Spillover Mechanism Research Articles

Spillover effects of rural residents’ past pro-environmental production behavior on their voluntary waste separation behavior

Based on the survey data of rural residents in the National Ecological Civilization Pilot Area (Jiangxi), this paper empirically analyzes the spillover effect and mechanism of past pro-environmental production behavior on rural residents’ voluntary garbage sorting behavior, and adopts the fsQCA to clarify the grouping paths and examines the interactive relationship among multiple factors. The results of the empirical study show that: firstly, past pro-environmental production behaviors can directly promote rural residents’ voluntary garbage sorting behaviors; secondly, environmental self-identification and subjective norms have a partially mediating effect; thirdly, publicity and village regulations play a positive moderating effect. Further, the results of fsQCA analysis reaffirm the influence mechanisms, and reveal the multiple concurrent pathways through which past pro-environmental production behaviors drive the active waste sorting behaviors of rural residents. It’s found that there is a substitution relationship between rural residents’ past pro-environmental production behavior and publicity and education. This study enriches the theoretical explanation of the spillover of residents’ pro-environmental behaviors, and provides useful ideas for stimulating rural residents’ enthusiasm in active participation of rural residents in household waste sorting.

Contemporaneous Spillovers Across Foreign Exchange Markets

ABSTRACTThe study of financial shock propagation across markets has motivated numerous researchers to investigate the mechanisms of return and volatility spillovers in order to prevent harmful shock transmission. This article studies the contemporaneous spillovers by employing a structural vector autoregressive (SVAR) model with Markov switching covariance matrix to solve the identification problem. The proposed method offers a smooth convergence that handles several drawbacks of existing procedures. Moreover, this article develops a new framework to analyse the contemporaneous asymmetric volatility spillovers, which adds a great deal of knowledge by separating the effects of good news and bad news on shock transmissions. Application on major exchange rate returns and volatilities shows that the contemporaneous effects have different intensities for all pairwise currencies. Furthermore, the asymmetric analysis reveals that good (bad) volatility has a contemporaneous positive effect on good (bad) volatility, while the risk due to good (bad) news negatively affects the risk due to an opposite shock.

Mechanistic Understanding of Dissociated Hydrogen in Cu/CeO2-Catalyzed Methanol Synthesis.

The hydrogen dissociation and spillover mechanism on oxide-supported Cu catalysts play a pivotal role in the hydrogenation of carbon dioxide to methanol. This study investigates the hydrogen spillover mechanism on Cu/CeO2 catalysts using in situ spectral characterization under high-pressure reaction conditions and density functional theory (DFT) simulations. The research confirms that the Cu sites serve as the initial dissociation points for the hydrogen molecules. The chemically adsorbed hydrogen (H*) then spills over onto the CeO2 support and interacts with the lattice oxygen to form special hydroxyl groups, while simultaneously reducing the surrounding Ce4+ to form Ce3+. Interestingly, the temperature-programmed desorption (TPD) results found that heating the hydroxyl-containing surface mainly reverses H2 dissociation by desorbing H2 instead of forming H2O, while no significant vacancy formation was detected. The DFT calculation identified a subsurface pathway favoring hydrogen migration, which explained the dominating H2 in the TPD products. A chemical loop study after CO2/H2 cofeeding on the catalyst reveals that hydrogen spillover facilitates the highly reduced surface serving as the active centers, enabling a secondary methanol synthesis in a vacuum. This study provides a model of the formation and desorption pathways of hydrogen species on Cu/CeO2 catalysts and illustrates the key role of the hydrogen spillover mechanism in promoting the CO2 hydrogenation to methanol reaction through important experimental analysis.

Operando Unveiling of Hydrogen Spillover Mechanisms on Tungsten Oxide Surfaces.

Hydrogen spillover is an important process in catalytic hydrogenation reactions, facilitating H2 activation and modulating surface chemistry of reducible oxide catalysts. This study focuses on the operando unveiling of platinum-induced hydrogen spillover on monoclinic tungsten trioxide (γ-WO3), employing ambient pressure X-ray photoelectron spectroscopy, density functional theory calculations and microkinetic modeling to investigate the dynamic evolution of surface states at varied temperatures. At room temperature, hydrogen spillover results in the formation of W5+ and hydrogen intermediates (hydroxyl species and adsorbed water), facilitated by Pt metal clusters. With increasing temperature, water desorption, reverse hydrogen spillover and surface-to-bulk diffusion of hydrogen atoms compete with each other, leading initially to reoxidation and then further reduction of W atoms in the near-surface. The combined experimental results and simulations provide a comprehensive understanding of the mechanisms underlying hydrogen interaction with reducible metal oxides, lending insights of relevance to the design of enhanced hydrogenation catalysts.

Engineering the Metal/Oxide Interfacial O‐Filling Effect to Tailor Oxygen Spillover for Efficient Acidic Water Oxidation

AbstractThe oxygen spillover on the metal/oxide electrocatalysts interface acts as an essential role in promoting the oxygen evolution reaction (OER) for proton exchange membrane water electrolyzers (PEMWEs). However, oxygen spillover mechanisms and corresponding regulatory strategies are still unclear for addressing slow OH‐migration kinetics. Herein, an interface is constructed between Iridium (Ir) and Niobium (Nb)‐doped Titanium oxide (TiO2) with abundant oxygen vacancies area by plasma processing, enabling oxygen spillover from the metal Ir to supports. The optimized Ir/Nb‐doped TiO2 with a significant OER activity (η = 253 mV) and durability in acids compared to commercial IrO2. In situ experiments combined with theoretical computations reveal the presence of interfacial oxygen vacancies not only regulates the Ir structure toward boosted activity but also constructs a directional spillover pathway from Ir to interfacial oxygen vacancies area and then TiO2 via the OH*‐filling route, which strikingly mitigates the OH* migration barriers. In addition, the optimized Ir/Nb‐doped TiO2 exhibits excellent performance (1.69 V/1.0 A cm−2@80 °C) and long‐term stability (≈500 h@1.0 A cm−2) with practical potential in PEMWEs. This work provides a unique insight into the role of oxygen spillover, paving the way for designing Ir‐based catalysts for PEMWEs.

Lattice‐Matched Ru/W2C Heterointerfaces with Reversible Hydrogen Spillover for Efficient Alkaline Hydrogen Evolution

AbstractThe effect of lattice‐matched heterointerfaces on the hydrogen reverse spillover process for accelerating alkaline hydrogen evolution reaction (HER) kinetics has not yet been reported. Herein, a lattice‐matched Ru/W2C heterostructure is successfully constructed for effective hydrogen production. Experimental and theoretical results reveal that the Ru nanocluster can effectively stabilize W2C and thus promote the formation of phase‐pure W2C in the Ru/W2C heterostructure. In addition, it is revealed that H2O dissociation proceeded on W2C, and the formed H intermediates are subsequently migrated to adjacent interfacial Ru sites for H─H coupling and H2 release. This is enabled via a reversible hydrogen spillover mechanism promoted by the lattice‐matched heterointerfaces that can weaken interfacial proton adsorption. As expected, the Ru/W2C heterogeneous electrocatalyst exhibited a superior HER performance with a low overpotential of 17 mV at 10 mA cm−2, a high mass current density (6.44 A mgRu−1), and a low turnover frequency (TOF) value (2.8 s−1) at the overpotential of 100 mV, far overwhelming the benchmark Ru/C and Pt/C. The study may offer a new perspective for the design of highly active electrocatalysts for alkaline HER.

Fungal Phytopathogens: Their Role in the Spread and Management of Invasive Alien Plants

Biological invasions pose a major environmental challenge, often facilitating the unregulated dissemination of pathogens and parasites associated with their hosts. These pathogens can severely impact native and cultivated species, with far-reaching ecological and economic consequences. Despite their importance, the mycobiota associated with invasive plant species remains relatively understudied, posing a complex challenge for researchers. The aim of this manuscript is to underscore the most significant threats posed by the uncontrolled transmission of fungal pathogens from invasive alien plants to native environments and agricultural systems, and to identify the factors influencing this phenomenon. We emphasize the role of pathogen spillback and spillover mechanisms in the domestication of invasive alien plants. The influence of environmental, host, and pathogen-related factors on the survival of fungal pathogens were also investigated. Finally, we explore the technical and legal feasibility of using plant pathogens as “green agents” to control invasive alien plants.

Harnessing Ammonia as a Hydrogen Carrier for Integrated CO2 Capture and Reverse Water-Gas Shift.

In this paper, a concept of integrated CO2 capture and reverse water-gas shift (ICCrWGS) process was proposed using NH3 as the H2 carrier. The CO2 efficiency and total thermal energy consumption for the conventional rWGS, ICCrWGS using H2 (H2-ICCrWGS) and NH3 (NH3-ICCrWGS), were calculated. ICCrWGS using H2 and NH3 was conducted over the thermally stable Ni/CaZr dual-function materials (DFMs). NH3 decomposition, CO2 capture capacity, CO2 conversion, and CO selectivity were addressed at different reaction temperatures, and the optimal temperature was determined to be 650 °C. The Ni/CaZr DFMs exhibited stable CO2 capture capacity and CO productivity during ICCrWGS using the NH3 carrier. A carbonate spillover mechanism for CO production over the Ni/CaZr DFMs in NH3-ICCrWGS was proposed using in situ diffuse reflectance infrared Fourier transform spectroscopy. It was found that CO is produced from the bridged bidentate carbonate route in the Ni-CaO interface.

Role of hydrogen spillover on the hydrogenation of N-ethylcarbazole over in-situ Encapsulation of Ru within zeolite for hydrogen storage

Hydrogen spillover plays a crucial role in heterogeneous catalysis, significantly enhancing the activity of catalysts. However, the promotion mechanism of hydrogen spillover on non-reducible oxide supports (such as zeolite) is rarely reported. Herein, we prepared Ru@Beta sample by in-situ approach, effectively encapsulating Ru species into Beta zeolite. Additionally, three samples (Ru/SiO2, Ru@Naβ, and Ru@Hβ) with different hydrogen spillover effect were prepared. The optimal concentration of Ru was 0.5 wt%, and the Ru@Hβ sample with the strongest hydrogen spillover has 100 % conversion rate of N-ethylcarbazole (NEC) and 98 % selectivity towards to 12H-NEC. In contrast, the Ru/SiO2 with weak hydrogen spillover has only 89.5 % conversion rate and 28.9 % selectivity of 12H-NEC. Notably, the Ru@Hβ can still completely convert NEC even after 7 cycles, thereby exhibiting its remarkable activity and stability. Various characterizations (HAADF-STEM, XPS, EXAFS, in-situ DRIFT, and H2-TPD) indicate the superior catalytic performance of Ru@Hβ with strong hydrogen spillover effect, originating from the presence of more hydroxyl (–OH) and Brønsted acid on the surface, while Lewis acid act as hydrogen acceptors and NEC hydrogenation sites. This work not only expands our understanding of the hydrogen spillover, but also paves the way onto the potential applications in heterogeneous catalysis for efficient hydrogenation.

The Spatial Spillover Effect and Mechanism of Carbon Emission Trading Policy on Pollution Reduction and Carbon Reduction: Evidence from the Pearl River–West River Economic Belt in China

Abstract: China faces issues such as air pollution and global climate change, and the Carbon Emission Trading Policy (CETP) has attracted considerable attention as a core policy tool for achieving the "dual carbon" goals. Based on panel data from the Pearl River–West River Economic Belt (PRWREB) from 2008 to 2021, we use the Synthetic Control Method (SCM) and Spatial Difference-in-Differences (S-DID) models to explore the pollution reduction and carbon reduction effects of the CETP and its spatial heterogeneity. Our analysis reveals several interesting insights. First, the CETP has promoted a 34.1% overall reduction in pollution and carbon levels in the pilot areas, with sustained effects. Moreover, spatial spillover effects can reduce the pollution and carbon levels in the economic belt by 29.9%. Second, the pollution and carbon reduction effects of the CETP are more significant in regions with better economic development and active carbon trading. It has the best synergistic reduction effects on CO2 and SO2 but is less effective in reducing PM2.5. Third, the spillover effects of the CETP on technological innovation are greater than the direct effects, with the most noticeable pollution and carbon reduction outcomes. The overall negative effect on industrial structure is that it fails to promote pollution and carbon reduction. The emission reduction mechanisms vary for different targets: CO2 and PM2.5 are related to energy efficiency, SO2 to advancing industrial structure, and smoke and dust to technological innovation. Based on the research conclusions, we propose to improve the coordinated governance system for carbon and pollution, advance pollution and carbon reduction according to local conditions, and implement targeted emission reduction and efficiency enhancement.

Learning or Leaking? Enforcement Spillover Effects Within and Beyond the Firm

We posit and find evidence consistent with a new mechanism of intra-firm enforcement spillovers: the leakage of scarce compliance resources across facilities within a firm. Using a facility-level panel data set of Clean Air Act (CAA) enforcement actions from 2005 to 2017, we find a facility is more likely to violate the CAA following penalties on its same-industry-same-state siblings. In contrast, there is no significant spillover across firms. We show that the intra-firm spillover is not due to changes in regulatory attention or production shifting. Instead, our results suggest it may result from the redeployment of scarce compliance resources across siblings. Consistent with this mechanism, we find compliance leakage only occurs at privately held firms and facilities that lack the resources to invest in pollution prevention. The findings contribute to understanding the efficacy of environmental enforcement and have important implications for intra-firm management of environmental performance and regulatory enforcement approaches.

Research on the Impact Mechanism of Knowledge Spillover on the Growth of Small and Medium-sized Sports Enterprises

Background and Aim: In recent years, knowledge spillovers and enterprise innovation have become key drivers of the rapid development of small and medium-sized sports enterprises (SMEs) in China. This study conducted a questionnaire survey of 405 employees from SMEs using the snowball sampling method. The study focuses on how knowledge spillovers affect the development of SMEs in the sports industry and verifies the intrinsic links between knowledge spillovers, product innovation, model innovation, learning organizations, and firm growth variables. Materials and Methods: The study utilized SPSS 26.0 and AMOS 26.0 software for EFA and CFA. Additionally, the research hypotheses were tested using structural equation modeling with AMOS 26.0 software. Results: 1) Knowledge spillover, product innovation, model innovation, and learning organization all significantly enhance firm growth. 2)Learning organization, product innovation, and model innovation in SME sports enterprises mediate the effect of knowledge spillover on firm growth. 3)Learning organizations and product innovation, learning organizations, and model innovation in SMEs' sports enterprises jointly mediate the impact of knowledge spillovers on firm growth. 4)The study's results provide an in-depth analysis of how knowledge spillovers affect the development of SMEs through direct and indirect paths. This enriches the theory of sports enterprise development and helps promote enterprise growth. Conclusion: 1) Knowledge spillovers from SMEs directly boost enterprise growth. 2)Knowledge spillovers from SMEs can also indirectly enhance enterprise growth through factors like product innovation, model innovation, and learning organization. 3)Knowledge spillovers can further indirectly facilitate enterprise growth by influencing factors like enterprise learning organization, product innovation, and model innovation.

Maximizing Bifunctionality for Overall Water Splitting by Integrating H2 Spillover and Oxygen Vacancies in CoPBO/Co3O4 Composite Catalyst

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.

Boosting Hydrogen Transport in Mixed Matrix Membranes Through Continuous Spillover Via Pd‐Functionalized MOF Gel Networks

AbstractMembrane‐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.

Tail risk spillovers in the stock and forex markets at the major emergencies: Evidence from the G20 countries

We explore the tail risk spillover in the stock and foreign exchange (forex) markets along the G20 countries based on the tail-event driven network (TENET) method. To effectively capture the risk spillover mechanism from the tail-dependence perspective, we analyze the network connectedness in four aspects (namely system, market, region, and country) and explore it at the major emergencies. We find that (i) the system-level risk spillover peaks at the US subprime crisis, and subsequently undergoes several cyclical volatility in relatively high level in the period of major emergencies; (ii) the cross-market risk spillover from the stock markets to the forex markets plays a dominant role, while that from the forex markets to the stock markets is small; and (iii) the stock and forex markets in Europe and America transmit the large tail risk spillovers to other regions, and the forex markets in these regions are sensitive to the major emergencies.

Structural design and electronic regulation of atomically dispersed Mo-S4 sites by second shell N species reconfiguration for intensifying hydrogen spillover

Intensifying hydrogen spillover by regulating the atomic local structures catalysts is crucial for improving the hydrogenation performance, but still hugely challenging. Herein, we report a robust single-atom catalyst featuring Mo-S4 sites in the first shell modulated with N atoms in the second shell (Mo-S4-N/C) by an efficient cyclodextrin supramolecular self-assembly pyrolysis strategy for intensifying hydrogen spillover in slurry-phase hydrocracking of vacuum residue (VR). We discovered that the H2 is activated at the single-atom Mo-S4 sites efficiently and the spillover of active hydrogen is accelerated by the reconfiguration of N species in the second shell. Remarkably, the Mo-S4-N/C catalyst demonstrates excellent catalytic hydrogenation activity with high turnover frequency calculated for total metals up to 0.46 s−1, the VR per pass conversion of 61 wt.%, liquid product yield of 94 wt.%, and the low coke content of 0.6 wt.%, along with good stability, respectively. Theoretical calculations revealed that the N species in the second shell regulated the electronic structure of Mo-S4 sites, promoting the migration of active hydrogen species by reducing the transfer energy barrier of hydrogen spillover, thus enhancing the hydrogenation performance. This work proposed a strengthened hydrogen spillover mechanism from the atomic scale for hydrogenation reaction, offering novel concepts for designing and developing high-performance hydrogenation catalysts.

Hydrogen Spillover Mechanism of Superaerophobic NiSe2‐Ni5P4 Electrocatalyst to Promote Hydrogen Evolution in Saline Water

AbstractThe 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.

Intellectual property rights protection and sustainable innovation performance: The mediating role of technology spillover

AbstractDespite extensive research into the factors driving sustainable innovation, there remains a significant gap in understanding the impact of intellectual property rights (IPR) protection. This study delves into how IPR protection influences sustainable innovation performance and explores the mechanism of technology spillover and the condition of absorptive capacity. Analyzing data from 266 firms in Vietnam, our findings indicate a positive correlation between IPR protection and technology spillover. Additionally, we find that technology spillover mediates the relationship between IPR protection and sustainable innovation performance. Interestingly, we show that absorptive capacity bolsters the relationship between technology spillover and sustainable innovation performance. These insights offer valuable additions to the existing literature on IPR protection and sustainable innovation literature. Implications for both theory and practice are discussed in detail.

Cultural re-importation through soft power and transnational cultural flows mediated by digital influence: the case of city pop music in Japan, Malaysia and Indonesia

Japanese popular culture (pop culture) has penetrated and influenced foreign cultural markets through various means. Japanese city pop music, popular from the 1970s through the 1980s, has charted a new trajectory in this transnational cultural spillover. The attractiveness of the city pop genre was rediscovered abroad; the hit songs were disseminated through social media, which eventually led to a revival of this genre’s popularity in Japan. This study refers to this phenomenon as cultural re-importation and proposes some theoretical deliberations to capture it. It recognises that the complex process of re-importation is mediated by digital means of communication, such as social media platforms YouTube and TikTok. This study employs three theoretical perspectives on the cultural spillover mechanism, namely, Japan’s soft power, transnational cultural flows, and digital influence. To elucidate these processes empirically, we analysed data from in-depth interviews with 35 young people from Malaysia, Indonesia, and Japan. Secondary data were collected as well, including online news and media releases. Based on the interview findings, this study posits that cultural re-importation is a complex interplay of several factors.

Cr dopant mediates hydroxyl spillover on RuO2 for high-efficiency proton exchange membrane electrolysis

Simultaneously improving the activity and stability of catalysts for anodic oxygen evolution reaction (OER) in proton exchange membrane water electrolysis (PEMWE) remains a notable challenge. Here, we report a chromium-doped ruthenium dioxide with oxygen vacancies, termed Cr0.2Ru0.8O2-x, that drives OER with an overpotential of 170 mV at 10 mA cm−2 and operates stably over 2000 h in acidic media. Experimental and theoretical studies show that the synergy of Cr dopant and oxygen vacancy induces an unconventional dopant-mediated hydroxyl spillover mechanism. Such dynamic hydroxyl spillover from Cr dopant to Ru active site changes the rate-determining step from OOH* formation to O2 formation and thus greatly improves the OER performance. Moreover, the Cr dopant and oxygen vacancy also play a crucial role in stabilizing surface Ru and lattice oxygen in the Ru-O-Cr structural motif. When assembled into the anode of a practical PEMWE device, Cr0.2Ru0.8O2-x enables long-term durability of over 200 h at an ampere-level current density and 60 degrees centigrade.