Developing highly efficient and durable electrocatalysts for hydrogen evolution reaction (HER) under both alkaline and acidic media is crucial for the future development of a hydrogen economy. ...However, state‐of‐the‐art high‐performance electrocatalysts recently developed are based on carbon carriers mediated by binding noble elements and their complicated processing methods are a major impediment to commercialization. Here, inspired by the high‐entropy alloy concept with its inherent multinary nature and using a glassy alloy design with its chemical homogeneity and tunability, we present a scalable strategy to alloy five equiatomic elements, PdPtCuNiP, into a high‐entropy metallic glass (HEMG) for HER in both alkaline and acidic conditions. Surface dealloying of the HEMG creates a nanosponge‐like architecture with nanopores and embedded nanocrystals that provides abundant active sites to achieve outstanding HER activity. The obtained overpotentials at a current density of 10 mA cm−2 are 32 and 62 mV in 1.0 m KOH and 0.5 m H2SO4 solutions, respectively, outperforming most currently available electrocatalysts. Density functional theory reveals that a lattice distortion and the chemical complexity of the nanocrystals lead to a strong synergistic effect on the electronic structure that further stabilizes hydrogen proton adsorption/desorption. This HEMG strategy establishes a new paradigm for designing compositionally complex alloys for electrochemical reactions.
A high‐entropy metallic glass with multinary nature and chemical homogeneity is developed by a scalable metallurgical technique. Dealloying creates a nanosponge‐like architecture with embedded nanocrystals that provides abundant active sites to achieve outstanding hydrogen evolution activity in both alkaline and acidic conditions. This work will provide a roadmap for designing alloy catalysts for many years to come.
Metallic glasses (MGs) with the metastable nature and random atomic packing structure have attracted large attention in the catalytic family due to their superior catalytic performance. In contrast, ...their crystalline counterparts are restricted by the highly ordered packing structure, fewer surface active sites, and crystallographic defects for catalytic activity. The uncertainty of the different catalytic mechanisms and the intrinsic characteristics correlated to MGs and their crystalline counterparts become a major impediment to promote their catalytic efficiencies and widespread applications. Herein, it is reported that the excellent catalytic behavior in Fe‐based MGs goes through a detrimental effect with the partial crystallization, but receives a compelling rejuvenation in the full crystallization. Further investigation reveals that multiphase intermetallics with electric potential differences in fully crystallized alloys facilitate the formation of galvanic cells. More importantly, extensively reduced grain boundaries due to grain growth greatly weaken electron trapping and promote inner electron transportation. The relatively homogenous grain‐boundary corrosion in the intermetallics contributes to well‐separated phases after reaction, leading to refreshment of the surface active sites, thereby quickly activating hydrogen peroxide and rapidly degrading organic pollutants. The exploration of catalytic mechanisms in the crystalline counterparts of MGs provides significant insights into revolutionize novel catalysts.
Fully crystallized alloys gained by annealing of metallic glasses show excellent rejuvenated catalytic capabilities for ultrafast activation of peroxide. As galvanic cells form in the fully crystallized alloys, a grain growth contributing to extensively reduced grain boundaries greatly weakens electron trapping and promotes inner electron transportation, providing a significant insight into exploit novel catalysts.
Metallic glass (MG), with the superiorities of unique disordered atomic structure and intrinsic chemical heterogeneity, is a new promising and competitive member in the family of environmental ...catalysts. However, what is at stake for MG catalysts is that their high catalytic efficiency is always accompanied by low stability and the disordered atomic configurations, as well as the structural evolution, related to catalytic performance, which raises a primary obstacle for their widespread applications. Herein, a non‐noble and multicomponent Fe83Si2B11P3C1 MG catalyst that presents a fascinating catalytic efficiency while maintaining remarkable stability for wastewater remediation is developed. Results indicate that the excellent efficiency of the MG catalysts is ascribed to a unique atomic coordination that causes an electronic delocalization with an enhanced electron transfer. More importantly, the in situ self‐reconstructed hierarchical gradient structure, which comprises a top porous sponge layer and a thin amorphous oxide interfacial layer encapsulating the MG surface, provides matrix protection together with high permeability and more active sites. This work uncovers a new strategy for designing high‐performance non‐noble metallic catalysts with respect to structural evolution and alteration of electronic properties, establishing a solid foundation in widespread catalytic applications.
Fe‐based metallic glass catalysts with a disordered atomic structure are prepared by a melt‐spinning technique. The metallic glass catalysts present excellent catalytic performance in both efficiency and stability when compared to the state of the art. The high catalytic efficiency is due to their intrinsic formation of metallic bonds and electronic delocalization, while the superior catalytic stability is owing to their self‐reconstruction ability.
To reduce the economic loss caused by scale formation and corrosion of equipment and pipelines, a low phosphorus polymer scale inhibitor is synthesized and characterized, the ability of the polymer ...to mitigate the calcium scale and the influences of operating conditions on CaCO3 scale are investigated by static tests. X‐ray diffraction (XRD) and scanning electron microscope (SEM) studies are performed to understand the morphological changes of the scales in the presence of the polymer. The interaction between polymer molecules and calcite crystal surface is studied by molecular dynamics simulation. The synthesized polymer is compared with the commercial product such as hydrolysis polymaleic acid (HPMA), polyacrylic acid (PAA), and 1‐hydroxy ethylidene‐1,1‐diphosphonic acid (HEDP). The experimental results show that the polymer shows better inhibition of calcium scale than the commercial product. The scale inhibition efficiency of the polymer is 92% at 10 mg/L for CaCO3 scale, 83% at 14 mg/L for Ca3(PO4)2 scale, and 98% at 6 mg/L for CaSO4 scale. SEM and XRD analysis show that the polymer induces the conversion of CaCO3 from calcite to arachite and crystal. The interaction of the polymer with both 104 and 1–10 calcite crystal surfaces are more stable than that of commercial product. The experimental results are in good agreement with those of molecular dynamics simulation.
CaCO3 morphology before and after scal inhibitor application.
Recently, we demonstrated that
(PG2), the active ingredient in dried roots of
ameliorates cancer symptom clusters and improves quality of life (QoL) in patients with metastatic disease by modulating ...inflammatory cascade against the background roles of inflammatory cells, including macrophages, dendritic cells (DCs), and cytotoxic T lymphocytes (CTLs) in tumor initiation, metastasis, and progression. Nevertheless, the role of PG2 in the modulation of anticancer immunogenicity and therapeutic response remains relatively underexplored and unclear.
The present study investigates how and to what extent PG2 modulates cellular and biochemical components of the inflammatory cascade and enhances anticancer immunity, as well as the therapeutic implication of these bio-events in patients with lung cancer.
Herein, we demonstrated that PG2 significantly increased the M1/M2 macrophage polarization ratio in non-small cell carcinoma (NSCLC) H441 and H1299 cells. This PG2-induced preferential pharmacologic up-regulation of tumoral M1 population in vitro positively correlated with the downregulation of tumor-promoting IL-6 and IL-10 expression in NSCLC cell-conditioned medium, with concomitant marked inhibition of cell proliferation, clonogenicity, and tumorsphere formation. Our ex vivo results, using clinical sample from our NSCLC cohort, demonstrated that PG2 also promoted the functional maturation of DCs with consequent enhancement of T cell-mediated anticancer immune responses. Consistent with the in vitro and ex vivo results, our in vivo studies showed that treatment with PG2 elicited significant time-dependent depletion of the tumor-associated M2 population, synergistically enhanced the anti-M2-based anticancer effect of cisplatin, and inhibited xenograft tumor growth in the NSCLC mice models. Moreover, in the presence of PG2, cisplatin-associated dyscrasia and weight-loss was markedly suppressed.
These results do indicate a therapeutically-relevant role for PG2 in modulating the M1/M2 macrophage pool, facilitating DC maturation and synergistically enhancing the anticancer effect of conventional chemotherapeutic agent, cisplatin, thus laying the foundation for further exploration of the curative relevance of PG2 as surrogate immunotherapy and/or clinical feasibility of its use for maintenance therapy in patients with lung cancer.
Heat and mass transports through a rough surface are among the most fundamental and important phenomena in either natural or engineering problems. In this paper, theoretical modelling and direct ...simulation Monte Carlo method are employed to study the heterogeneous reaction–diffusion features induced by microscale roughness which is comparable to the molecular mean free path of the ambient gas. A quasi-one-dimensional homogeneous model is proposed, and it consists of an external diffusion region outside the roughness elements and an internal reaction–diffusion region which could be equivalent to a smooth surface with an effective chemical property. The external macroscopic diffusion can be characterized by a non-equilibrium criterion – the Damköhler number. The internal diffusion in micro-cavities must be analysed by considering the rarefied gas effects on the diffusivity, and another non-equilibrium criterion, the Thiele number, is introduced to evaluate the effective boundary condition imposed on the external region. Analytical formulae based on these criteria are derived to predict the equivalent surface reaction–diffusion performance, and the predictions compare well with the numerical results of different types of surface reaction, even on the three-dimensional roughness. This reveals that the roughness could either enhance or weaken the apparent reaction rate depending on the non-equilibrium degree. This study could enrich our understanding of the gas–surface interactions on a rough wall, such as the oxidation, catalysis and energy accommodation, and also preliminarily provides a practical method for evaluation of the aerothermochemical performance of coating materials of hypersonic vehicles.
In non-small cell lung cancer (NSCLC), the most frequent oncogenic mutation in western countries is
KRAS
, for which, however, there remains no clinically approved targeted therapies. Recent progress ...on high biological heterogeneity including diverse
KRAS
point mutations, varying dependence on mutant
KRAS
, wide spectrum of other co-occurring genetic alterations, as well as distinct cellular status across the epithelial-to-mesenchymal transition (EMT), has not only deepened our understanding about the pathobiology of
KRAS
-mutant NSCLC but also brought about unprecedented new hopes for precision treatment of patients. In this review, we provide an update on the most recent advances in
KRAS
-mutant lung cancer, with a focus on mechanistic insights into tumor heterogeneity, the potential clinic implications and new therapies on horizons tailored for
KRAS
-mutant lung cancer.
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Due to the great limitation of glass forming ability, precisely controlling the chemical compositions of metallic glasses (MGs) still dramatically inhibits their widespread ...applications in wastewater remediation. Here, heterostructured catalysts were exploited by rapid annealing of Fe-based MGs and subsequent ball milling (BM) as advanced alternatives for amorphous counterparts in Fenton-like process. It was found that the surface characteristics tailored by ball milling enable more chemically active sites due to its enlarged specific surface area, surface defects and nanosized amorphous oxide layer that significantly enhance surface-catalyzed reaction in Fenton-like process. On the other hand, high-temperature annealing induced grain growth and electrochemical potential difference induced effect of galvanic cells in multiple crystalline phases (e.g. α-Fe (Si), Fe2B and Fe3Si) further provide an important contribution to high efficiency of electron transfer in heterostructured catalysts. Since the multiphase heterostructure is easily formed by a high-temperature annealing of MGs/amorphous-crystalline composite alloys, this work aims to provide an advanced alternative of MG catalyst without the elemental limitation of glass forming ability for wastewater remediation.
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•Fe-based metallic glass matrix composite was produced by selective laser melting.•45 times reusability was achieved in sulfate radical-based reaction.•Extremely low surface decay and ...precipitation promoted reusability of composite.•Volume fraction of phases affected the catalytic efficiency in the composite.•Excellent overall catalytic ability could be found in the composite.
The ever-increasing environmental consciousness has stimulated new design of catalysts to meet environmental requirements due to rapid expansion of industrialization. Additive manufacturing now emerges as a novel technology that revolutionizes the way of material manufacturing with functional applications. Herein, the manufacturing of an Fe-based metallic glass (MG) matrix composite with three-dimensional rhombic dodecahedron microstructure by selective laser melting (SLM) is reported. The SLM-produced porous Fe-based MG matrix composite has been employed into catalytic activation in Fenton-like process and sulfate radical-based reaction. Results demonstrate that up to 45 times reusability is achieved in sulfate radical-based reaction without any apparent efficiency decay, which is the highest reusability with high efficiency by catalysts as of now. The remarkable catalytic reusability originates from extremely low surface decay in sulfate radical-based reaction. In addition, structural analysis indicates the α-Fe nanocrystals could trigger easy electron transfer but a large amount of α-Fe lead to an inhibitive catalytic effect in the MG matrix composite. The overall catalytic ability also demonstrates the excellent catalytic performance of SLM-produced porous Fe-based MG matrix composite in the wastewater remediation. This work suggests a novel SLM-produced catalyst with promising industrial potential and value.
The room-temperature phosphorescence of 1,8-naphthalimide was activated by doping it into aromatic dicarboxylic acids. The doping system gives a bright yellow afterglow and 1,8-naphthalimide and ...isophthalic acid (0.02 mol% doping content) afford a phosphorescent lifetime of 403 ms and a quantum yield of 4.2%. Both energy transfer from the host to the guest and the formation of an intermolecular hydrogen-bonding network are responsible for the observed efficient and long-lived phosphorescence.
The parent 1,8-naphthalimide, which is otherwise room-temperature phosphorescence inert, was activated by doping into aromatic dicarboxylic acids, leading to efficient and long-lived phosphorescent emission.
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