maximum power density of 1.34 W cm-2 in fuel cells. This performance surpasses those of Co-N-C and Pt/Co-N-C catalysts. Both experimental findings and theoretical computations suggest that the heightened ORR activity stems from an increase in the spin density of Co sites induced by noble metal NPs, facilitating the activation of O-O bonds via side-on overlapping and enabling a transition in the reaction pathway from associative to dissociative processes. This research offers a promising avenue for the systematic design of M-N-C cathodes with an enhanced performance for acidic fuel cells.

Selective hydrogenation of acetylene over Pd/β-Mo2C catalyst: Experimental and theoretical studies

Molybdenum carbide is a promising support to tune the metal reactivity, which originates from the interaction between metal and support. In this work, Pd/β-Mo2C was prepared using a deposition-precipitation method for selective hydrogenation of acetylene. The high temperature calcination is employed to modulate the interaction between Pd and β-Mo2C. The Pd/β-Mo2C catalyst calcined at 600 °C exhibits significant promotion in selective hydrogenation, which shows 100 % acetylene conversion and 81.4 % ethylene selectivity at 160 °C. The activity promotion originates from the enhanced electronic metal-support interaction, which induces a shift of Pd 3d to higher binding energy. Besides, the Pd species become atomically dispersed after calcination. The changes in geometric and electronic structure suppress the formation of Pd hydrides, which consequently inhibits the excessive hydrogenation capacity of Pd. The structure variation also affects the adsorption of ethylene. No strong adsorbed ethylene (di-σ bonded ethylene) can be identified, which is conducive to the improvement of ethylene selectivity. Density functional theoretical (DFT) calculations confirm that Pd on β-Mo2C is positively charged. The desorption energy of C2H4* (0.78 eV) is significantly lower than that of further hydrogenation (1.45 eV), which explains the improved ethylene selectivity of the calcinated catalyst. The present study indicates calcination is an effective method to tune the activity of Pd/β-Mo2C for reactions beyond selective hydrogenation of acetylene.

Constructing ultralow-loading Cu single atoms/Fe2O3 particles on Nb2C MXenes for efficient utilization of atomic H to boost electrochemical debromination

Bromate is a commonly identified carcinogenic and genotoxic disinfection byproduct in water. Electrochemical debromination is an environmentally friendly and effective approach but it often suffers the limited reducing atomic H (H*) ability and high metal catalyst dosage. In this study, a unique composite catalyst comprised of ultra-low loading Cu single atoms (0.016 wt%) and Fe2O3 nanoparticles supported on a Nb2C MXene (denoted as Cu0.2/Fe0.1/Nb2C) was synthesized by one-step high-temperature molten salt method. The Cu0.2/Fe0.1/Nb2C significantly outperformed the Nb2C, Cu0.2/Nb2C and Fe0.1/Nb2C counterparts in the electrochemical debromination with a 94.2 % removal efficiency of bromate. It is revealed that the introducing of Cu single atoms, efficiently promotes the adsorption of H* and inhibition of competitive H2 evolution. The incorporation of Fe2O3 nanoparticles significantly increased the electronic metal-support interaction effect between the metal components and Nb2C, thereby forming a noticeable electronic cloud bridge to facilitate efficient charge transfer. Ultimately, the synergistic interplay between Cu single atoms and Fe2O3 nanoparticles plays a crucial role in achieving the remarkable removal performance of bromate. This work not only presents a significant instance of a synergistic catalyst involving metal single atoms and metal nanoparticles for effective electrochemical debromination but also advances the understanding of the electronic metal-support interaction.

Support work-function dependent Fenton-like catalytic activity of Co single atoms for selective cobalt(IV)=O generation

In Fenton-like reactions, high-valent cobalt-oxo (CoIV=O) has attracted increasing interests due to high redox potential, long lifetime, and anti-interference properties, but its generation is hindered by the electron repulsion between the electron rich oxo- and cobalt centers. Here, we demonstrate CoIV=O generation from peroxymonosulfate (PMS) activation over cobalt single-atom catalysts (Co-SACs) using in-situ Co K-edge X-ray absorption spectra, and discern that CoIV=O generation is dependent on the support work-function (WF) due to the strong electronic metal-support interaction (EMSI). Supports with a high WF value like anatase-TiO2 facilitate the binding of PMS-terminal oxo-ligand to Co sites by extracting Co-d electrons, thus decreasing the generation barrier for the critical intermediate (Co-OOSO32−). The Co atoms anchored on anatase-TiO2 (Co-TiO2) exhibited enhanced CoIV=O generation and superior activity for sulfamethoxazole (SMX) degradation during PMS activation. The normalized steady-state concentration of CoIV=O in Co-TiO2/PMS system was three orders of magnitude higher than that of free radicals, and 1.3- to 11-fold higher than that generated in other Co-SACs/PMS systems. Co-TiO2/PMS sustained efficient removal of SMX with minimal Co2+ leaching under continuous flow operation, suggesting its attractive water purification potential. Overall, these results underscore the significance of support selection for enhanced generation of high-valent metal-oxo species and efficient PMS activation in supported metal SACs.

Sustainable catalytic pathways for biofuel precursors: quantitative conversion of glucose to gluconic acid using Pt-Zn biochar catalyst

Achieving quantitative conversion of biomass-derived feedstocks under ambient environmental conditions (20°C, atmospheric air, 0.1 MPa) is a critical milestone for sustainability in chemical processes. Herein, the quantitative conversion of glucose to gluconic acid was accomplished under ambient environmental conditions without any additives using a Pt-Zn intermetallic nanoparticle-supported biochar catalyst prepared from raw rice straw (Pt-Zn/strawC) via a straightforward one-pot solvothermal reaction with ethylene glycol solvent. Spectroscopic analyses verified the formation of the Pt-Zn intermetallic alloy and confirmed strong electronic metal-support interactions. The Pt-Zn/strawC catalyst (Pt:Zn molar ratio of 1:6) was highly selective for the conversion of glucose to gluconic acid, whereas yields as high as 99.9% (98.9% gluconic acid, 1.0% glucaric acid) were reached at 20 oC under base-free and additive-free conditions. Isotope measurements and density functional theory revealed synergistic interactions in the Pt-Zn alloy, wherein the alloy tended to absorb glucose and active O2 into superoxide radical (O2·). This work demonstrates a chemocatalytic method that is practical for environmental conditions and provides a new avenue for sustainable conversion of lignocellulosic biomass to chemical products.