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Processive hydrogenolysis catalysts, in which a metal nanoparticle (e.g., Pt) embedded at the bottom of a cylindrical silica nanopore can repeatedly cleave polymer chains and produce value-added hydrocarbon products, offer a potential solution for billions of tons of waste plastics. As the chain stays longer near the Pt catalysts, it would have a higher chance of getting cut, and therefore the molecular weight distribution of the product could be affected by the adsorption behavior of virgin chains (long polymers) versus cleaved chains (short polymers) into the nanopores. This work reports a model study to understand the competitive adsorption behavior of the two different molecular weight polymers that are mixed, mimicking the reaction medium in the intermediate stage of the catalytic reaction. This study employs small-angle neutron scattering (SANS), which takes advantage of contrast differences between hydrogenous and deuterated polystyrenes to experimentally observe the relative composition of the two polymers in the silica nanopores. Our results reveal preferential adsorption of longer chains in the silica nanopores, which is consistent with the theoretical prediction in the literature for the case of the enthalpic attraction between polymers and pore walls.

The surface complexation engineering of perovskite based on 4-tert-butylpyridine molecules is utilized to achieve high-performance and stable perovskite solar cells.

While Ru-catalyzed hydrogenolysis holds significant promise in converting waste polyolefins into value-added alkane fuels, a major constraint is the high cost of noble metal catalysts. In this work, we propose, for the first time, that Co-based catalysts derived from CoAl-layered double hydroxide (LDH) are alternatives for efficient polyolefin hydrogenolysis. Leveraging the chemical flexibility of the LDH platform, we reveal that metallic Co species serve as highly efficient active sites for polyolefin hydrogenolysis. Furthermore, we introduced Ni into the Co framework to tackle the issue of restricted hydrogenation ability associated with contiguous Co–Co sites. In-situ analysis indicates that the integration of Ni induces electron transfer and facilitates hydrogen spillover. This dual effect synergistically enhances the hydrogenation/desorption of olefin intermediates, resulting in a significant reduction in the yield of low-value CH4from 27.1 to 12.6%. Through leveraging the unique properties of LDH, we have developed efficient and cost-effective catalysts for the sustainable recycling and valorization of waste polyolefin materials.

Rechargeable aqueous zinc ion batteries (AZIBs) have gained considerable attention owing to their low cost and high safety, but dendrite growth, low plating/stripping efficiency, surface passivation, and self-erosion of the Zn metal anode are hindering their application. Herein, a one-step in situmolecular engineering strategy for the simultaneous construction of hierarchical MoS2double-layer nanotubes (MoS2-DLTs) with expanded layer-spacing, oxygen doping, structural defects, and an abundant 1T-phase is proposed, which are designed as an intercalation-type anode for “rocking-chair” AZIBs, avoiding the Zn anode issues and therefore displaying a long cycling life. Benefiting from the structural optimization and molecular engineering, the Zn2+diffusion efficiency and interface reaction kinetics of MoS2-DLTs are enhanced. When coupled with a homemade ZnMn2O4cathode, the assembled MoS2-DLTs//ZnMn2O4full battery exhibited impressive cycling stability with a capacity retention of 86.6% over 10 000 cycles under 1 A g–1anode, outperforming most of the reported “rocking-chair” AZIBs. The Zn2+/H+cointercalation mechanism of MoS2-DLTs is investigated by synchrotron in situpowder X-ray diffraction and multiple ex situcharacterizations. This research demonstrates the feasibility of MoS2for Zn-storage anodes that can be used to construct reliable aqueous full batteries.

The classic cartoon “Calabash Brothers” describes a story of seven brothers born from a magic gourd uniting to defeat powerful enemies. In order to explore the secret of the magic gourd, several transition metals were used to synthesize metal silicates (C-MSi) by planted gourd leaves (GLs) and then the C-MSi materials were used to fabricate supercapacitor electrodes and devices with superior electrochemical performance. By integrating theoretical calculations and experimental results, the supercapacitor electrodes and devices obtained from the combination of transition metals with amorphous carbon exhibit superior electrochemical performance. In detail, in the three-electrode system, the NaOH etched materials (C-MSi) exhibited better electrochemical performance (for instance, as for C-CdSi, 607 F g−1at 0.5 A g−1and the capacitance retention of 98.2% after 10,000 cycles) than the unetched ones (i-C-MSi). Hybrid supercapacitor (HSC) devices also achieve very excellent electrochemical properties. Take C-CdSi//AC as an example, the areal specific capacitance with 691 mF cm−2at 2 mA cm−2, the energy density with 5.04 Wh m−2at the power density of 22.2 W m−2and the cycle stability with 87.3% after 6,000 cycles. This approach is very versatile and was also applied to produce many hierarchically structured metal-silicate materials of other biomass precursors, including roots, vines, flowers, fruits and seeds of the planted gourds. Thus, it is a potential way to prepare transition metal silicates using biomaterials for the enhancement of electrochemical performance and improvement of energy storage and conversion. Also, this paper preliminarily reveals the secret of the magic gourd.

Driving metal-cluster-catalyzed high-temperature chemical reactions by sunlight holds promise for the development of negative-carbon-footprint industrial catalysis, which has yet often been hindered by the poor ability of metal clusters to harvest and utilize the full spectrum of solar energy. Here, we report the preparation of Mo2TiC2MXene-supported Ru clusters (Ru/Mo2TiC2) with pronounced broadband sunlight absorption ability and high sintering resistance. Under illumination of focused sunlight, Ru/Mo2TiC2can catalyze the reverse water–gas shift (RWGS) reaction to produce carbon monoxide from the greenhouse gas carbon dioxide and renewable hydrogen with enhanced activity, selectivity, and stability compared to their nanoparticle counterparts. Notably, the CO production rate of MXene-supported Ru clusters reached 4.0 mol·gRu–1·h–1, which is among the best reported so far for photothermal RWGS catalysts. Detailed studies suggest that the production of methane is kinetically inhibited by the rapid desorption of CO from the surface of the Ru clusters.

While tuning the electronic structure of Pt can thermodynamically alleviate CO poisoning in direct methanol fuel cells, the impact of interactions between intermediates on the reaction pathway is seldom studied. Herein, we contrive a PtBi model catalyst and realize a complete inhibition of the CO pathway and concurrent enhancement of the formate pathway in the alkaline methanol electrooxidation. The key role of Bi is enriching OH adsorbates (OHad) on the catalyst surface. The competitive adsorption of CO adsorbates (COad) and OHadat Pt sites, complementing the thermodynamic contribution from alloying Bi with Pt, switches the intermediate from COadto formate that circumvents CO poisoning. Hence, 8% Bi brings an approximately 6-fold increase in activity compared to pure Pt nanoparticles. This notion can be generalized to modify commercially available Pt/C catalysts by a microwave-assisted method, offering opportunities for the design and practical production of CO-tolerance electrocatalysts in an industrial setting.

Concrete can be regarded as a composite material with aggregates embedded in hardened slurries. The size, shape and distribution of aggregates directly affect multiple properties of concrete, including mechanical properties, ultrasonic field characteristics of concrete and ground penetrating radar (GPR) wave field characteristics. Therefore, conducting in-depth research on the random generation model of two-dimensional irregular aggregates is particularly important. This article introduces a fast grid region division method (FGRDM), which is an efficient reconstruction algorithm designed for two-dimensional concrete aggregate models. The algorithm takes into consideration the random micro-aggregate structure of concrete. A two-dimensional random distribution model of irregular aggregates in concrete was successfully established by generating concrete models with different particle size distributions and aggregate contents. Furthermore, the finite difference time domain method was used to analyze the GPR wave field of the random model. The significant influence of aggregate shape and distribution on the GPR wave field was discussed. Compared with existing two-dimensional irregular aggregate random generation models, the FGRDM proposed in this paper avoids computational redundancy and generates irregular aggregates at an increasingly fast speed. In the analysis of GPR data, electromagnetic waves are greatly affected by the shape and distribution of aggregates, highlighting the critical role of two-dimensional random distribution models in GPR data analysis. The paper uses FGRDM to generate random irregular aggregates to simulate the distribution of aggregates in actual concrete. Different diameter glass fiber reinforced polymer (GFRP) bars are inserted into the actual concrete and the numerical model to investigate the effect of aggregate size on the recognition of different diameter GFRP bars. The simulation results are generally consistent with the experimental results.

In deep ground engineering, the use of high-strength and high-toughness steels for rock bolt can significantly improve its energy absorption capacity. However, the mechanisms and effects of rock loading conditions on this kind of high energy-absorbing steel for rock bolt remain immature. In this study, taking Muzhailing highway tunnel as the background, physically based crystal plasticity simulations were performed to understand the effect of rock loading rate and pretension on the deformation behaviors of twinning induced plasticity (TWIP) steel used for rock bolt. The material physical connecting to the underlying microscopic mechanisms of dislocation glide and deformation twinning were incorporated in numerical modeling. The rock loading conditions were mimicked by the real-time field monitoring data of the NPR bolt/cable equipment installed on the tunnel surrounding rock surface. The results indicate that the bolt rod exhibits pronounced deformation-softening behavior with decrease of the loading rate. There is also a sound deformation-relaxation phenomenon induced by the dramatic decrease of loading rate after pre-tensioning. The high pretension (>600 MPa or 224 kN) can help bolt rod steel resist deformation-softening behavior, especially at low loading rate (<10−1 MPa/s or 10−2 kN/s). The loading rate was found to be a significant factor affecting deformation-softening behavior while the pretension was found to be the major parameter accounting for the deformation-relaxation scenario. The results provide the theoretical basis and technical support for practical applications.

Lead halide perovskite nanocrystals (CsPbX3NCs) have been regarded as promising materials in photocatalysis. Combining metal single atoms with CsPbX3NCs may be a practical way in exploring perovskite-based catalysts. However, such hybrids have not been achieved experimentally yet, mainly due to the weak interaction between the metal atom and the CsPbX3surface. Here, we demonstrate that Pt single atoms can be deposited on CsPbBr3NCs through a photoassisted approach, in which the surface was partially oxidized first, followed by the anchoring of Pt single atoms through the formation of Pt–O and Pt–Br bonds. The deposition of Pt single atoms can significantly change the photophysical properties of CsPbBr3NCs by inducing the generation of deep trap states in the band gap. The as-prepared Pt-SA/CsPbBr3can be used as efficient and durable catalysts for photocatalytic semi-hydrogenation of propyne. A CsPbBr3nanocrystal might be a suitable substrate for anchoring other metal single atoms, such as Cu, Au, Ag, Pd, and so on.

An efficient and robust in situsurface-confined strategy was demonstrated for the fabrication of single-atom Fe-N4on N-doped carbon nanoleaves (L-FeNC). Benefiting from abundant Fe-N4active sites, enhanced mass and charge transfer, L-FeNC delivered superior performance for ORR and Zn-air battery to commercial Pt/C.

Developing efficient Pt-based electrocatalysts for the methanol oxidation reaction (MOR) is of pivotal importance for large-scale application of direct methanol fuel cells (DMFCs), but Pt suffers from severe deactivation brought by the carbonaceous intermediates such as CO. Here, we demonstrate the formation of a bismuth oxyhydroxide (BiOx(OH)y)-Pt inverse interface via electrochemical reconstruction for enhanced methanol oxidation. By combining density functional theory calculations, X-ray absorption spectroscopy, ambient pressure X-ray photoelectron spectroscopy, and electrochemical characterizations, we reveal that the BiOx(OH)y-Pt inverse interface can induce the electron deficiency of neighboring Pt; this would result in weakened CO adsorption and strengthened OH adsorption, thereby facilitating the removal of the poisonous intermediates and ensuring the high activity and good stability of Pt2Bi sample. This work provides a comprehensive understanding of the inverse interface structure and deep insight into the active sites for MOR, offering great opportunities for rational fabrication of efficient electrocatalysts for DMFCs.

Single atom catalysts (SACs) have recently attracted great attention in heterogeneous catalysis and have been regarded as ideal models for investigating the strong interaction between metal and support. Despite the huge progress over the past decade, the deep understanding on the structure-performance correlation of SACs at a single atom level still remains to be a great challenge. In this study, we demonstrate that the variation in the coordination number of the Pt single atom can significantly promote the propylene selectivity during propyne semihydrogenation (PSH) for the first time. Specifically, the propylene selectivity greatly increases from 65.4% to 94.1% as the coordination number of Pt–O increases from ∼3.4 to ∼5, whereas the variation in the coordination number of Pt–O slightly influences the turnover frequency values of SACs. We anticipate that the present work may deepen the understanding on the structure-performance of SACs and also promote the fundamental research in single atom catalysis.

A series of novel CdS/CdIn2S4composite materials were prepared via a one-pot solvothermal process. The as-obtained photocatalysts were characterized by several techniques and the photocatalytic properties of CdS/CdIn2S4photocatalysts were studied by photocascade synthesis of Schiff base compounds in a photocatalytic reaction system of aromatic alcohols and nitrobenzene irradiated with visible light. The results reveal that the resulting CdS/CdIn2S4heterostructure samples show outstanding photocatalytic activities toward the photocascade production of Schiff base compounds in an aromatic alcohols and nitrobenzene reaction system irradiated with visible light. An optimized 50.0% CdS/CdIn2S4heterostructure sample shows the highest Schiff base yield of 42.0% irradiated with visible light for 4 h, which is approximately 19.1 and 1.54 times higher than those of sole CdS and CdIn2S4samples, respectively. The fabrication of heterogeneous structure improves the spatial separation and migration of photoinduced electron–hole pairs, thus contributing to the enhancement of photocatalytic properties. We foresee that this finding can offer a strategy to develop heterostructure composites for efficient synthesis of organics by photocatalysis under mild conditions.

Inherited factors contribute to lung cancer risk, but the mechanism is not well understood. Defining the biological consequence of GWAS hits in cancers is a promising strategy to elucidate the inherited mechanisms of cancers. The tag-SNP rs753955 (A>G) in 13q12.12 is highly associated with lung cancer risk in the Chinese population. Here, we systematically investigate the biological significance and the underlying mechanism behind 13q12.12 risk locus in vitro and in vivo. We characterize a novel p53-responsive enhancer with lung tissue cell specificity in a 49-kb high linkage disequilibrium block of rs753955. This enhancer harbors 3 highly linked common inherited variations (rs17336602, rs4770489, and rs34354770) and six p53 binding sequences either close to or located between the variations. The enhancer effectively protects normal lung cell lines against pulmonary carcinogen NNK-induced DNA damages and malignant transformation by upregulating TNFRSF19 through chromatin looping. These variations significantly weaken the enhancer activity by affecting its p53 response, especially when cells are exposed to NNK. The effect of the mutant enhancer alleles on TNFRSF19 target gene in vivo is supported by expression quantitative trait loci analysis of 117 Chinese NSCLC samples and GTEx data. Differentiated expression of TNFRSF19 and its statistical significant correlation with tumor TNM staging and patient survival indicate a suppressor role of TNFRSF19 in lung cancer. This study provides evidence of how the inherited variations in 13q12.12 contribute to lung cancer risk, highlighting the protective roles of the p53-responsive enhancer-mediated TNFRSF19 activation in lung cells under carcinogen stress.

Phase change materials, changing from solid to liquid and vice versa, are capable of storing and releasing a large amount of thermal energy during the phase change, and thus hold promise for numerous applications including thermal protection of electronic devices. Shaping these materials into microspheres for additional fascinating properties is efficient but challenging. In this regard, a novel phase change microsphere with the design for electrical-regulation and thermal storage/release properties was fabricated via the combination of monodispersed graphene aerogel microsphere (GAM) and phase change paraffin. A programmable method, i.e., coupling ink jetting–liquid marbling–supercritical drying (ILS) techniques, was demonstrated to produce monodispersed graphene aerogel microspheres (GAMs) with precise size-control. The resulting GAMs showed ultralow density, low electrical resistance, and high specific surface area with only ca. 5% diameter variation coefficient, and exhibited promising performance in smart switches. The phase change microspheres were obtained by capillary filling of phase change paraffin inside the GAMs and exhibited excellent properties, such as low electrical resistance, high latent heat, well sphericity, and thermal buffering. Assembling the phase change microsphere into the microcircuit, we found that this tiny device was quite sensitive and could respond to heat as low as 0.027 J.

Nowadays, the development of novel metallic materials for rock support have attracted research interests since they can significantly improve the deformation and energy absorption capacities of rock bolts. Although previous studies proved the importance and mechanical advantages of utilizing high-strength and high-toughness (HSHT) steels in rock support, there is no systematic analysis to reveal the essential energy absorption parameter and the guidelines for further development of metallic rock support materials. This paper analyzes the energy absorption characteristics of novel HSHT steels (negative Poisson's ratio (NPR) and twinning-induced plasticity (TWIP) steels) in comparison with conventional rock support materials. A physically based crystal plasticity (CP) model was set up and calibrated to study the effect of strain hardening rate (SHR). Meanwhile, the roles of underlying physical mechanisms, i.e. the dislocation density and twin volume fraction, were studied. The results show that the improvement of energy absorption density (EAD) is essential for further development of rock support materials, besides the increase of energy absorption rate (EAR) for previous development of conventional rock support materials. The increase of EAD requires increases of both strength and deformation capacity of materials. For HSHT steels, the decrease of SHR has a positive effect on the improvement of EAD. In addition, the increase of EAD is followed by the increase of twin volume fraction and the decrease of plastic Poisson's ratio which can promote deformation plasticity of materials. Meanwhile, the increase of EAR is correlated with the accumulation of dislocation density, which can increase the strength of materials. This paper provides the theoretical basis and guidelines for developing rock support materials in deep underground engineering and other related fields.

Building a reliable relationship between the electronic structure of alloyed metallic catalysts and catalytic performance is important but remains challenging due to the interference from many entangled factors. Herein, a PdBi surface alloy structural model, by tuning the deposition rate of Bi atoms relative to the atomic interdiffusion rate at the interface, realizes a continuous modulation of the electronic structure of Pd. Using advanced X-ray characterization techniques, we provide a precise depiction of the electronic structure of the PdBi surface alloy. As a result, the PdBi catalysts show enhanced propene selectivity compared with the pure Pd catalyst in the selective hydrogenation of propyne. The prevented formation of saturated β-hydrides in the subsurface layers and weakened propene adsorption on the surface contribute to the high selectivity. Our work provides in-depth understanding of the electronic properties of surface alloy structure and underlies the study of the electronic structure–performance relationship in bimetallic catalysts.

A Co-containing zeolitic imidazolate framework (ZIF-67) and ordered macroporous carbon (OMC) composite has been made via in situ growing ZIF-67 in the suspension of OMC. Different sizes of ZIF67-OMC-x (400, 700, 1000 nm) hybrid composites were synthesis by adding different amount of polyvinyl pyrrolidone (PVP). The SEM and TEM images demonstrated that the sizes of ZIF-67 matched well with the macropores of the OMC matrix in as-prepared ZIF67-OMC-400 nm composites. The intriguing structure of ZIF67-OMC-400 hybrid composites utilized synergistic interactions between the large surface area and ordered porosity structure of ZIF-67 and the high conductivity of OMC. More importantly, ZIF67-OMC-400 was explored as a novel modifying material for fabricating electrochemical sensor and then was utilized successfully for catechol (CC) and hydroquinone (HQ) simultaneous detection. Under the optimized condition, wide linear responses of this sensor were obtained for HQ and CC detection in the range of 0.1 μM to 100 μM. The modified electrode was successfully demonstrated for real samples such as river water with satisfactory results.