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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. [ABSTRACT FROM AUTHOR]

Water electrolysis in alkaline media, demonstrating robust facility and cheap electrolyzer construction, are regarded as a promising strategy for industrial green hydrogen generation. Exploring effective alkaline hydrogen evolution electrocatalysts is remained an obstacle to date, which requires additional effort to obtain active hydrogen by water dissociation and promote the following unfavorable hydrogen coupling for further H2 release. Herein, the MoO2 supported RuNi nanoparticle (RuNi‐MoO2) is constructed as an efficient electrocatalyst for hydrogen evolution. Experimental and theoretical analysis demonstrate that the optimized built‐in electric field at the interface between MoO2 and RuNi alloy simultaneously accelerates the water dissociation kinetics and hydrogen spillover. It attains the current densities of 10 and 100 mA cm−2 at ultralow potential of −0.019 and −0.086 V versus RHE, respectively, along with rapid water cleavage kinetics, which even surpasses the commercial Pt/C. The constructing anion exchange membrane water electrolyzer adopting the RuNi‐MoO2 as a cathode electrocatalyst attains an industrial current density of 1 A cm−2 at a low voltage of 1.71 V and steadily operates over 1000 h with a large current density over 1 A cm−2. [ABSTRACT FROM AUTHOR]

Selective electrocatalytic hydrogenation (ECH) of phenol is a sustainable route to produce cyclohexanone, an industrially important feedstock for polymer synthesis. However, attaining high selectivity and faradaic efficiency (FE) for cyclohexanone remain challenging, owning to over‐hydrogenation of phenol to cyclohexanol and competition of hydrogen evolution reaction (HER). Herein, by employing hydrogen spillover effect, we modulate adsorbed hydrogen species (Hads) coverage on Pt surface via migration to TiO2 in an anatase TiO2‐supported Pt catalyst. In ECH of phenol, a high selectivity (94 %) and good FE (63 %) for cyclohexanone are obtained, showing more advantageous performance compared with previous reports. Cyclic voltammetry (CV) tests and electrochemical Raman spectroscopy reveal that Hads migrated from Pt to TiO2. We propose that TiO2‐induced hydrogen spillover contributes to low Hads coverage over Pt, which effectively hinders over‐hydrogenation of cyclohexanone and HER. We establish a scaling relationship between the intensity of hydrogen spillover and cyclohexanone selectivity by varying the types of anatase TiO2, and show the universality of the strategy over other reducible metal oxides as the support (rutile TiO2, CeO2 and WO3). This work showcases an effective strategy for tuning hydrogenation selectivity in electro‐catalysis, by taking advantage of thermo‐catalytically well‐documented hydrogen spillover effect. [ABSTRACT FROM AUTHOR]

The electrosynthesis of multi‐carbon (C2+) alcohols, specifically ethanol and n‐propanol through CO electroreduction (CORR) in H2O, presents a sustainable pathway for intermittent renewable energy storage and a low‐carbon economy. However, achieving high selectivity for alcohol production at industrial current densities is kinetically hampered by side reactions such as ethylene generation and hydrogen evolution reaction, which result from competing adsorption of *CO and *H. In this study, we developed a Cu/Zn alloy catalyst to simultaneously enhance the activity and selectivity for alcohol production by increasing CO capture capacity and enriching active hydrogen on Cu sites. Our findings demonstrate that the Cu/5Zn alloy with a molar ratio of Cu to Zn of 95 : 5 exhibits a Faradaic efficiency of 50 % for the selective electrosynthesis of C2+ alcohols during ampere‐level CO electrolysis. Mechanistic investigations revealed that the Cu/Zn alloy promotes polarized Cu sites, enhancing CO adsorption while facilitating the spillover of hydrogen atoms from Zn to Cu sites, contributing to selective alcohol formation. [ABSTRACT FROM AUTHOR]

Constructing nonmetal promoter‐decorated Pt‐based catalysts is a promising strategy for enhancing selective hydrogenation performance. In this study, a set of carbon dots (CDs)‐modified Pt/SBA‐15 nanocatalysts were synthesized using atomic layer deposition (ALD) and impregnation techniques. The catalysts were characterized using various techniques, including TEM, ICP‐MS, N2 adsorption–desorption isotherms, XRD, XPS, H2−TPD, H–D exchange, CO‐DRIFTS, and so forth. The catalytic performance of the CDs‐Pt/SBA‐15 catalysts was evaluated by the selective hydrogenation reaction of cinnamaldehyde (CAL) to cinnamyl alcohol (COL). The results indicate that there is electron transfer between the CDs and Pt, and the addition of CDs can improve the hydrogen spillover effect, both of which significantly influence the selective catalytic hydrogenation performance of the CDs‐Pt/SBA‐15 catalysts. Among the tested catalysts, 0.44CDs‐Pt/SBA‐15 demonstrated the highest catalytic performance, with conversion and selectivity 2.8 times and 2.2 times higher, respectively, than Pt/SBA‐15. This study provides a new perspective on designing and preparing highly efficient nonmetallic promoter‐modified Pt‐based nanocatalysts and has significant implications for their application in catalytic reactions. [ABSTRACT FROM AUTHOR]

In the pursuit of utilizing renewable energy sources for green hydrogen (H2) production, alkaline water electrolysis has emerged as a key technology. To improve the reaction rates of overall water electrolysis and simplify electrode manufacturing, development of bifunctional electrocatalysts is of great relevance. Herein, CoPBO/Co3O4 is reported as a binary composite catalyst comprising amorphous (CoPBO) and crystalline (Co3O4) phases as a high‐performing bifunctional electrocatalyst for alkaline water electrolysis. Owing to the peculiar properties of CoPBO and Co3O4, such as complementing Gibbs free energy values for H‐adsorption (ΔGH) and relatively smaller difference in their work functions (ΔΦ), the composite exhibits H2 spillover (HS) mechanism to facilitate the hydrogen evolution reaction (HER). The outcome is manifested in the form of a low HER overpotential of 65 mV (at 10 mA cm−2). Moreover, an abundant amount of surface oxygen vacancies (Ov) are observed in the same CoPBO/Co3O4 composite that facilitates oxygen evolution reaction (OER) as well, leading to a mere 270 mV OER overpotential (at 10 mA cm−2). The present work showcases the possibilities to strategically design non‐noble composite catalysts that combine the advantages of HS phenomenon as well as Ov to achieve new record performances in alkaline water electrolysis. [ABSTRACT FROM AUTHOR]

Developing efficient electrocatalyst in sulfides for hydrogen evolution reaction (HER) still poses challenges due to the lack of understanding the role of sulfide heterointerface. Here, we report a sulfide heterostructure RuSx/NbS2, which is composed of 3R‐type NbS2 loaded by amorphous RuSx nanoparticles with S−S bonds formed at the interface. As HER electrocatalyst, the RuSx/NbS2 shows remarkable low overpotential of 38 mV to drive a current density of 10 mA cm−2 in acid, and also low Tafel slope of 51.05 mV dec−1. The intrinsic activity of RuSx/NbS2 is much higher than that of Ru/NbS2 reference as well as the commercial Pt/C. Both experiments and theoretical calculations unveil a reversed charge transfer at the interface from NbS2 to RuSx that driven by the formation of S−S bonds, resulting in electron‐rich Ru configuration for strong hydrogen adsorption. Meanwhile, electronic redistribution induced by the sulfide heterostructure facilitates hydrogen spillover (HSo) effect in this system, leading to accelerated hydrogen desorption at the basal plane of NbS2. This study provides an effective S−S bond strategy in sulfide heterostructure to synergistically modulate the charge transfer and adsorption thermodynamics, which is very valuable for the development of efficient electrocatalysts in practical applications. [ABSTRACT FROM AUTHOR]

Alkaline water splitting has shown great potential for industrial‐scale hydrogen production. However, its broad application is constrained by hydrogen evolution reaction (HER) electrocatalysts, which struggle to achieve optimal current density at low overpotential. The utilization of the hydrogen spillover effect to augment the performance of HER represents a burgeoning area of research. Although previous studies mainly focused on hydrogen spillover in acidic media, the latest studies have shown that hydrogen spillover also exists under alkaline conditions, and its role in improving HER performance cannot be ignored. This review examines the mechanisms of HER under acidic and alkaline conditions, elucidating the distinctive behavior of hydrogen spillover in these environments and its influence on catalytic processes. At the same time hydrogen spillover characterization methods are systematically summarized, these technologies for understanding and control of hydrogen release process provides strong support. Finally, the recent electrocatalysts that enhance the catalytic performance of alkaline HER by hydrogen spillover effect are comprehensively sorted out and summarized. This review not only demonstrate the practical value of hydrogen spillover under alkaline conditions, but also provide new directions for future design and optimization of electrocatalysts. [ABSTRACT FROM AUTHOR]

The reverse water‐gas shift (RWGS) reaction serves as a critical pathway for converting CO2 into diverse chemicals. The Mars–van Krevelen (MvK) mechanism, which leverages lattice oxygen as the oxidant and oxygen vacancies as reductants, offers an alternative catalytic strategy for the selective RWGS reaction. While Mn‐substituted SrTiO3 (i. e., SrTi0.8Mn0.2O3) has been shown to promote the RWGS reaction selectively via the MvK mechanism, achieving a sufficient conversion of CO2 necessitates elevated temperatures. This study investigated the effect of Pd‐loaded SrTi0.8Mn0.2O3 on the activation of adsorbed H2 molecules, which generated oxygen vacancies and enhanced CO2 conversion. Notably, 1.0 wt % Pd‐loaded SrTi0.8Mn0.2O3 yielded 13.4 % of CO at 673 K, whereas pristine SrTi0.8Mn0.2O3 and Pd‐loaded SrTiO3 yielded negligible or minimal amount of CO. Hydrogen temperature‐programmed reduction and X‐ray absorption spectroscopy measurements revealed that Pd promoted the formation of oxygen vacancies via both thermodynamic and kinetic mechanisms. Fourier transform infrared spectroscopy and kinetic studies revealed that the RWGS reaction over Pd‐loaded SrTi0.8Mn0.2O3 proceeded primarily via the MvK mechanism with a partial contribution from the Langmuir–Hinshelwood mechanism. This study underscores the effectiveness of combining metal and MvK‐type catalysts to enhance the efficiency of the RWGS reaction. [ABSTRACT FROM AUTHOR]

Membrane‐based gas separation offers notable energy efficiency benefits for hydrogen purification, yet it is often hindered by the inherent trade‐off between permeability and selectivity. To address this challenge, a novel mixed matrix membrane (MMM) design is presented to boost H2 separation performance via continuous hydrogen spillover mechanisms for the first time. The MMM incorporates a palladium‐functionalized ZIF‐67 gel (Pd@ZIF‐67 gel) network into a polymer of intrinsic microporosity (PIM‐1) matrix. The ZIF‐67 gel network serves as a uniform dispersion medium for palladium nanoparticles (Pd NPs), thereby generating a multitude of active sites. These exposed sites, in conjunction with the microporous structure of ZIF‐67, facilitate hydrogen dissociation and establish a continuous hydrogen spillover pathway throughout the membrane. This synergistic MMM design leads to substantial improvements in both hydrogen transport and selectivity. At an optimal loading of 28 wt% Pd@ZIF‐67 gel, the MMMs exhibit a H2 permeability of 3620 Barrer and a remarkable 417% enhancement in H2/CH4 selectivity (24.9), surpassing the 2008 upper bound. This approach paves the way for the development of advanced materials tailored for gas separation applications. [ABSTRACT FROM AUTHOR]

The conversion of CO2 into formate through electrochemical methods is emerging as an elegant approach for industrial‐scale CO2 utilization in the near future. Although Bismuth (Bi)‐based materials have shown promise thank to their excellent selectivity, their limited reactivity remains a challenge. Herein, this study demonstrates a significant enhancement in the CO2‐to‐formate efficiency of Bi by incorporating ruthenium (Ru) atomic species. Ru single atom doped Bi exhibited a nearly twofold higher partial current density compared with pure Bi and Ru clusters doped Bi, while over 95% Faradaic efficiency (FE) is maintained. Through comprehensive investigations using a combined approach of electrochemical techniques, operando spectroscopy, and theoretical calculations, this study elucidates that the presence of Ru single atom promotes H2O dissociation and H* migration to Bi sites for CO2‐to‐formate conversion by significantly reducing the energy barrier via a H* spillover path. Besides, it is constructed Ru–Bi bridge sites for efficient CO2 hydrogenation via a non‐spillover path, which served as the major mechanism for CO2‐to‐formate conversion in Ru single atom doped Bi. [ABSTRACT FROM AUTHOR]

Herein, a heterogeneous structure of Ni–Mo catalyst comprising Ni4Mo nanoalloys decorated on a MoOx matrix via electrodeposition is introduced. This catalyst exhibits remarkable hydrogen evolution reaction (HER) activity across a range of pH conditions. The heterogeneous Ni–Mo catalyst showed low overpotentials only of 24 and 86, 21 and 60, and 37 and 168 mV to produce a current density of 10 and 100 mA cm−2 (η10 and η100) in alkaline, acidic, and neutral media, respectively, which represents one of the most active catalysts for the HER. The enhanced activity is attributed to the hydrogen spillover effect, where hydrogen atoms migrate between the Ni4Mo alloys and the MoOx matrix, forming hydrogen molybdenum bronze as additional active sites. Additionally, the Ni4Mo facilitated the water dissociation process, which helps the Volmer step in the alkaline/neutral HER. Through electrochemical analysis, in situ Raman spectroscopy, and density functional theory calculations, the fast HER mechanism is elucidated. [ABSTRACT FROM AUTHOR]

The development of efficient and durable bifunctional electrocatalysts is essential for hydrogen production from acidic water splitting. Herein, a TiO2 nanotube‐loaded Co‐doped Ru nanoparticle catalyst (RuCo/TiO2 NTs) is reported that exhibits excellent activity and stability toward acidic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The Ru─O─Ti bonding is enhanced by Co doping, and the metal carrier interaction between Ru nanoparticles and TiO2 NTs is enhanced, which effectively stabilizes Ru species during OER and initiates hydrogen spillover accelerating HER kinetics. As a result, RuCo/TiO2 NTs catalyst requires only 156 mV OER overpotential and 17 mV HER overpotential to achieve a current density of 10 mA cm−2 with a stability more than 500 h in acidic conditions. More importantly, benefiting from the excellent bifunctional activities, the proton exchange membrane electrolyte assembled from RuCo/TiO2 NTs has excellent activity and robust stability (1000 h). This work opens a new avenue for the efficient energy conversion devices. [ABSTRACT FROM AUTHOR]

The hydrogen spillover mechanism of metal‐supported electrocatalyst can significantly improve HER activity. However, the rational design of binary heterojunction hydrogen spillover electrocatalysts remains a challenge. Here, a NiSe2‐Ni5P4 heterojunction electrocatalyst with superaerophobic structure is synthesized by using a simple substrate self‐derived strategy. Experimental characterization and theoretical calculation reveal the hydrogen spillover mechanism of NiSe2‐Ni5P4 heterogeneous electrocatalyst. NiSe2 and Ni5P4 synergistically promote the adsorption/dissociation of H2O and the adsorption of H*, respectively. The smaller ΔΦ effectively reduced the electron density at the interface, weakening the proton adsorption at the interface and promoting the migration of H* from NiSe2 to Ni5P4. The NiSe2‐Ni5P4 exhibits excellent HER activity in alkaline electrolyte, requiring only a potential of 65, 270 mV to achieve a current density of 10, 500 mA cm−2, respectively, and a stability of up to 200 h. Moreover, the design of NiSe2‐Ni5P4 with superaerophobic structure can reduce the deposition of impurity ions on the electrode surface and avoid Cl− corrosion of the electrode, which results in NiSe2‐Ni5P4 showing better HER activity and stability than commercial Pt/C in brackish water. This study deepens the understanding of hydrogen spillover mechanism of binary heterojunction electrocatalysts, broadens the application of hydrogen production in complex water quality. [ABSTRACT FROM AUTHOR]

Hydrogen spillover in metal‐supported catalysts can largely enhance electrocatalytic hydrogenation performance and reduce energy consumption. However, its fundamental mechanism, especially at the metal–metal interface, remains further explored, impeding relevant catalyst design. Here, we theoretically profile that a large free energy difference in hydrogen adsorption on two different metals (|ΔGH‐metal(i)−ΔGH‐metal(ii)|) induces a high kinetic barrier to hydrogen spillover between the metals. Minimizing the difference in their d‐band centers (Δϵd) should reduce |ΔGH‐metal(i)−ΔGH‐metal(ii)|, lowering the kinetic barrier to hydrogen spillover for improved electrocatalytic hydrogenation. We demonstrated this concept using copper‐supported ruthenium–platinum alloys with the smallest Δϵd, which delivered record high electrocatalytic nitrate hydrogenation performance, with ammonia production rate of 3.45±0.12 mmol h−1 cm−2 and Faraday efficiency of 99.8±0.2 %, at low energy consumption of 21.4 kWh kgamm−1. Using these catalysts, we further achieve continuous ammonia and formic acid production with a record high‐profit space. [ABSTRACT FROM AUTHOR]

Developing an efficient strategy to replace the conventional synthesis method for producing isoindolinone (IIO) scaffold, a crucial structural motif for constructing pharmaceutical molecules, remains to be a great challenge. Herein, a single‐atom Pd/TiO2 tandem catalysis has been developed for the IIO scaffold synthesis by using readily available phthalic anhydride (PA), ammonia, and H2. The single‐atom Pd/TiO2 catalyst demonstrates superior catalytic performance, achieving a PA conversion of 99 %, an IIO selectivity of 91 %, and a turnover frequency (TOF) up to 4807 h−1. This exceptional performance can be attributed to the tandem catalysis between TiO2 support and single‐atom Pd. The TiO2 efficiently catalyzes the conversion of PA with ammonia to form phthalimide (PAM), subsequently transformed into IIO over TiO2 through the reaction of PAM with NH3 and the spillover hydrogen species derived from single‐atom Pd. Notably, NH3 functions not only as a reactant but also as a promoter to accelerate the reduction of amides combined with the Pd/TiO2 catalyst. This tandem catalysis of a single‐atom Pd/TiO2 catalyst provides a promising strategy for the synthesis of the crucial IIO platform molecules. [ABSTRACT FROM AUTHOR]

Pt automatically adsorbed on oxygen vacancy of TiO2 via an in situ interfacial redox reaction, resulting in atomically dispersion of Pt on TiO2. In the upgrading of lignin‐derived 4‐propylguaiacol, single‐atom catalyst (SAC) Pt/TiO2−H achieved a conversion of 96.9 % and a demethoxylation selectivity of 93.3 % under 3 MPa H2 at 250 °C for 3 h, markedly different from the performance of nanoparticle counterpart that gave deep deoxygenation selectivity over 99.0 %. The high demethoxylation activity of SAC Pt/TiO2−H is mainly attributed to its weak hydrogen spillover capacity that suppressed the benzene ring hydrogenation and the deep deoxygenation. Additionally, SAC Pt/TiO2−H reduced the energy barrier of CAr−OCH3 bond cleavage and accordingly lowered the Gibbs free energy of the demethoxylation reaction. This facile method could fabricate single‐atom Au, Pd, Ir, and Ru supported on TiO2−H, demonstrating the generality of this strategy for the establishment of a library of SACs. Moreover, SAC exhibited versatile capacity in demethoxylation of different lignin‐derived monomers and high stability. This study showcases the superiority of atomically dispersed metal catalysts for selective demethoxylation reactions and proposes a renewable alternative to fossil‐based 4‐alkylphenols through upgrading of lignin‐derived monomers. [ABSTRACT FROM AUTHOR]

Interparticle hydrogen spillover is the phenomenon of H migration over different catalyst particles, which should be a physical mixture of at least two solid catalysts. In this review, we analyze examples of enhanced catalysis based on interparticle (reverse) hydrogen spillover. Simple physical mixtures of powdered catalysts containing metal catalysts of H2 dissociation/recombination and solid catalysts with active sites for substrate activation significantly enhance catalytic reactions. These reactions include aromatic hydrogenation, CO2 methanation, and the deoxydehydration of polyols, aromatization of lower paraffins, and direct coupling of benzene and alkanes. The acceleration effect and proposed reaction pathway of each example involving interparticle (reverse) hydrogen spillover are summarized. Simple reaction systems comprising physical mixtures of at least two powdery solid catalysts should enable unique catalysis in the future with the aid of interparticle (reverse) hydrogen spillover. [ABSTRACT FROM AUTHOR]

The effectuation of pH‐universal electrocatalysis is highly attractive but still challenging for the hydrogen evolution reaction (HER). It appeals for not only the facilitated electron transport but also the kinetical proton mass transfer. In this study, a via‐hole Ru/MoO2 confined heterostructure is profiled as a metal‐support platform for the electron/mass transfer‐boosted pH‐universal HER studies. It is indicated that the as‐formed Ru─O─Mo bridge can modulate the electronic transport at the interface, and the proton adsorption and transfer are kinetically derived by the intensified metallic Ru─Ru bond. Resultantly, the Ru/MoO2 heterostructure stably attains the Pt‐beyond HER activity with an ultralow overpotential of 9.2 mV at 10 mA cm−2 in 1 m KOH, and also achieves the competitive HER activity and stability in the acidic/neutral electrolytes. Both the experimental and computational results reveal the accelerated HER kinetics is attributable to the intensive mass transfer through the interfacial Ru→MoO2 hydrogen spillover effect. This work opens up the opportunities to rationalize the advanced metal‐support HER electrocatalysts through the interfacial hydrogen spillover effect and metallic bond engineering. [ABSTRACT FROM AUTHOR]

Efficient water dissociation to atomic hydrogen (H*) with restrained recombination of H* is crucial for improving the H* utilization for electrochemical dechlorination, but is currently limited by the lack of feasible electrodes. Herein, we developed a monolithic single‐atom electrode with Co single atoms anchored on the inherent oxide layer of titanium foam (Co1−TiOx/Ti), which can efficiently dissociate water into H* and simultaneously inhibit the recombination of H*, by taking advantage of the single‐atom reverse hydrogen spillover effect. Experimental and theoretical calculations demonstrated that H* could be rapidly generated on the oxide layer of titanium foam, and then overflowed to the adjacent Co single atom for the reductive dechlorination. Using chloramphenicol as a proof‐of‐concept verification, the resulting Co1−TiOx/Ti monolithic electrode exhibited an unprecedented performance with almost 100 % dechlorination at −1.0 V, far superior to that of traditional indirect reduction‐driven commercial Pd/C (52 %) and direct reduction‐driven Co1−N−C (44 %). Moreover, its dechlorination rate constant of 1.64 h−1 was 4.3 and 8.6 times more active than those of Pd/C (0.38 h−1) and Co1−N−C (0.19 h−1), respectively. Our research sheds light on the rational design of hydrogen spillover‐related electrocatalysts to simultaneously improve the H* generation, transfer, and utilization for environmental and energy applications. [ABSTRACT FROM AUTHOR]

In contrast to the energy‐intensive Haber‐Bosch process, the electroreduction of nitrate to ammonia presents a promising alternative. In this work, the Ni2P/Pd6P nanorods (named NiPdP‐NR) are successfully synthesized by using a simple phosphating process with NiIIPdII‐dimethylglyoxime complex (NiIIPdII‐DMG) nanorods as the precursor. Density functional theory calculations and electrochemical experiments prove that the introduction of Pd facilitates hydrogen spillover from Pd to Ni2P modulates the surface electronic structures, and therefore improves the catalytic kinetics of nitrate reduction ultimately. According to the dynamic experiment, the as‐prepared NiPdP‐NR shows high nitrate conversion efficiency (90.6%), selectivity of NH3 (93.4%), high Faradic efficiency (92.6%), and NH3 yield rate (0.908 mmol h−1 mgcat−1) for the nitrate reduction. [ABSTRACT FROM AUTHOR]

Electrocatalytic alkyne semihydrogenation under mild conditions is a more attractive approach for alkene production than industrial routes but suffers from either low production efficiency or high energy consumption. Here, we describe a tandem catalytic concept that overcomes these challenges. Component (i), which can trap hydrogen effectively, is partnered with component (ii), which can readily release hydrogen for hydrogenation, to enable efficient generation of active hydrogen on component (i) at low overpotentials and timely (i)‐to‐(ii) hydrogen spillover and facile desorptive hydrogenation on component (ii). We examine this concept over bicomponent palladium‐copper catalysts for the production of representative 2‐methyl‐3‐butene‐2‐ol (MBE) from 2‐methyl‐3‐butyne‐2‐ol (MBY) and achieve a record high MBE production rate of 1.44 mmol h−1 cm−2 and a Faraday efficiency of ~88.8 % at a low energy consumption of 1.26 kWh kgMBE−1. With these catalysts, we further achieve 60 h continuous production of MBE with record high profit space. [ABSTRACT FROM AUTHOR]

Recently, hydrogen spillover based binary (HSBB) catalysts have received widespread attention due to the sufficiently utilized reaction sites. However, the specific regulation mechanism of spillover intensity is still unclear. Herein, we have fabricated oxygen vacancies enriched Ru/NiMoO4‐x to investigate the internal relationship between electron supply and mechanism of hydrogen spillover enhancement. The DFT calculations cooperate with in situ Raman spectrum to uncover that the H* spillover from NiMoO4‐x to Ru. Meanwhile, oxygen vacancies weakened the electron supply from Ru to NiMoO4‐x, which contributes to dilute the resistance of built‐in electric field (BEF) for hydrogen spillover. In addition, the higher ion concentration in electrolyte will promote the H* adsorption step obviously, which is demonstrated by in situ EIS tests. As a result, the Ru/NiMoO4‐x exhibits a low overpotential of 206 mV at 3.0 A cm−2, a small Tafel slope of 28.8 mV dec−1, and an excellent durability of 550 h at the current density of 0.5 A cm−2 for HER in 1.0 M KOH seawater. [ABSTRACT FROM AUTHOR]

CO2 hydrogenation utilizing sustainably produced hydrogen and CO2 derived from industrial exhaust gas represents a pivotal technology for chemical energy storage and climate change mitigation. This work aims to identify the best combination of catalyst support, synthesis method and promotor for In2O3/ZrO2 catalysts in a typical fixed‐bed configuration. Intense characterization using ICP‐OES, XRD, XPS, N2‐physisorption, CO2‐TPD, H2‐TPR and SEM‐EDX provide molecular insights into the different effects caused by various synthesis methods and doping elements. Doping the most promising In2O3/ZrO2 (M‐SG) catalyst with 0.7 wt. % NiO by wetness impregnation using an ethanol/water mixture as a solvent, an increased methanol production rate of 0.497 gMeOH ⋅gcat1 ${{{\rm { \hskip0.17em}}{\rm { g}}}_{{\rm { cat}}}^{{\rm { 1}}}}$ ⋅ h−1 could already be achieved at 250 °C. Hereby, the low amount of highly dispersed NiO promotes H2 activation via hydrogen spillover, leading to sustained catalytic activity for 100 hours of time‐on‐stream. [ABSTRACT FROM AUTHOR]

The activation of molecular hydrogen is a key process in catalysis. Here, we demonstrate how polyoxometalate (POM)‐based heterogeneous compounds functionalized with Platinum particles activate H2 by synergism between a hydrogen spillover mechanism and electron‐proton transfer by the POM. This interplay facilitates the selective catalytic reduction of olefins and nitroarenes with high functional group tolerance. A family of polyoxotungstates covalently functionalized with boronic acids is reported. In the solid‐state, the compounds are held together by non‐covalent interactions (π–π stacking and hydrogen bonding). The resulting heterogeneous nanoscale particles form stable colloidal dispersions in acetonitrile and can be surface‐functionalized with platinum nanoparticles by in situ photoreduction. The resulting materials show excellent catalytic activity in hydrogenation of olefins and nitrobenzene derivatives under mild conditions (1 bar H2 and room temperature). [ABSTRACT FROM AUTHOR]

Herein, we reported that the platinum (Pt) clusters encapsulated into sodalite (SOD) zeolite as catalyst exhibited 100 % selectivity at 100 % conversion in the selective hydrogenation of p‐chloronitrobenzene to p‐chloroaniline via hydrogen spillover. The direct interaction between p‐chloronitrobenzene and encapsulated Pt was prevented by the shape selectivity of SOD zeolite, reactants were thereby adsorbed onto zeolite outer surface to facilitate the hydrogenation proceeding by hydrogen spillover process. The further kinetic study and DFT calculation showed the excellent catalytic selectivity was ascribed to the much faster rate of hydrogenation of adsorbed nitro group than that of adsorbed C−Cl group. [ABSTRACT FROM AUTHOR]

Hydrogenation of phenol to cyclohexanone/cyclohexanol is an important reaction in production of nylon‐6, nylon‐66 and in petroleum industry. Liquid phase phenol hydrogenation over Pd‐CuO/CeO2 was carried out under mild conditions. Palladium impregnated over CuO/CeO2 synthesized by co‐precipitation method showed excellent catalytic activity for phenol hydrogenation (99% conversion with 80% cyclohexanol yield) at 90 °C and 10 bar H2 pressure in water. Commercial 10%Pd/C showed only 8% phenol conversion under identical conditions. The detailed characterization revealed significant improvement in surface area of ceria after addition of CuO and decrease in crystallite size with creation of defects in CeO2 lattice. XPS analysis showed Pd loading on CuO/CeO2 to cause hydrogen spillover on the surface leading to increase in the oxygen vacancies. The interaction of phenol with catalyst surface studied by detailed FTIR analysis, revealed activation of phenol on oxygen vacancy of ceria as phenoxide ion with perpendicular orientation of aromatic ring on catalyst surface. [ABSTRACT FROM AUTHOR]

Hydrogenation of phenol to cyclohexanone/cyclohexanol is an important reaction in production of nylon‐6, nylon‐66 and in petroleum industry. Liquid phase phenol hydrogenation over Pd‐CuO/CeO2 was carried out under mild conditions. Palladium impregnated over CuO/CeO2 synthesized by co‐precipitation method showed excellent catalytic activity for phenol hydrogenation (99% conversion with 80% cyclohexanol yield) at 90 °C and 10 bar H2 pressure in water. Commercial 10%Pd/C showed only 8% phenol conversion under identical conditions. The detailed characterization revealed significant improvement in surface area of ceria after addition of CuO and decrease in crystallite size with creation of defects in CeO2 lattice. XPS analysis showed Pd loading on CuO/CeO2 to cause hydrogen spillover on the surface leading to increase in the oxygen vacancies. The interaction of phenol with catalyst surface studied by detailed FTIR analysis, revealed activation of phenol on oxygen vacancy of ceria as phenoxide ion with perpendicular orientation of aromatic ring on catalyst surface. [ABSTRACT FROM AUTHOR]

The hydrogenative ring‐opening of furfurals (furfural and 5‐methylfurfural) to linear diols (1,4‐pentanediol and 2,5‐hexanediol) is of great significance for bioderived fine chemical synthesis. Unfortunately, the catalytic activity and selectivity are unsatisfactory because of the interference of various side reactions, such as overhydrogenation to tetrahydrofurans. Herein, the preparation of an iodine (I) modified Pt‐based catalyst with abundant Pt‐I pairs is reported for the first time and shows high catalytic efficiency for linear diol synthesis with a yield of 80%–90% via the hydrogenative ring‐opening route, whereas bare Pt counterpart only shows tetrahydrofuran synthesis via the overhydrogenation route. The catalytic reaction mechanism shows the in‐situ hydrogen spillover‐promoted H−‐Pt‐I‐H+ pairs not only supply hydrogenation sites for the C=O hydrogenation step but also provide Brønsted acidic sites for the ring‐opening step. This work presents a feasible and convenient strategy for bifunctional catalysis with powerful linear diol synthesis over iodine‐modified noble metals. [ABSTRACT FROM AUTHOR]

Hydrogen spillover has attracted increasing interests in the field of electrocatalytic hydrogen evolution reaction (HER) in recent years because of their distinct reaction mechanism and beneficial terms for simultaneously weakening the strong hydrogen adsorption on metal and strengthening the weak hydrogen adsorption on support. By taking advantageous merits of efficient hydrogen transfer, hydrogen spillover‐based binary catalysts have been widely investigated, which paves a new way for boosting the development of hydrogen production by water electrolysis. In this paper, we summarize the recent progress of this interesting field by focusing on the advanced strategies for intensifying the hydrogen spillover towards HER. In addition, the challenging issues and some perspective insights in the future development of hydrogen spillover‐based electrocatalysts are also systematically discussed. [ABSTRACT FROM AUTHOR]

A well‐defined catalyst with platinum (Pt) and gold (Au) encapsulated in micropore and mesopore of micro‐mesoporous zeolite (Pt‐Au/TMSN), respectively, was designed to investigate the original active sites of semi‐hydrogenation. Specifically, hydrogen molecules are dissociated on Pt nanoclusters (NCs) to form hydrogen atoms that migrate to the surfaces of TMSN zeolite and Au nanoparticles (NPs) through hydrogen spillover effect. The characterization and catalytic results demonstrate that the Au NPs and zeolite surface are both identified as the semi‐hydrogenation sites. Especially, the Au active site with low adsorption ability of alkene possesses preferable selectivity in the semi‐hydrogenation of phenylacetylene and 1,5‐cyclooctadiene. Noteworthy, the Pt‐Au/TMSN exhibits higher selectivity of phenylethylene and cyclooctene than Pt/TMSN, as well as higher turnover frequency than Au/MSN. This work creates an effective regulation strategy of active sites working with a tandem mechanism for improving the semi‐hydrogenation performance. [ABSTRACT FROM AUTHOR]

Heterogeneous hydrogenation with hydrogen spillover has been demonstrated as an effective route to achieve high selectivity towards target products. More effort should be paid to understand the complicated correlation between the nature of supports and hydrogenation involving hydrogen spillover. Herein, we report the development of the hydrogenation system of hexagonal boron nitride (h‐BN)‐supported Pd nanoparticles for the hydrogenation of aldehydes/ketones to alcohols with hydrogen spillover. Nitrogen vacancies in h‐BN determine the feasibility of hydrogen spillover from Pd to h‐BN. The hydrogenation of aldehydes/ketones with hydrogen spillover from Pd proceeds on nitrogen vacancies on h‐BN. The weak adsorption of alcohols to h‐BN inhibits the deep hydrogenation of aldehydes/ketones, thus leading to high catalytic selectivity to alcohols. Moreover, the hydrogen spillover‐based hydrogenation mechanism makes the catalyst system exhibit a high tolerance to CO poisoning. [ABSTRACT FROM AUTHOR]

Currently, green hydrogen harvesting from electrochemical water splitting is overly reliant on noble metals with high catalytic activity but low natural abundance and high cost. As one of potential earth‐abundant alternatives, copper, however, displays a poor hydrogen evolving capability, mainly due to inherently a weak hydrogen binding energy (HBE). It poses a substantial restriction to metallic Cu alone serving as primary active sites for high‐performance hydrogen evolution. Thanks to the presence of hydrogen spillover that was often overlooked during the electrocatalysis, the hydrogen evolution in a nonacidic electrolyte can be accelerated by the recombination desorption of adsorbed hydrogen over Cu with a weak HBE. Here, we concisely highlighted this promotion effect of secondary active Cu on electrocatalytic hydrogen evolution and eagerly expected to extend hydrogen spillover effects to the advance of multi‐site electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Synergistic optimization of the elementary steps of water dissociation and hydrogen desorption for the hydrogen evolution reaction (HER) in alkaline media is a challenge. Herein, the Ru cluster anchored on a trace P‐doped defective TiO2 substrate (Ru/P‐TiO2) was synthesized as an electrocatalyst for the HER; it exhibited a commercial Pt/C‐like geometric activity and an excellent mass activity of 9984.3 mA mgRu−1 at −0.05 V vs. RHE, which is 34.3 and 18.7 times higher than that of Pt/C and Ru/TiO2, respectively. Experimental and theoretical studies indicated that using a rutile‐TiO2‐crystal‐phase substrate enhanced the HER activity more than the anatase phase. Rich surface oxygen vacancies on rutile‐TiO2 facilitated the adsorption and dissociation of water, while the partial substitution of Ti4+ with P5+ enhanced H2 generation by facilitating hydrogen spillover from the Ru site to the surface P site, synergistically enhancing the HER activity. [ABSTRACT FROM AUTHOR]

Synergistic optimization of the elementary steps of water dissociation and hydrogen desorption for the hydrogen evolution reaction (HER) in alkaline media is a challenge. Herein, the Ru cluster anchored on a trace P‐doped defective TiO2 substrate (Ru/P‐TiO2) was synthesized as an electrocatalyst for the HER; it exhibited a commercial Pt/C‐like geometric activity and an excellent mass activity of 9984.3 mA mgRu−1 at −0.05 V vs. RHE, which is 34.3 and 18.7 times higher than that of Pt/C and Ru/TiO2, respectively. Experimental and theoretical studies indicated that using a rutile‐TiO2‐crystal‐phase substrate enhanced the HER activity more than the anatase phase. Rich surface oxygen vacancies on rutile‐TiO2 facilitated the adsorption and dissociation of water, while the partial substitution of Ti4+ with P5+ enhanced H2 generation by facilitating hydrogen spillover from the Ru site to the surface P site, synergistically enhancing the HER activity. [ABSTRACT FROM AUTHOR]

Synergistic optimization of the elementary steps of water dissociation and hydrogen desorption for the hydrogen evolution reaction (HER) in alkaline media is a challenge. Herein, the Ru cluster anchored on a trace P‐doped defective TiO2 substrate (Ru/P‐TiO2) was synthesized as an electrocatalyst for the HER; it exhibited a commercial Pt/C‐like geometric activity and an excellent mass activity of 9984.3 mA mgRu−1 at −0.05 V vs. RHE, which is 34.3 and 18.7 times higher than that of Pt/C and Ru/TiO2, respectively. Experimental and theoretical studies indicated that using a rutile‐TiO2‐crystal‐phase substrate enhanced the HER activity more than the anatase phase. Rich surface oxygen vacancies on rutile‐TiO2 facilitated the adsorption and dissociation of water, while the partial substitution of Ti4+ with P5+ enhanced H2 generation by facilitating hydrogen spillover from the Ru site to the surface P site, synergistically enhancing the HER activity. [ABSTRACT FROM AUTHOR]

Synergistic optimization of the elementary steps of water dissociation and hydrogen desorption for the hydrogen evolution reaction (HER) in alkaline media is a challenge. Herein, the Ru cluster anchored on a trace P‐doped defective TiO2 substrate (Ru/P‐TiO2) was synthesized as an electrocatalyst for the HER; it exhibited a commercial Pt/C‐like geometric activity and an excellent mass activity of 9984.3 mA mgRu−1 at −0.05 V vs. RHE, which is 34.3 and 18.7 times higher than that of Pt/C and Ru/TiO2, respectively. Experimental and theoretical studies indicated that using a rutile‐TiO2‐crystal‐phase substrate enhanced the HER activity more than the anatase phase. Rich surface oxygen vacancies on rutile‐TiO2 facilitated the adsorption and dissociation of water, while the partial substitution of Ti4+ with P5+ enhanced H2 generation by facilitating hydrogen spillover from the Ru site to the surface P site, synergistically enhancing the HER activity. [ABSTRACT FROM AUTHOR]

A novel Zn−Fe flow battery featuring an Fe3+ reduction reaction (Fe3+RR)‐coupled zinc oxidation, and an Fe2+ oxidation reaction (Fe2+OR)‐coupled hydrogen evolution reaction (HER) system as well, was established. This battery is capable of driving two Fe2+OR‐coupled HER systems in series based on the above Fe2+/Fe3+ cycling, for efficient self‐powered hydrogen evolution. Meanwhile, this Fe2+/Fe3+ cycling enables the preparation of a multifunctional catalyst, Pt‐3@SXNS (siloxene nanosheet), by the Fe2+OR‐promoted dispersion of Pt nanoparticles on SXNS; alternatively, this support could be obtained by Fe3+RR‐assisted exfoliation using Fe3+ from the anolyte of Fe2+OR‐coupled HER. The Pt‐3@SXNS catalyst exhibits excellent catalytic activities toward Fe3+RR in the Zn−Fe flow battery, HER, and Fe2+OR in the electrolyzer, which is attributed to the strong electronic interaction between Pt and Si. This work offers a new strategy for energy storage and low‐cost hydrogen production from acidic wastewater. [ABSTRACT FROM AUTHOR]

Maximizing the Pt utilization is important for the widescale implementation of Pt‐based hydrogen evolution reaction (HER) electrocatalysts, owing to the scarcity of Pt. Here, three‐component heterostructured HER catalysts with ultrahigh Pt mass activity in which hollow PtCu alloy nanospheres are supported on an array of WO3 on Cu foam, are reported. It has been pointed out that the use of Pt counter electrode in a three‐electrode configuration in evaluating catalysts' HER performances in acidic media carries the risk of contaminating the working electrode in previous reports. Here, the authors rationally utilize this "contaminating" to "activate" low‐HER‐activity materials, maximizing the Pt utilization. As a result, ultrahigh Pt mass activity is achieved, that is 1.35 and 10.86 A mg−1Pt at overpotentials of 20 and 100 mV, respectively, 27 and 13 times higher than those of commercial Pt/C catalysts, outperforming some state‐of‐the‐art Pt‐single‐atom catalysts. The hollow sphere structure and PtCu alloying increase the number and reactivity of active sites. Density function calculations and electrochemical experiments reveal that the synergy between WO3 and Pt is also responsible for the high HER activity where the hydrogen spillover effect triggers the Volmer–Heyrovsky mechanism and promotes the rapid removal of H* from Pt to re‐expose the active sites. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) is regarded as a promising technology for biomass upgrading to obtain sustainable and competitive chemicals and fuels. In fact, biomass HDO over heterogeneous solid catalysts is often accompanied by the phenomenon of hydrogen spillover, which further affects the catalytic performance. Thus, it is necessary to gain in‐depth understand the promoting effect of hydrogen spillover in the biomass HDO process to obtain desired conversion and selectivity. This Review summarized the extensive research on hydrogen spillover in biomass refining and discussed in detail the regulation mechanism of hydrogen spillover in biomass HDO process, mainly by regulating different active center sites on catalyst supports, such as metal sites, acid sites, surface functional groups, and defective sites, which exhibit independent and synergistic characteristics promoting catalyst activity, selectivity, and stability. Finally, the prospective of hydrogen spillover in biomass HDO applications was critically evaluated, and the key technical challenges in developing "hydrogen‐free" HDO and upgrading biofuels were highlighted. The presentation of hydrogen spillover‐enhanced catalytic biomass HDO in this Review will hopefully provide insight and guidance for further development of efficient catalysts and preparation of high‐value chemicals in the future. [ABSTRACT FROM AUTHOR]

We demonstrate a modified sol‐immobilization procedure using (MeOH)x/(H2O)1‐x solvent mixtures to prepare Pd/TiO2 catalysts that are able to reduce the formation of acid catalyzed products, e. g. ethers, for the hydrogenation of furfural. Transmission electron microscopy found a significant increase in polyvinyl alcohol (PVA) deposition at the metal‐support interface and temperature programmed reduction found a reduced uptake of hydrogen, compared to an established Pd/TiO2 preparation. We propose that the additional PVA hinders hydrogen spillover onto the TiO2 support and limits the formation of Brønsted acid sites, required to produce ethers. Elsewhere, the new preparation route was able to successfully anchor colloidal Pd to the TiO2 surface, without the need for acidification. This work demonstrates the potential for minimizing process steps as well as optimizing catalyst selectivity – both important objectives for sustainable chemistry. [ABSTRACT FROM AUTHOR]

We demonstrate a modified sol‐immobilization procedure using (MeOH)x/(H2O)1‐x solvent mixtures to prepare Pd/TiO2 catalysts that are able to reduce the formation of acid catalyzed products, e. g. ethers, for the hydrogenation of furfural. Transmission electron microscopy found a significant increase in polyvinyl alcohol (PVA) deposition at the metal‐support interface and temperature programmed reduction found a reduced uptake of hydrogen, compared to an established Pd/TiO2 preparation. We propose that the additional PVA hinders hydrogen spillover onto the TiO2 support and limits the formation of Brønsted acid sites, required to produce ethers. Elsewhere, the new preparation route was able to successfully anchor colloidal Pd to the TiO2 surface, without the need for acidification. This work demonstrates the potential for minimizing process steps as well as optimizing catalyst selectivity – both important objectives for sustainable chemistry. [ABSTRACT FROM AUTHOR]

In previous work, nickel–molybdenum (NiMo) nanoparticles supported on cerium–zirconium oxide (CZ) catalyst showed excellent catalytic activity and stability for liquid fuel reforming with an improved coking resistance compared with Ni/CZ. Lowering the temperature of solid oxide fuel cells (SOFCs) below 700 °C is vital, because they can reduce the material costs and thermal stresses of SOFCs. However, the performance of NiMo/CZ is insufficient when operated at temperatures below 750 °C. This work aims to improve the activity and coking resistance of NiMo/CZ at a temperature of 700 °C by adding a minimal amount (0.1 wt%) of Ru. The Ru‐promoted sample shows a high reforming activity for partial oxidation of isooctane at 700 °C. The X‐ray diffraction (XRD) and STEM indicate a smaller Ni crystallite size for NiMoRu/CZ catalyst, which would decrease its tendency to facilitate coke formation. The tubular SOFC with the NiMoRu/CZ as its internal reforming catalyst displays good power density output and performance stability at 200 mA cm−2. [ABSTRACT FROM AUTHOR]

Surface oxygen‐containing functional groups of porous carbon have great influence on its various properties, including the catalytic performance, chemical stability, and adsorption capacity. In this paper, a catalytic hydrogen spillover method was proposed to prepare porous carbons with low oxygen content in 7 vol % H2/Ar atmosphere. Pt/C was used as the catalyst. Petroleum coke‐based porous carbon was adopted as the model material to study hydrogen spillover reduction effect within the temperature range of 500–700 °C. XRD, Raman and XPS were used to characterize the microstructures and surface chemical composition of prepared materials. Compared with H2 reduction, hydrogen spillover reduction can further increase graphitic degree of porous carbon without destroying the morphology and pore structure, and can reduce the contents of surface oxygen‐containing groups of porous carbon more effectively. And among different kinds of oxygen‐containing groups, the more reactive hydrogen atoms dissociated by Pt/C catalyst have the best reduction effect on C−O species. [ABSTRACT FROM AUTHOR]

High‐performance electrocatalysts for the hydrogen evolution reaction (HER) have an important role to play in the development of renewable energy. Platinum remains the most efficient known HER electrocatalyst. Therefore, it is necessary to find ways to maximize Pt utilization in actual practical applications. Herein we demonstrate a facile strategy for synthesizing RuCeOx‐supported, selectively loaded, atomic Pt (0.49 wt. %) (denoted Pt/RuCeOx‐PA) by photoactivation at ambient temperature and pressure. Through the photoelectron transfer at the Mott‐Schottky heterojunction in RuCeOx, Pt atoms became embedded into the RuO2 lattice. The resulting selectively loaded Pt‐O‐Ru moieties in Pt/RuCeOx‐PA give a stronger hydrogen spillover effect than Pt complexes randomly loaded by either chemical activation or thermal activation. As a result, Pt/RuCeOx‐PA shows superior HER performance to the materials prepared by random loading and is even better than a commercial Pt/C catalyst with much higher Pt loading (20 wt. %) at high current densities (from 50–600 mA cm−2). [ABSTRACT FROM AUTHOR]

Tuning CO2 hydrogenation selectivity to obtain targeted value‐added chemicals and fuels has attracted increasing attention. However, a fundamental understanding of the way to control the selectivity is still lacking, posing a challenge in catalyst design and development. Herein, we report our new discovery in ambient pressure CO2 hydrogenation reaction where selectivity can be completely reversed by simply changing the crystal phases of TiO2 support (anatase‐ or rutile‐TiO2) or changing metal loadings on anatase‐TiO2. Operando spectroscopy and NAP‐XPS studies reveal that the determining factor is a different electron transfer from metal to the support, most probably as a result of the different extents of hydrogen spillover, which changes the adsorption and activation of the intermediate of CO. Based on this new finding, we can not only regulate CO2 hydrogenation selectivity but also tune catalytic performance in other important reactions, thus opening up a door for efficient catalyst development by rational design. [ABSTRACT FROM AUTHOR]

The spillover of hydrogen species and its role in tuning the activity and selectivity in catalytic hydrogenation have been investigated in situ using surface‐enhanced Raman spectroscopy (SERS) with 10 nm spatial resolution through the precise fabrication of Au/TiO2/Pt sandwich nanostructures. In situ SERS study reveals that hydrogen species can efficiently spillover at Pt‐TiO2‐Au interfaces, and the ultimate spillover distance on TiO2 is about 50 nm. Combining kinetic isotope experiments and density functional theory calculations, it is found that the hydrogen spillover proceeds via the water‐assisted cleavage and formation of surface hydrogen–oxygen bond. More importantly, the selectivity in the hydrogenation of the nitro or isocyanide group is manipulated by controlling the hydrogen spillover. This work provides molecular insights to deepen the understanding of hydrogen activation and boosts the design of active and selective catalysts for hydrogenation. [ABSTRACT FROM AUTHOR]

The Fischer‐Tropsch reaction transforms syngas into high added value products, among which liquid fuels. Numerous parameters determine catalytic activity and selectivity towards the most desired hydrocarbons. The performances of cobalt‐based catalysts used in the reaction are known to depend critically on Co particle size and crystallographic phase. Here, we present a comparative study of Co‐based catalysts supported on three carbon supports: multi‐wall carbon nanotubes, carbon nanofibers and a fibrous material. Our results show that, while the selectivity towards C5+ follows the expected tendency with respect to Co particle size, this is not the case for the TOF. These results can be rationalized considering that the amount of H2 uptake on each catalyst increases with oxygen and defect concentration on the support. The catalyst on the support presenting many edges and oxygen surface groups, necessary for H2 spillover, presents the highest activity. Furthermore, the hydrogen spillover contributes to the enhancement of olefin hydrogenation and methane production. [ABSTRACT FROM AUTHOR]

Catalytic CO2 reduction to fuels and chemicals is a major pursuit in reducing greenhouse gas emissions. One approach utilizes the reverse water‐gas shift reaction, followed by Fischer–Tropsch synthesis, and iron is a well‐known candidate for this process. Some attempts have been made to modify and improve its reactivity, but resulted in limited success. Now, using ruthenium–iron oxide colloidal heterodimers, close contact between the two phases promotes the reduction of iron oxide via a proximal hydrogen spillover effect, leading to the formation of ruthenium–iron core–shell structures active for the reaction at significantly lower temperatures than in bare iron catalysts. Furthermore, by engineering the iron oxide shell thickness, a fourfold increase in hydrocarbon yield is achieved compared to the heterodimers. This work shows how rational design of colloidal heterostructures can result in materials with significantly improved catalytic performance in CO2 conversion processes. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) have attracted growing attention because they maximize the number of active sites, with unpredictable catalytic activity. Despite numerous studies on SACs, there is little research on the support, which is essential to understanding SAC. Herein, we systematically investigated the influence of the support on the performance of the SAC by comparing with single‐atom Pt supported on carbon (Pt SA/C) and Pt nanoparticles supported on WO3−x (Pt NP/WO3−x). The results revealed that the support effect was maximized for atomically dispersed Pt supported on WO3−x (Pt SA/WO3−x). The Pt SA/WO3−x exhibited a higher degree of hydrogen spillover from Pt atoms to WO3−x at the interface, compared with Pt NP/WO3−x, which drastically enhanced Pt mass activity for hydrogen evolution (up to 10 times). This strategy provides a new framework for enhancing catalytic activity for HER, by reducing noble metal usage in the field of SACs. [ABSTRACT FROM AUTHOR]