Synchronous Evolution Research Articles

Magnetic-field modulation of topological electronic state and emergent magneto-transport in a magnetic Weyl semimetal

The modulation of topological electronic state by an external magnetic field is highly desired for condensed-matter physics. Schemes to achieve this have been proposed theoretically, but few can be realized experimentally. Here, combining transverse transport, theoretical calculations, and scanning tunneling microscopy/spectroscopy (STM/S) investigations, we provide an observation that the topological electronic state, accompanied by an emergent magneto-transport phenomenon, was modulated by applying magnetic field through induced non-collinear magnetism in the magnetic Weyl semimetal EuB6. A giant unconventional anomalous Hall effect (UAHE) is found during the magnetization re-orientation from easy axes to hard ones in magnetic field, with a UAHE peak around the low field of 5 kOe. Under the reasonable spin-canting effect, the folding of the topological anti-crossing bands occurs, generating a strong Berry curvature that accounts for the observed UAHE. Field-dependent STM/S reveals a highly synchronous evolution of electronic density of states, with a dI/dV peak around the same field of 5 kOe, which provides evidence to the folded bands and excited UAHE by external magnetic fields. This finding elucidates the connection between the real-space non-collinear magnetism and the k-space topological electronic state and establishes a novel manner to engineer the magneto-transport behaviors of correlated electrons for future topological spintronics.

Holocene synchronous evolution of precipitation and soil moisture as evidenced by paleosol deposits in the Ili Basin, Central Asia

Assessing the impact of precipitation and temperature on soil moisture changes during the Holocene is essential to understanding the regional ecological environment change in the arid Central Asia core (CAC). However, this assessment is challenging due to the lack of reliable precipitation records. Here, we present Holocene paired precipitation and soil moisture records from the same paleosol deposits with well-constrained optically stimulated luminescence chronology in the Ili Basin, CAC. We selected dolomite content and the δ13C of organic matter to reflect precipitation change, and redness, frequency-dependent magnetic susceptibility, and total organic content to reflect soil moisture changes. The results show that precipitation and soil moisture records exhibit internal consistency, suggesting a synchronous evolution in both during the Holocene. We deduced that precipitation dominated Holocene soil moisture variations in the CAC. The increasing precipitation during the Holocene in the CAC may be attributed to the southward migration of the midlatitude westerlies and increasing penetration of water vapor from the Asian monsoon region.

Data-driven change control design for product and supply chain synchronous evolution systems under cyber-attacks

A product and supply chain synchronous evolution system (PSCSES) is a kind of complex distributed cyber-physical system (CPS), which contains several unmodeled dynamics and uncertainties, and the system structure and parameters are vulnerable to changes due to drastic demand fluctuations and unexpected network events. Thus, a product design change is an important way to maintain the stability of the synchronous evolution system to meet customers' demands and ensure economic efficiency. In this paper, the emergency change control problem of a distributed CPS-based PSCSES under DoS attacks is studied. First, an emergency change compensation mechanism in which a predictor based on recurrent neural networks is proposed to compensate for the lost inventory data caused by cyber-attacks. Second, the $H_{\infty}$ consensus control problem is transformed into a multiplayer zero-sum graph game using game theory, and a Q-learning-based $H_{\infty}$ consensus control protocol is designed, such that sufficient conditions that guarantee the consensus of the system can be derived. The bullwhip effects caused by the customers' demand and design change are analyzed thereby. Third, using the strategy iteration algorithm, the online solution is resolved for the controller design under the unknown model. Finally, the effectiveness of the proposed method is verified through the simulation of a collaborative production supply chain.

A collaborative scheduling model for production and transportation of ready-mixed concrete.

Ready-mixed-concrete (RMC) is an important green and clean building material which is widely used in modern civil engineering. For the large-scale planar foundations of urban public buildings, huge amounts of RMC need to be continuously delivered to the construction site according to strict time windows, which brings the problem of multi-plants collaborative supply. In this paper, considering transportation capacity, initial setting time, and interrupt pumping time, a collaborative scheduling model for production and transportation of RMC with the objective of minimizing the penalty cost of interruption pumping and vehicle waiting time and fuel consumption cost was established. According to the characteristics of the problem, a double chromosome synchronous evolution genetic algorithm was designed. Finally, the model and algorithm proposed in the paper were verified by data experiments. The computing results showed that in two cases of different scenarios, such as ordinary constructions and emergency constructions, the proposed scheduling model can save 18.6 and 24.8% cost respectively. The scheduling model and algorithm proposed in the paper can be applied directly to improve the operational efficiency of RMC supply chain.

Immunogenetic losses co-occurred with seahorse male pregnancy and mutation in tlx1 accompanied functional asplenia.

In the highly derived syngnathid fishes (pipefishes, seadragons & seahorses), the evolution of sex-role reversed brooding behavior culminated in the seahorse lineage's male pregnancy, whose males feature a specialized brood pouch into which females deposit eggs during mating. Then, eggs are intimately engulfed by a placenta-like tissue that facilitates gas and nutrient exchange. As fathers immunologically tolerate allogenic embryos, it was suggested that male pregnancy co-evolved with specific immunological adaptations. Indeed, here we show that a specific amino-acid replacement in the tlx1 transcription factor is associated with seahorses' asplenia (loss of spleen, an organ central in the immune system), as confirmed by a CRISPR-Cas9 experiment using zebrafish. Comparative genomics across the syngnathid phylogeny revealed that the complexity of the immune system gene repertoire decreases as parental care intensity increases. The synchronous evolution of immunogenetic alterations and male pregnancy supports the notion that male pregnancy co-evolved with the immunological tolerance of the embryo.

Trends and rhythms in carbonatites and kimberlites reflect thermo-tectonic evolution of Earth

Abstract Earth's thermo-tectonic evolution determines the way the planet's interior and surface interact and shows temporal changes in both trends and periodic rhythms. By sampling the subcontinental lithospheric mantle that represents the interface between the convecting mantle and the crust, carbonatite and kimberlite should be ideal rock types for documenting this evolution. The first-order secular rise of kimberlites over time has been noted by researchers, but there is much debate over how to interpret this trend, and their second-order variability has received less attention. We compiled a comprehensive global carbonatite database and compared it with an existing kimberlite one. We find that the numbers of carbonatites and kimberlites have similar increasing secular trends, with accelerated growth after ca. 1 Ga, and show the same periodic rhythms that have been synchronized to the supercontinent cycle since ca. 2.1 Ga. We link these trends and rhythms to the long-term change of Earth and the supercontinent cycle, both of which have altered the temperature of, and the subduction-recycled volatile flux into, the subcontinental lithosphere. Such consistent records in carbonatite and kimberlite behavior provide critical evidence for the synchronous thermo-tectonic evolution of the entire subcontinental lithosphere.

Efficient electrocatalytic desulfuration and synchronous hydrogen evolution from H2S via anti-sulfuretted NiSe nanowire array catalyst

Decreasing energy consumption of water splitting strategy by replacing oxygen evolution reaction (OER) with more facile sulfide oxidation reaction (SOR) to H2 evolution and value-added sulfur products is a promising technology. Nevertheless, the unsatisfactory catalyst long-term stability and passivation issues substantially limit the overall productivity. Herein, we report an anti-sulfuretted NiSe nanowire array catalyst on nickel foam (NiSe/NF), this catalyst exhibits a significantly reduced anode potential of 0.49 V vs. RHE at 100 mA cm−2 compared to the oxygen evolution reaction (1.78 V vs. RHE) and remains admirable stability for more than 500 h without passivation. Particularly, the skillful combination of UV–vis, in situ Raman, and attenuated total reflection Fourier transform infrared spectra, we reveal that S2-/HS- has been selectively converted to Sn2- and by-product S2O32- rather than sulfur, which avoids long-perplexing passivation issue of solid sulfur. For the first time, we demonstrate the feasibility of the system (SOR + HER) in a commercial membrane electrode assembly stack, which affords 19.0 mL min−1 H2 at a low cell voltage of 1.0 V with consuming the electricity of 2.63 kWh Nm−3 H2. This work provides a new avenue for low-cost H2 production by H2S electrooxidation desulfurization.

A Wasserstein generative digital twin model in health monitoring of rotating machines

Artificial intelligence-based rotating machine health monitoring and diagnosis methods often encounter problems, such as a lack of faulty samples. Although the simulation-based digital twin model may potentially alleviate these problems with sufficient prior knowledge and a large amount of time, the more demanding requirements of adaptivity, autonomy, and context-awareness may not be satisfied. This study attempted to address these problems by proposing a novel digital twin model referred to as the Wasserstein generative digital twin model (WGDT). The model employs a Wasserstein generative adversarial network (WGAN) as its core to model virtual samples with high fidelity to the healthy physical samples obtained from different industrial assets, thereby meeting the adaptivity requirement. Further, through a designed consistency test criterion mechanism, samples with high fidelity were generated by checking the similarity of distributions between generated samples and healthy physical samples to ensure that training process in conducted in a timely manner and manual involvement is avoided, thereby catering to the need for autonomy. This mechanism is based on the synchronous evolution of the generator and critic during training. Furthermore, the structure of the critic network can be customized according to the service-end tasks and testing conditions, thereby fulfilling the context awareness requirement. Subsequently, the critic network in the Wasserstein generative adversarial network (WGAN) can be used to perform different service-end tasks. The performance of the digital twin model was evaluated using two experimental cases and the results indicated that the WGDT model can efficiently and stably perform service-end tasks such as health monitoring, early fault detection, and degradation tracking without the requirement of prior knowledge, historical test samples, and faulty samples regarding the asset.

S-scheme N-doped carbon dots anchored g-C3N4/Fe2O3 shell/core composite for photoelectrocatalytic trimethoprim degradation and water splitting

Photoelectrocatalysis is a promising technique for energy conversion and environmental treatment. This study describes the photoelectrochemical (PEC) degradation of trimethoprim and hydrogen evolution using a photoanode prepared by N-doped carbon dots (NCD) incorporated g-C3N4/α-Fe2O3 (CNFO) shell/core nanocomposite. The electrochemical analysis reveals that the photocurrent density of NCD@CNFO photoanode reached 3.07 mA cm−2 at 1.6 V vs. NHE, which is 4 and 15 times greater than that of CNFO and intact α-Fe2O3, respectively. In the presence of peroxymonosulfate (PMS), the NCD@CNFO photoanode enabled 95 % and 90 % of trimethoprim (TMP) degradation in aqueous solution and lake water, respectively. Hydrogen generation coupled with TMP degradation was also observed in the PEC system, where the H2 generation rate was 550 µmol cm−2 h−1. Both superoxide (•O2−) and hydroxyl (•OH) radicals played a significant role in the degradation of TMP. The achievements could be assigned to the excellent photoabsorption and electron transfer properties of NCD, which enhanced the PEC activity of CNFO by enabling the S-scheme heterojunction to reduce electron-hole recombination. Moreover, PMS served as a cathodic electron acceptor to improve the catalytic properties of NCD@CNFO photoanode, demonstrating its contribution to both water treatment and hydrogen production. Such superior efficiency offers great potential to develop a PEC system using carbon dots/semiconductor hybrid catalysts for antibiotic degradation and synchronous photocatalytic H2 evolution from wastewater, providing an alternative solution to environmental pollution and energy crisis issues.

A dual-functional integrated Ni5P4/g-C3N4 S-scheme heterojunction for high performance synchronous photocatalytic hydrogen evolution and multi-contaminant removal with a waste-to-energy conversion

With a goal of waste-to-energy conversion, herein we report synchronous hydrogen evolution and pollutant degradation via photocatalysis utilizing novel Ni5P4/g-C3N4 S-scheme (Step scheme) heterojunction. The 25 %Ni5P4/g-C3N4 (25NP/CN) sample generates 40.1 mmol g-1h-1hydrogen evolution and 94.4 % carbamazepine degradation simultaneously under visible light and anaerobic conditions. Furthermore, the hydrogen evolution with carbamazepine, bisphenol A, sulfamethoxazole and rhodamine B is manifolds higher than in water. From The in-situ XPS results confirm the S-scheme transfer between Ni5P4 and g-C3N4. The presence of Ni0@Ni5P4 where strong covalent interactions between Ni0 and Ni-P single layers on Ni5-P4 not only enhanced the visible absorption, charge transfer but also leads to hydrogen formation by H+ transfer via a cyclic intermediate in a co-ordinate complex of degradation intermediates with Ni. This route is in addition to obvious e-/H+. The CBZ degradation and hydrogen evolution in aerobic/oxic conditions was also studied and 25NP/CN performs well under this atmosphere, inferring that oxidised intermediates act as electron donors and maintains the H2 evolution in longer run too. The photogenerated holes directly oxidized the pollutant in addition to OH radicals in anoxic medium and separated/accumulated electrons leads to hydrogen evolution. The scavenging experiments reveal that photogenerated holes directly oxidized the pollutant in addition to OH radicals in anoxic medium and separated/accumulated high potential electrons (via S-scheme transfer) leads to hydrogen evolution. The clean energy production and pollutant mineralization are synchronously achieved. Henceforth, a waste-to-energy route is proposed by coupling photocatalytic hydrogen evolution to environmental restoration.

18F-Choline PET/CT or PET/MR and the evaluation of response to systemic therapy in prostate cancer: are we ready?

PurposeDuring the last decade, [18F]F-choline positron emission tomography (PET) had a rising role in prostate cancer (PCa) imaging. However, despite auspicious premises, [18F]F-choline PET is not currently recommended for the evaluation of response to therapy assessment in PCa, mainly due to the lack of large-scale prospective trials.MethodsWe report the cases of seven patients affected by PCa, in which [18F]F-choline PET (either with computed tomography—CT or magnetic resonance imaging—MR) contributed significantly in the systemic therapy response evaluation.Results and conclusion[18F]F-choline PET/CT or PET/MR demonstrated to be a useful imaging modality in the assessment of response to systemic therapy in metastatic PCa patients, irrespective of the stage of disease (either in hormone sensitive and in castrate resistant condition) and the kind of systemic treatment. In most cases, PSA serum values and [18F]F-choline PET showed a synchronous disease evolution after systemic therapy. ADT can alter [18F]F-choline uptake, therefore the time of scan should be correctly planned. Finally, PET/CT with [18F]F-choline is a useful tool for reinforcing the identification of metastatic disease in case of a switch from metastatic castration sensitive to castration resistant PCa.

Synchronization patterns in the European Union

ABSTRACT In this paper, we quantify business cycles synchronization in the European Union by combining Principal Component Analysis (PCA) with a Random Matrix Theory (RMT) model. We employ a balanced panel of industrial production indexes over the 2000–2017 period and we track the evolution of the European synchronization, as measured by the largest and statistically significant principal component. Using the information contained in the eigenvector associated to it, we then identify the dynamics of synchronization clusters. Our results suggest that the degree of synchronization has increased since the introduction of the common currency and until the Great Recession, but decreased thereafter. In addition, our results point to the evolution of synchronization clusters over the past decades. Whereas western and eastern countries had divergent business cycles at the beginning of the 21st century, they have become more synchronized over the analysed period. However, since the dawn of the European sovereign debt crisis, the synchronization divide has become more apparent between northern and southern economies.

Late Holocene interaction of natural processes and human activity at two archaeological sites in the Ten Thousand Islands area of southwest Florida, USA

AbstractPalaeoenvironmental analysis of Late Holocene stratigraphic sequences recovered from two southwest Florida archaeological sites reveal a synchronous evolution of events caused by natural processes (e.g. sea‐level rise) and human activity (e.g. construction of shell works). Basal mangrove peats indicate that a transition from a terrestrial to coastal landscape started ~4000 cal bp in conjunction with the Late Holocene sea‐level rise. Continued sea‐level rise ultimately submerged the area to create estuarine conditions. Commensurate with submergence was the construction of relatively large (0.5 to 1.0 km2) shell mounds from 1500 to 1050 cal bp. These activities started in the estuarine environment and over time produced emergent landscape features with significant local relief (>7 m). The overlap in radiocarbon ages of oysters collected from the estuarine interval and the overlying shell mounds suggests construction material was locally harvested. About 1120 cal bp and during the waning of an indigenous presence in the area, red mangrove forests re‐emerged along the margins of each site and within the adjacent estuary to create an expansive mangrove‐dominated landscape within which both shell works are now embedded. This palaeoenvironmental reconstruction contradicts the prevailing notion that the two sites were purposely constructed on the mainland and adjacent to tidally influenced rivulets.

Construction and preparation of coated Z-scheme NaGdF4:Nd3+,Yb3+,Tm3+@CdS-Pd@NiO photocatalyst with core-shell structure for organic pollutant degradation with synchronous hydrogen evolution

A coated Z-scheme NaGdF4:Nd3+,Yb3+,Tm3+@CdS-Pd@NiO photocatalyst with core-shell structure is prepared by hydrothermal and coprecipitation methods. NaGdF4:Nd3+,Yb3+,Tm3+ as excellent up-conversion luminescent material can convert infrared light into visible light, broadening the light response range of CdS. Pd nanorods act as conductive channels and co-catalysts, leading to successful construction of titled photocatalyst, increasing contact area between two monomer photocatalysts, promoting transfer of photo-generated electrons. It also provides a large oxidation surface for organic pollutant degradation. The performance of prepared photocatalyst is assessed by Congo red degradation and hydrogen production. The emission spectrum and energy conversion mechanism of NaGdF4:Nd3+,Yb3+,Tm3+ are investigated. The photocatalyst with 3:1 NaGdF4:Nd3+,Yb3+,Tm3+@CdS-Pd and NiO mass ratio has a preeminent activity. Congo red degradation ratio and hydrogen production amount reach 92.48% and 653.06 µmol/g, respectively, under simulated sunlight irradiation for 180 min. The possible mechanism of organic pollutant degradation with synchronous hydrogen production caused by titled photocatalyst is proposed.

Common and idiosyncratic components of Latin American business cycles connectedness

ABSTRACT This paper investigates the evolution of business cycles synchronization in Latin America since the 1990ʹs. To do so, a Vector Autoregressive model is fed, alternatively, with the countries’ Industrial Production Indexes and with these series filtered by the US financial conditions index, which is considered a common component affecting business cycles in the region. Additionally, a Markov switching model is estimated to identify regional recessions. Our findings indicate that business cycles connectedness rise significantly during regional recessions and that the common factor plays an important role. The evidence supports the usefulness of policy coordination among Latin American economies to cushion the spillover effects of exogenous shocks, and helps to identify subgroups of countries for which such coordination is recommendable.

Late Holocene environmental and hydro-climatic variability inferred from a shallow lake record, blowout dunes, Argentinian western Pampas, South America

The Pampas plains of southern South America were predominantly dry, eolian-shaped landscapes, besides some interposed humid phases, during most of the late Pleistocene-Middle Holocene, evolving to humid-subhumid grasslands hosting an increasingly large number of shallow lakes in the late Holocene. These lakes proved to preserve in their sediments worthy evidence to interpret past environmental-ecological conditions, offering tools to analyze climatic variability and human impacts during the last millennia. This is the case of the shallow lake Primera Laguna, located in the western and driest edge of the Pampas. Here, we present a multiproxy study from this shallow lake with the aims of contributing to reconstruct its past stages, infer the climatic scenarios that drove its evolution, evaluate the potential anthropogenic role in these changes, and correlate/analyze this record with available data from other Pampean lakes. We analyzed a high-resolution palynological record, accompanied by macroscopic charcoal accumulation rates, C/N, C and N stable isotopes, magnetic susceptibility, and sediment geochemistry, of a 41-cm long sediment core, extracted from the deepest sector of the lake. An age-depth model based on AMS chronology indicates a preserved lake history for the past ∼1400 cal yr BP. Ecological and sedimentological interpretations allowed us to propose four main periods during this time lapse. For the first period (1375–1069 cal yr BP, 575–881 CE), the integrative interpretation indicates a very low shallow lake –mostly oligotrophic, alkaline, and clear water–, dominated by the accumulation of epiclastic silty fine sand from the surrounded eolian landscape and covered by xerophytic vegetation. In the second period, between 1069 and 738 cal yr BP (881–1212 CE), we inferred a trend to rising lake levels and mesotrophic conditions, and more pollen taxa than the previous period, and with lake margins dominated by cattails and sedges. The third period (738–193 cal yr BP, 1212–1757 CE) was characterized by more variable and lower lake levels compared to previous periods and more frequent desiccation processes at the lake margins. Then, during the fourth period (last 195 cal yr, 1757–2015 CE), there was a gradual transition towards a larger and more stable shallow lake with a deeper water column, and under a turbid state probably related to eutrophication. From the comparison between Primera Laguna record and the previously studied Nassau shallow lake, located in the same eolian landscape, we found a synchronic evolution, implying common drivers of change in terms of climatic variability and human impact. Correlation with shallow lakes from the more humid belt of the Pampas suggests widespread increases of water availability in the region since ∼1500 cal yr BP, variable/lower lake levels during ∼600–200 cal yr BP, and a shift to positive hydrological balances up to the present highstands.

A new strategy for fabrication of unique heterostructured titanium laminates and visually tracking their synchronous evolution of strain partitions versus microstructure

• A new strategy for producing Ti laminates with gradient structure (GS) and heterogeneous lamella structure (HLS) is proposed. • Strain partitions versus microstructure evolution is visualized synchronously using ultrahigh-resolution SEM-DIC combined with EBSD. • GS/HLS Ti exhibited a superior combination of strength and ductility, which is attributed to HDI stress strengthening and HDI hardening. Heterostructured (HS) material with extraordinary mechanical properties has been regarded as one of the most promising structural materials. Here, we reported a new strategy for preparing heterostructured pure titanium laminates that possess a good combination of strength and ductility by combining gradient structure (GS) and heterogeneous lamella structure (HLS). The deformation characteristic versus microstructure evolution of GS/HLS titanium laminates, namely the strain partitions between different-sized grains (480–25 μm) was visualized using a scanning electron microscope (SEM) equipped with electron backscattered diffraction (EBSD) mode combined with the digital image correlation (SEM-DIC) with an ultrahigh spatial resolution for the first time. As a result, the hetero-deformation of unique GS/HLS structure by the characteristic of strain partitions could be accurately captured. While the hetero-deformation could result in the hetero-deformation induced (HDI) stress strengthening and HDI hardening, which were regarded as the key reason that the resulting GS/HLS Ti laminates showed a superior combination of strength and ductility. This could promote a more in-depth understanding of the strengthening-toughening mechanism of heterostructured material.

EarlyCretaceous‐Cenozoicexhumation history of Luxi Terrane and adjacent areas, eastern North China Craton

The Luxi Terrane is important for understanding the large‐scale extension and lithospheric thinning in eastern North China Craton (NCC) during the Mesozoic to Cenozoic. However, the exhumation/uplift history of the whole region in comparison to its adjacent areas is still unclear. To address this issue, we compiled 892 thermochronological data using jointly Kernel density estimation and linear inversion approaches to identify the exhumation episodes and estimate the temporal and spatial variation of the exhumation rates. The results indicated that these areas all experienced three rapid exhumation episodes, throughout the Early Cretaceous (120–100 Ma), Late Cretaceous‐Palaeocene (90–60 Ma), and Eocene (50–35 Ma). While the existence of synchronous tectonic evolution, the exhumation rates are heterogeneously distributed throughout the Luxi Terrane and neighbouring areas in space and time. We suggest that tectonics may play a role in setting up the regional variation in exhumation patterns. Considering the plate reconstructions and integrating low‐temperature thermochronological studies, the Early Cretaceous rapid exhumation corresponds to extensive craton destruction, linked with the Izanagi slab rollback within a back‐arc extensional setting. The Late Cretaceous‐Palaeocene rapid exhumation is interpreted as a response to continuing craton destruction and lithospheric thinning resulting from the subduction of Izanagi‐Pacific. In the Eocene, we propose that the coupling effect of subduction of Pacific Plate and India‐Eurasia collision can trigger this cooling episode.

Fabrication of novel immobilized and forced Z-scheme Ag|AgNbO3/Ag/Er3+:YAlO3@Nb2O5 nanocomposite film photocatalyst for enhanced degradation of auramine O with synchronous evolution of pure hydrogen

An immobilized and forced Z-scheme Ag|AgNbO3/Ag/Er3+:YAlO3@Nb2O5 nanocomposite film photocatalyst is prepared via sol–gel spin coating and photoreduction technologies, and applied in solar photocatalytic removal of auramine O and synchronous evolution of pure hydrogen. An immobilized reactor with the nanocomposite film is designed to realize the photocatalytic oxidation and reduction on both sides of the Ag foil as carrier, respectively. The mechanism on the immobilized and forced Z-scheme Ag|AgNbO3/Ag/Er3+:YAlO3@Nb2O5 photocatalytic system is proposed. The results indicate that pure hydrogen can be directly produced on the surface of the Ag foil. The 318.37 μmol pure hydrogen can be collected at 84.90 mmol/h·m2, and 92.72 % degradation of 10 mg/L auramine O can be obtained under 180 min sunlight irradiation. Ag|AgNbO3/Ag/Er3+:YAlO3@Nb2O5 nanocomposite film also possesses high recycling capacity. This photocatalytic technology performs good application prospects in organic wastewater purification and hydrogen energy development.

A 3D C@TiO2 multishell nanoframe for simultaneous photothermal catalytic hydrogen generation and organic pollutant degradation

Rapid heat loss and fast charge carrier recombination constitute two crucial issues that hinder the development of efficient solar energy utilization and conversion over the semiconductor in a photothermal catalytic system. Inspired by energy production from waste water, we designed an advanced 3D C@TiO2 multishell nanoframe (MNF) photocatalyst. Its unique structural features of heat confinement and vibrant photocarrier kinetics lead to excellent photo-thermal conversion for synchronous superior photocatalytic H2 evolution (503 μmol g-1h−1) and 98.2% RhB removal without the use of any co-catalyst and sacrificial reagent under simulated sunlight irradiation (AM 1.5G). Mechanism exploration reveals that the difference between the inner and outer gas pressure formed inside C@TiO2 precursor facilitates the selective cleavage of outer TiO2 layers at selected temperatures during calcination. Synergistic effects between residual carbon core and multi-shelled TiO2 framework endow C@TiO2 MNF with excellent heat confinement and vibrant photocarrier kinetics. Such MNF photo-thermocatalyst concept provides a novel strategy for effective utilization of solar energy, and this work may open a novel avenue towards advanced nanostructures for efficient waste-to-energy conversion.