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[Display omitted] • Cr dopant promotes the in situ reconstruction of Ni 3 N during HER and OER. • Cr-doping enhances OH– adsorption and boosts the formation of NiOOH. • Cr dopant facilitates the H 2 O activation and the generation of Ni 3 N/Ni(OH) 2. • Cr-Ni 3 N/NF displays high OER and HER activities along with good stability. • It gives a small voltage of 1.72 V at 100 mA cm−2 in overall water splitting. Understanding and utilizing the dynamic changes of electrocatalysts under working conditions are important for advancing the sustainable hydrogen production. Here, we for the first time report that Cr-doping can promote the in situ reconstruction of a self-supported Ni 3 N electrocatalyst (Cr-Ni 3 N/NF) during oxygen and hydrogen evolution reactions (OER and HER), and therefore improve the electrocatalytic water splitting performance. As identified by in situ measurements and theoretical calculations, Cr-doping enhances OH– adsorption during OER at anode and thereby boosts the transformation of Ni 3 N pre-catalysts to defect-rich nickel oxyhydroxide (NiOOH) active species. Meanwhile, it facilitates the generation of Ni 3 N/Ni(OH) 2 at cathodes due to effective H 2 O activation, leading to the fast HER kinetics on the Ni 3 N/Ni(OH) 2 interfaces. Notably, the optimal Cr-Ni 3 N/NF displays good OER and HER performance in 1.0 M KOH electrolytes, with low overpotentials of 316 and 188 mV to achieve the current density of ± 100 mA cm−2, respectively. Benefiting from its bi-functionality and self-supporting property, an alkaline electrolyzer equipped with Cr-Ni 3 N/NF as both anode and cathode affords a small voltage of 1.72 V at 100 mA cm−2, along with 100 h operation stability. Elucidating that Cr-doping can boost in situ reconfiguration and consequently the electrocatalytic activity, this work would shed new light on the rational design and synthesis of electrocatalysts via directional reconstructions. [ABSTRACT FROM AUTHOR]

A carefully designed C and S co doped Co 2 VO 4 /CoP heterojunction strategy was constructed using a synergistic approach of hydrothermal and vapor deposition. This strategy requires the synergistic improvement of thermodynamic performance by adjusting electronic structure and nanoscale kinetic improvements, resulting in efficient dual functionality for seawater decomposition. [Display omitted] The endeavor to architect bifunctional electrocatalysts that exhibit both exceptional activity and durability heralds an era of boundless potential for the comprehensive electrolysis of seawater, an aspiration that, nevertheless, poses a substantial challenge. Within this work, we describe the precise engineering of a three-dimensional interconnected nanoparticle system named S C doped Co 2 VO 4 /CoP (S C Co 2 VO 4), achieved through a meticulously arranged hydrothermal treatment sequence followed by gas-phase carbonization and phosphorization. The resulting S C Co 2 VO 4 electrode exhibits outstanding bifunctional electrocatalytic stability, attributed to the strategic anionic doping and abundant heterogeneous interfaces. Doping not only adjusts the electronic structure, enhancing electron transfer efficiency but also optimizes the surface-active sites. This electrode prodigiously necessitated an extraordinarily minimal overpotential of merely 92 and 350 mV to attain current densities of 10 and 50 mA cm−2 for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, in 1 M KOH solution. Noteworthily, when integrated into an electrolyzer for the exhaustive splitting of seawater, the S C P-Co 2 VO 4 manifested an exceptionally low cell voltage of 2.08 V@50 mA cm−2 and showcased a durability that eclipses that of most hitherto documented nickel-based bifunctional materials. Further elucidation through Density Functional Theory (DFT) analyses underscored that anion doping and the inherent heterostructure adeptly optimize the Gibbs free energy of intermediates comprising hydrogen, chlorine, and oxygen (manifested as OH, O, OOH) within the HER and OER paradigms, thus propelling the electrochemical kinetics of seawater splitting to unprecedented velocities. These revelations unfurl a pioneering design philosophy for the creation of cost-effective yet superior catalysts aimed at the holistic division of water molecules, charting a course towards the realization of efficient and sustainable hydrogen production methodologies. [ABSTRACT FROM AUTHOR]

The oxide surface structure plays a vital role in controlling and utilizing the emergent phenomena occurring at the interface of nanoarchitecture. A complete understanding of ternary oxide surfaces remains challenging due to complex surface reconstructions in various chemical and physical environments. Here a thermodynamic framework is developed to treat the stability of ternary oxide surfaces with finite temperature and chemical environments. Strontium titanate, as a representative ternary oxide, is used to establish the complete energy landscape of SrTiO3 (001) surface. The complete mapping yields a comprehensive understanding of various stable SrTiO3 surfaces with finite temperature and chemical potential or vapor pressure of the constituents, i.e., Sr (or Ti) metal and oxygen. This treatment also reveals a stable surface unknown yet with SrTi2O3 stoichiometry, which unveils the missing link between numerous previous experimental observations and the current understanding of SrTiO3 surface. Interestingly, the new surface shows an anisotropic surface‐localized metallic state originating from the characteristic surface structure. The findings would provide a viable way to understand ternary oxide surfaces and further utilize SrTiO3 surfaces for oxide nanoarchitectures. [ABSTRACT FROM AUTHOR]

Efficiently reconstructing complex and intricate surfaces at scale remains a significant challenge in 3D surface reconstruction. Recently, implicit neural representations have become a popular topic in 3D surface reconstruction. However, how to handle loop closure and bundle adjustment is a tricky problem for neural methods, because they learn the neural parameters globally. We present an algorithm that leverages the concept of surfels and expands relevant definitions to address such challenges. By integrating neural descriptors with surfels and framing surfel association as a deformation graph optimization problem, our method is able to effectively perform loop closure detection and loop correction in challenging scenarios. Furthermore, the surfel-level representation simplifies the complexity of 3D neural reconstruction. Meanwhile, the binding of neural descriptors to corresponding surfels produces a dense volumetric signed distance function (SDF), enabling the mesh reconstruction. Our approach demonstrates a significant improvement in reconstruction accuracy, reducing the average error by 16.9% compared to previous methods, while also generating modeling files that are up to 90% smaller than those produced by traditional methods. [ABSTRACT FROM AUTHOR]

In this work, we propose an efficient smoothed particle hydrodynamics (SPH) method for simulating laser powder bed fusion (LPBF). The multi-physics process of LPBF, including the heat transfer and phase change with complex boundaries, is accurately resolved by a novel heat source model and a modified continuous surface force based on a corrected surface delta function. Moreover, we also develop an efficient tensile instability control algorithm for preventing the pressure oscillations. The present method is implemented in a GPU-accelerated framework, and its performance is well demonstrated by simulating the LPBF processes with both single-layer and multi-layer powder beds (with the help of surface reconstruction). The numerical results are compared well with the experimental ones which clearly verify the ability of the present method in capturing the complex physical phenomenon of LPBF. [ABSTRACT FROM AUTHOR]

Obstructed atomic insulator is recently proposed as an unconventional material, in which electric charge centers localized at sites away from the atoms. A half-filling surface state would emerge at specific interfaces cutting through these charge centers and avoid intersecting any atoms. In this article, we utilized photoemission spectroscopy and density functional theory calculations to study one of the obstructed atomic insulator candidates, NiP2. A floating surface state with large effective mass that is close to the Fermi level and isolated from all bulk states is resolved on the (100) cleavage plane, implying better catalytic activity in this plane than the previously studied surfaces. Density functional theory calculation results elucidate that this floating surface state is originated from the obstructed Wannier charge centers, albeit underwent surface reconstruction. Our findings not only shed lights on the study of obstructed atomic insulators, but also provide possible route for development of new catalysts. [ABSTRACT FROM AUTHOR]

The crystal structure of a novel MAX phase is determined using X-ray powder diffraction, spherical aberration corrected transmission electron microscopy, and first-principles calculations. In the new V–Sn–C system, the R 3 ‾ m space group aligns more closely with the experimental data than the P 6 3 /mmc space group. The lattice parameters of the new trigonal V 2 SnC phase are a = 0.291 nm and c = 2.08 nm. Moreover, the surface of the new phase has a tin-doped carbide face-centered cubic (FCC) structure reconstruction layer. First-principles calculations indicate that the new trigonal V 2 SnC phase is metastable compared with the hexagonal V 2 SnC phase. However, the thermal stability of the metastable trigonal V 2 SnC in air is significantly enhanced owing to the presence of the reconstruction layer. [ABSTRACT FROM AUTHOR]

The current limitations in utilizing metal-organic frameworks for (photo)electrochemical applications stem from their diminished electrochemical stability. In our study, we illustrate a method to bolster the activity and stability of (photo)electrocatalytically active metal-organic frameworks through ligand engineering. We synthesize four distinct mixed-ligand versions of zeolitic imidazolate framework-67, and conduct a comprehensive investigation into the structural evolution and self-reconstruction during electrocatalytic oxygen evolution reactions. In contrast to the conventional single-ligand ZIF, where the framework undergoes a complete transformation into CoOOH via a stepwise oxidation, the ligand-engineered zeolitic imidazolate frameworks manage to preserve the fundamental framework structure by in-situ forming a protective cobalt (oxy)hydroxide layer on the surface. This surface reconstruction facilitates both conductivity and catalytic activity by one order of magnitude and considerably enhances the (photo)electrochemical stability. This work highlights the vital role of ligand engineering for designing advanced and stable metal-organic frameworks for photo- and electrocatalysis. The application of metal-organic frameworks in (photo)electrocatalysis is constrained by their structural stability. Here, the authors report mixed-ligand zeolitic imidazolate frameworks that can in-situ form a protective (oxy)hydroxide layer through surface reconstruction, enhancing both catalytic activity and stability during (photo)electrocatalytic oxygen evolution reactions. [ABSTRACT FROM AUTHOR]

Silicon surface alloys and silicide nanolayers are highly important as contact materials in integrated circuit devices. Here we demonstrate that the submonolayer Si/Ag(001) surface reconstruction, reported to exhibit interesting topological properties, comprises a quasi-one-dimensional Si-Ag surface alloy based on chains of planar double-pentagon Si moieties. This geometry is determined using a combination of density functional theory calculations, scanning tunnelling microscopy, and grazing incidence x-ray diffraction simulations, and yields an electronic structure in excellent agreement with photoemission measurements. This work provides further evidence of pentagonal geometries in 2D materials and heterostructures and elucidates the importance of surface alloying in stabilizing their formation. Using DFT simulations and STM measurements, the Si/Ag(001) surface reconstruction is revealed to be a Si-Ag surface alloy. Its atomic structure is composed of quasi-1D double-pentagon chains of silicon, electronically isolated by surface Ag atoms. [ABSTRACT FROM AUTHOR]

Electrolyte plays crucial roles in electrochemical CO2 reduction reaction (e‐CO2RR), yet how it affects the e‐CO2RR performance still being unclarified. In this work, it is reported that Sn‐Zn hybrid oxide enables excellent CO2‐to‐HCOO− conversion in KHCO3 with a HCOO− Faraday efficiency ≈89%, a yield rate ≈0.58 mmol cm−2 h−1 and a stability up to ≈60 h at −0.93 V, which are higher than those in NaHCO3 and K2SO4. Systematical characterizations unveil that the surface reconstruction on Sn‐Zn greatly depends on the electrolyte using: the Sn‐SnO2/ZnO, the ZnO encapsulated Sn‐SnO2/ZnO and the Sn‐SnO2/Zn‐ZnO are reconstructed on the surface by KHCO3, NaHCO3 and K2SO4, respectively. The improved CO2‐to‐HCOO− performance in KHCO3 is highly attributed to the reconstructed Sn‐SnO2/ZnO, which can enhance the charge transportation, promote the CO2 adsorption and optimize the adsorption configuration, accumulate the protons by enhancing water adsorption/cleavage and limit the hydrogen evolution. The findings may provide insightful understanding on the relationship between electrolyte and surface reconstruction in e‐CO2RR and guide the design of novel electrocatalyst for effective CO2 reduction. [ABSTRACT FROM AUTHOR]

Reconstructing geometric shapes from sparse multiview has always been a challenging task. With the development of neural implicit surfaces, geometry‐based volume rendering surface reconstruction methods have been proven to be able to reconstruct high‐quality surfaces. However, existing geometry‐based reconstruction methods completely associate volume density with signed distance function or unsigned distance function, resulting in the same volume density peak that can only be reconstructed near the object surface. When there are transparent surfaces in the scene, existing methods prioritize the reconstruction of opaque surfaces, neglecting the reconstruction of transparent surfaces, which is disadvantageous when reconstructing real scenes. To solve this problem, we introduce local probability standard variance, which calculates volume density together with signed distance function. In this way, it can reconstruct the volume density that matches the transparency characteristics of the object surface. The method can reconstruct the surface of transparent objects, and experiments on two transparent surface datasets show that the method performs better. [ABSTRACT FROM AUTHOR]

[Display omitted] The cathodes of solid oxide fuel cells (SOFCs) often suffer from detrimental cation segregations and associated impurities poisoning, leading to insufficient electroactivity and poor stability. Here we developed a medium-entropy double perovskite GdBa(Co 1.2 Mn 0.2 Fe 0.2 Ni 0.2 Cu 0.2)O 5-δ (ME-GBCO) for promising SOFC cathode. The increased configuration entropy can effectively tailor the surface composition with in situ formed active BaCoO 3-δ (BCO) species, rather than inert and deleterious BaO x segregation on parent GdBaCo 2 O 5-δ (GBCO) surface. Accordingly, the layered ME-GBCO cathode with beneficial surface reconstruction exhibited not only high oxygen reduction activity but excellent durability against CO 2 impurity, enabling it a very attractive cathode for intermediate temperature SOFCs (IT-SOFCs). Our study provides a new idea for development of efficient and durable cathodes via configurational entropy induced rational surface reconstruction. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel core–shell Co 2 (PS 3)@Co 2 P is designed as a pre-catalyst. • The Co 2 (PS 3)@Co 2 P catalyst with fast surface reconstruction. • The PO 4 3−, SO 3 2− and SO 4 2−-decorated CoOOH as a true catalyst. • The oxyanions can enhance the activity and stability in seawater. • The oxyanions can optimize the intermediates' chemisorption. The design of pre-catalysts and the rational manipulation of corresponding electrochemical reconstruction are vitally important to construct the highly durable and active catalysts for seawater oxidation, but rather challenging. Herein, a novel core–shell catalyst of Co 2 (PS 3)@Co 2 P (labeled as CoPS) by epitaxial growth of amorphous cobalt phosphide (Co 2 P) on crystalline cobalt phosphorous trichalcogenide (Co 2 (PS 3)) is firstly designed as a pre-catalyst for alkaline seawater oxidation. Various characterization techniques are employed to demonstrate that the unique amorphous-crystalline nanowire structure (CoPS) achieves the rapid surface reconstruction into active CoOOH and diversiform oxyanions species (labeled as CoPS-R). Theoretical simulations uncover that the in situ derived oxyanions (PO 4 2−, SO 3 2− and SO 4 2−) on the surface of CoOOH can tune the electron distribution of Co site, thereby optimizing the chemisorption of oxygen evolution reaction (OER) intermediates on CoOOH and reducing the energy barrier of determining step. Consequently, in an alkaline natural seawater solution, the reconstructed CoPS-R catalyst exhibits small overpotentials of 357 and 402 mV for OER at 200 and 500 mA cm−2, respectively, together with an impressive durability over 500 h at a large current density of 500 mA cm−2 benefiting from the strong repulsive effect of the derived PO 4 2−, SO 3 2− and SO 4 2− oxyanions. This work offers a new insight for comprehending the relationship of structure-composition-activity and develops a new approach toward the construction of efficient and robust OER catalysts for seawater electrolysis. [ABSTRACT FROM AUTHOR]

[Display omitted] The sluggish kinetics and inferior stability of oxygen electrocatalyst in rechargeable zinc air battery (ZAB) hamper its industrialization. In this work, we activate cobalt telluride (CoTe) by introduction of metallic cobalt (Co) to modulate the work function to facilitate the electron transfer from Co to CoTe during oxygen catalysis; additionally, the three-dimensional porous carbon nanosheets (3DPC) are invited to reduce the resistance towards electrolyte/oxygen diffusion. Thereby, Co-CoTe@3DPC only demands 280 mV overpotential to reach 10 mA cm−2 under alkaline oxygen evolution reaction (OER) condition, relatively lower than commercial iridium oxides (IrO 2); besides, the operando electrochemical impedance spectroscopy (EIS) indicates a better resistance towards surface reconstruction than Co@3DPC leading to a superior stability. A Pt-like oxygen reduction reaction (ORR) performance, half-wave potential associated with kinetic current density, is achieved for Co-CoTe@3DPC. A maximum power density of 203 mW cm−2 is achieved and sustains for 800 h. Furthermore, the all-solid-state ZAB offers 97 mW cm−2. Theoretical calculation suggests that the incorporation of metallic Co to CoTe maintains the superb ORR activity and promotes the OER catalysis. [ABSTRACT FROM AUTHOR]

The most environmentally friendly method for producing hydrogen is through the electrolysis of water, reliable and effective catalysts play a crucial role in enhancing hydrogen production efficiency. In this paper, Fe–NiC 2 O 4 /NF in block form was prepared by hydrothermal method on nickel foam (NF) for electrolysis of water under alkaline conditions. The surface reconstruction of the Fe–NiC 2 O 4 /NF was further investigated via XRD, FTIR, and XPS during the oxygen evolution reaction (OER). The catalytic activity of Fe–Ni(OH) 2 /NiOOH formed after reconstruction was considerably enhanced in comparison to the original catalyst. The overpotentials for hydrogen evolution reaction (HER) at 10 mA cm−2 and OER at 100 mA cm−2 were 126 mV and 260 mV, respectively. Meanwhile, applying it in a two-electrode, total hydrolysis device only requires 1.53 V at 10 mA cm−2. This investigation introduces a novel method for surface reconstruction of electrocatalysts to facilitate electrolytic water reaction. [ABSTRACT FROM AUTHOR]

The excavation tunnel model is an important reference for mine equipment control and tunnel deformation monitoring. Currently, tunnel models are mainly created manually, and point cloud reconstruction algorithms are difficult to directly apply to tunnel point clouds. To address these issues, this paper proposes a point cloud-based excavation tunnel modeling method. First, preprocessing algorithms such as point cloud coordinate transformation, tunnel point cloud extraction, and tunnel point cloud completion are used to filter out equipment point clouds inside the tunnel and repair occluded holes. Then, the tunnel centerline is extracted, and consistency optimization is performed on the point cloud normal vectors. Finally, a tunnel model is established based on the Poisson modeling algorithm, enabling high-precision tunnel modeling. The proposed algorithm's accuracy and effectiveness are demonstrated through experiments on four different coal mine tunnels. [ABSTRACT FROM AUTHOR]

We study the transport properties of underdoped trilayer cuprate HgBa2Ca2Cu3O8+δ with doping level p = 0.10–0.12 in magnetic field up to 88 T. We report for the first time in a cuprate superconductor a dramatic change of the quantum oscillation spectrum versus temperature, which is accompanied by a sign change of the Hall effect below T ≈10 K. Based on numerical simulations, we infer a Fermi surface reconstruction in the inner plane from an antiferromagnetic state (hole pockets) to a biaxial charge density wave state (electron pockets). We show that both orders compete and share the same hotspots of the Fermi surface, and we discuss our result in the context of spin-fermion models. [ABSTRACT FROM AUTHOR]

In reconstructive surgery following partial mandibulectomy, the biomechanical integrity of the fibula free flap applied to the remaining mandibular region directly influences the prognosis of the surgery. The purpose of this study is to evaluate the biomechanical integrity of two fixation materials [titanium (Ti) and hydroxyapatite/poly-L-lactide (HA-PLLA)]. In this study, we simulated the mechanical properties of miniplate and screw fixations in two different systems by finite element analysis. A three-dimensional mandibular model was constructed and a fibula free flap and reconstruction surface were designed. The anterior and posterior end of the free flap was positioned with two miniplates and two additional miniplates were applied to the angled area of the fibula. The masticatory loading was applied considering seven principal muscles. The peak von Mises stress (PVMS) distribution, size of fixation deformation, principal stresses on bones, and gap opening size were measured to evaluate the material properties of the fixation. In the evaluation of properties, superior results were observed with both fixation methods immediately after surgery. However, after the formation of callus between bone segments at 2 months, the performance of Ti fixation decreased over time and the differences between the two fixations became minimal by 6 months after surgery. The result of the study implies the positive clinical potential of the HA-PLLA fixation system applied in fibula free flap reconstruction. [ABSTRACT FROM AUTHOR]

Laser point clouds are commonly affected by Gaussian and Laplace noise, resulting in decreased accuracy in subsequent surface reconstruction and visualization processes. However, existing point cloud denoising algorithms often overlook the local consistency and density of the point cloud normal vector. A feature map learning algorithm which integrates point normal constraints, Dirichlet energy, and coupled orthogonality bias terms is proposed. Specifically, the Dirichlet energy is employed to penalize the difference between neighboring normal vectors and combined with a coupled orthogonality bias term to enhance the orthogonality between the normal vectors and the subsurface, thereby enhancing the accuracy and robustness of the learned denoising of the feature maps. Additionally, to mitigate the effect of mixing noise, a point cloud density function is introduced to rapidly capture local feature correlations. In experimental findings on the anchor public dataset, the proposed method reduces the average mean square error (MSE) by 0.005 and 0.054 compared to the MRPCA and NLD algorithms, respectively. Moreover, it improves the average signal-to-noise ratio (SNR) by 0.13 DB and 2.14 DB compared to MRPCA and AWLOP, respectively. The proposed algorithm enhances computational efficiency by 27% compared to the RSLDM method. It not only removes mixed noise but also preserves the local geometric features of the point cloud, further improving computational efficiency. [ABSTRACT FROM AUTHOR]

The crystalline dependent discharge process shows strong structure-reforming ability on surface and promotes the formation of vacancies and thus reducing the adsorption energy of intermediate. [Display omitted] Alkaline water electrolysis is apreferred technology for large-scale green hydrogen production. For most active transition metal-based catalysts during anodic oxygen evolution reaction (OER), the atomic structure of the anodic catalysts' surface often undergoes reconstruction to optimize the reaction path and enhance their catalytic activity. The design and maintenance of highly active sites during this reconstruction process remain critical and challenging for most OER catalysts. In this study, we explored the effects of crystal structures in pre-catalysts on surface reconstruction at low applied potential. Through experimental observation and theoretical calculation, we found out that catalysts with specific crystal structures exhibit superior surface remodeling ability, which enables them to better adapt to the conditions of the oxygen evolution reaction and achieve efficient catalysis. The discharge process enables the formation of abundant phosphorus vacancies on the surface, which in turn affects the efficiency of the entire oxygen evolution reaction. The optimized crystal structure of the catalyst results in an increase as high as 58.5 mA/cm2 for Ni 5 P 4 , which is twice as high as that observed for Ni 2 P. These results provide essential theoretical foundations and technical guidance for designing more efficient catalysts for oxygen evolution reactions. [ABSTRACT FROM AUTHOR]

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Electricity-driven water splitting to produce hydrogen is one of the most efficient ways to alleviate energy crisis and environmental pollution problems, in which the anodic oxygen evolution reaction (OER) is the key half-reaction of performance-limiting in water splitting. Given the complicated reaction process and surface reconstruction of the involved catalysts under actual working conditions, unraveling the real active sites, probing multiple reaction intermediates and clarifying catalytic pathways through in-situ characterization techniques and theoretical calculations are essential. In this review, we summarize the recent advancements in understanding the catalytic process, unlocking the water oxidation active phase and elucidating catalytic mechanism of water oxidation by various in-situ characterization techniques. Firstly, we introduce conventionally proposed traditional catalytic mechanisms and novel evolutionary mechanisms of OER, and highlight the significance of optimal catalytic pathways and intrinsic stability. Next, we provide a comprehensive overview of the fundamental working principles, different detection modes, applicable scenarios, and limitations associated with the in-situ characterization techniques. Further, we exemplified the in-situ studies and discussed phase transition detection, visualization of speciation evolution, electronic structure tracking, observation of reaction active intermediates, and monitoring of catalytic products, as well as establishing catalytic structure--activity relationships and catalytic mechanism. Finally, the key challenges and future perspectives for demystifying the water oxidation process are briefly proposed. [ABSTRACT FROM AUTHOR]

Feature-preserving mesh reconstruction from point clouds is challenging. Implicit methods tend to fit smooth surfaces and cannot be used to reconstruct sharp features. Explicit reconstruction methods are sensitive to noise and only interpolate sharp features when points are distributed on feature lines. We propose a watertight surface reconstruction method based on optimal transport that can accurately reconstruct sharp features often present in CAD models. We formalize the surface reconstruction problem by minimizing the optimal transport cost between the point cloud and the reconstructed surface. The algorithm consists of initialization and refinement steps. In the initialization step, the convex hull of the point cloud is deformed under the guidance of a transport plan to obtain an initial approximate surface. Next, the mesh surface was optimized using operations including vertex relocation and edge collapses/flips to obtain feature-preserving results. Experiments demonstrate that our method can preserve sharp features while being robust to noise and missing data. [ABSTRACT FROM AUTHOR]

Compositional complex alloys, including high and medium‐entropy alloys (HEAs/MEAs) have displayed significant potential as efficient electrocatalysts for the oxygen evolution reaction (OER), but their structure‐activity relationship remains unclear. In particular, the basic question of which crystal facets are more active, especially considering the surface reconstructions, has yet to be answered. This study demonstrates that the lowest index {100} facets of FeCoNiCr MEAs exhibit the highest activity. The underlying mechanism associated with the {100} facet's low in‐plane density, making it easier to surface reconstruction and form amorphous structures containing the true active species is uncovered. These results are validated by experiments on single crystals and polycrystal MEAs, as well as DFT calculations. The discoveries contribute to a fundamental comprehension of MEAs in electrocatalysis and offer physics‐based strategies for developing electrocatalysts. [ABSTRACT FROM AUTHOR]

Background: Human amniotic membrane (AM) transplantation has been applied to treat ocular surface diseases, including corneal trauma. The focus of much deliberation is to balance the mechanical strength of the amniotic membrane, its resistance to biodegradation, and its therapeutic efficacy. It is commonly observed that the crosslinked human decellularized amniotic membranes lose the functional human amniotic epithelial cells (hAECs), which play a key role in curing the injured tissues. Methods and results: In this study, we crosslinked human decellularized amniotic membranes (dAM) with genipin and re-planted the hAECs onto the genipin crosslinked AM. The properties of the AM were evaluated based on optical clarity, biodegradation, cytotoxicity, and ultrastructure. The crosslinked AM maintained its transparency. The color of crosslinked AM deepened with increasing concentrations of genipin. And the extracts from low concentrations of genipin crosslinked AM had no toxic effect on human corneal epithelial cells (HCECs), while high concentrations of genipin exhibited cytotoxicity. The microscopic observation and H&E staining revealed that 2 mg/mL genipin-crosslinked dAM (2 mg/mL cl-dAM) was more favorable for the attachment, migration, and proliferation of hAECs. Moreover, the results of the CCK-8 assay and the transwell assay further indicated that the living hAECs' tissue-engineered amniotic membranes could facilitate the proliferation and migration of human corneal stromal cells (HCSCs) in vitro. Conclusions: In conclusion, the cl-dAM with living hAECs demonstrates superior biostability and holds significant promise as a material for ocular surface tissue repair in clinical applications. [ABSTRACT FROM AUTHOR]

Satellite multi-view stereo (MVS) is a fundamental task in large-scale Earth surface reconstruction. Recently, learning-based multi-view stereo methods have shown promising results in this field. However, these methods are mainly developed by transferring the general learning-based MVS framework to satellite imagery, which lacks consideration of the specific terrain features of the Earth's surface and results in inadequate accuracy. In addition, mainstream learning-based methods mainly use equal height interval partition, which insufficiently utilizes the height hypothesis surface, resulting in inaccurate height estimation. To address these challenges, we propose an end-to-end terrain feature-aware height estimation network named SA-SatMVS for large-scale Earth surface multi-view stereo, which integrates information across different scales. Firstly, we transform the Sobel operator into slope feature-aware kernels to extract terrain features, and a dual encoder–decoder architecture with residual blocks is applied to incorporate slope information and geometric structural characteristics to guide the reconstruction process. Secondly, we introduce a pixel-wise unequal interval partition method using a Laplacian distribution based on the probability volume obtained from other scales, resulting in more accurate height hypotheses for height estimation. Thirdly, we apply an adaptive spatial feature extraction network to search for the optimal fusion method for feature maps at different scales. Extensive experiments on the WHU-TLC dataset also demonstrate that our proposed model achieves the best MAE metric of 1.875 and an RMSE metric of 3.785, which constitutes a state-of-the-art performance. [ABSTRACT FROM AUTHOR]

The rapid technological development that geomatics has been experiencing in recent years is leading to increasing ease, productivity and reliability of three-dimensional surveys, with portable laser scanner systems based on Simultaneous Localization and Mapping (SLAM) technology, gradually replacing traditional techniques in certain applications. Although the performance of such systems in terms of point cloud accuracy and noise level has been deeply investigated in the literature, there are fewer works about the evaluation of their use for surface reconstruction, cartographic production, and as-built Building Information Model (BIM) creation. The objective of this study is to assess the suitability of SLAM devices for surface modeling in an urban/architectural environment. To this end, analyses are carried out on the datasets acquired by three commercial portable laser scanners in the context of a benchmark organized in 2023 by the Italian Society of Photogrammetry and Topography (SIFET). In addition to the conventional point cloud assessment, we propose a comparison between the reconstructed mesh and a ground-truth model, employing a model-to-model methodology. The outcomes are promising, with the average distance between models ranging from 0.2 to 1.4 cm. However, the surfaces modeled from the terrestrial laser scanning point cloud show a level of detail that is still unmatched by SLAM systems. [ABSTRACT FROM AUTHOR]

Seed geometric parameters are important in yielding trait scorers, quantitative trait loci, and species recognition and classification. A novel method for automatic measurement of three-dimensional seed phenotypes is proposed. First, a handheld three-dimensional (3D) laser scanner is employed to obtain the seed point cloud data in batches. Second, a novel point cloud-based phenotyping method is proposed to obtain a single-seed 3D model and extract 33 phenotypes. It is connected by an automatic pipeline, including single-seed segmentation, pose normalization, point cloud completion by an ellipse fitting method, Poisson surface reconstruction, and automatic trait estimation. Finally, two statistical models (one using 11 size-related phenotypes and the other using 22 shape-related phenotypes) based on the principal component analysis method are built. A total of 3400 samples of eight kinds of seeds with different geometrical shapes are tested. Experiments show: (1) a single-seed 3D model can be automatically obtained with 0.017 mm point cloud completion error; (2) 33 phenotypes can be automatically extracted with high correlation compared with manual measurements (correlation coefficient (R2) above 0.9981 for size-related phenotypes and R2 above 0.8421 for shape-related phenotypes); and (3) two statistical models are successfully built to achieve seed shape description and quantification. [ABSTRACT FROM AUTHOR]

Perovskite oxides have emerged as catalysts for electrochemical water splitting, and surface reconstruction is crucial for their electrocatalytic performance. In this study, we report the surface reconstruction of Ruddlesden–Popper-based oxides under nonreactive and electrochemical conditions. The rapid migration of Sr ions from the bulk to the surface results in a porous structure, increase the number of oxygen vacancies, and produces an A-site cation deficiency. Collectively, these modifications significantly enhance the electrocatalytic activity and stability for water oxidation. In addition, the engineered electrocatalysts have a low overpotential of 350 mV at 10 mA cm−2, alone with a Tafel slope of 77 mV dec−1. They also exhibit outstanding durability, maintaining a current density of 5 mA cm−2 over 6 h. [Display omitted] [ABSTRACT FROM AUTHOR]

To address the problem of incomplete perception of limited viewpoints of ore blocks in future remote and intelligent shoveling-dominated mining scenarios, a method of using new view generation technology to predict ore blocks with limited view based on a latent diffusion model is proposed. Initially, an ore block image-pose dataset is created. Then, based on prior knowledge, the latent diffusion model undergoes transfer learning to develop an intelligent ore block shape prediction model (IOBSPM) for rock blocks. During training, structural similarity loss is innovatively introduced to constrain the prediction results and solve the issue of discontinuity in generated images. Finally, neural surface reconstruction is performed using the generated multi-view images of rock blocks to obtain a 3D model. Experimental results show that the prediction model, trained on the rock block dataset, produces better morphological and detail generation compared to the original model, with single-view generation time within 5 s. The average PSNR, SSIM, and LPIPS values reach 23.02 dB, 0.754, and 0.268, respectively. The generated views also demonstrate good performance in 3D reconstruction, highlighting significant implications for future research on remote and autonomous shoveling. [ABSTRACT FROM AUTHOR]

A leading trend inmodern industry is hybridmanufacturing methods. The intention is to integrate additive and subtractive methods into a single machine. In such a process, it is difficult to evaluate the quality of the manufactured component between successive processes. A solution thatwouldmake it possible to determine the quality of a component produced by incremental technologies on the basis of forces recorded in amachining process is not yet available. In the present study, an attemptwasmade to reconstruct the surface of themachined workpiece solely on the basis of recorded forces during the groove micromilling process. A workpiece with a known surface geometry in the form of a sinuous wave was machined. The geometry of the workpiece corresponded to a structure typical of the selective laser sintering method for metallic powders. A process conducted with two different axial cutting depths was considered. The reconstructed surface profiles were evaluated by comparative analysis with the real machined surface. [ABSTRACT FROM AUTHOR]

This paper presents an approach to scattered data interpolation using q-Bézier triangular patches via an efficient algorithm. While existing studies have formed q-Bézier triangular patches through convex combination, their application to scattered data interpolation has not been previously explored. Therefore, this study aims to extend the use of q-Bézier triangular patches to scattered data interpolation by achieving C 1 continuity throughout the data points. We test the proposed scheme using both established data points and real-life engineering problems. We compared the performance of the proposed interpolation scheme with a well-known existing scheme by varying the q parameter. The comparison was based on visualization and error analysis. Numerical and graphical results were generated using MATLAB. The findings indicate that the proposed scheme outperforms the existing scheme, demonstrating a higher coefficient of determination ( R 2 ), smaller root mean square error (RMSE), and faster central processing unit (CPU) time. These results highlight the potential of the proposed q-Bézier triangular patches scheme for more accurate and reliable scattered data interpolation via the proposed algorithm. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiFe-W-O/NF pre-catalyst exhibits an ultrathin nanosheet structure (∼ 4.0 nm). • The active phase γ-NiOOH and FeOOH are efficiently activated by the high-valent W ions. • The synergistic effect of NiFeW tri-centers modulates the electronic structure and accelerates the reaction kinetics. • The assembled water splitting electrolyzer achieves current density of 10 mA cm−2 in alkaline at voltage of only 1.52 V. The efficient oxygen evolution reaction (OER) is crucial for various electrochemical processes, especially for overall water splitting (OWS). In this study, we focus on the utilization of WO 3-x as an activation medium to enhance the OER performance of NiFe-based electrocatalysts. Firstly, we synthesize WO 3-x nanowires supported on nickel foam (NF) and then incorporate NiFe on WO 3-x nanowires by a simple hydrothermal method. The WO 3-x self-supported NiFe (Oxy)hydroxide (denoted as NiFe-W-O/NF) shows a three-dimensional stereostructure composed of ultrathin nanosheets (∼ 4.0 nm). This unique structure provides a large open surface for fuller diffusion of the electrolyte while exposing more active sites. The electronic interaction of tri-centers of NiFeW accelerates the surface reconstruction process of γ-NiOOH and FeOOH, which are converted into the main active species in a short time. The electrochemical measurements confirm that the NiFe-W-O/NF has low OER overpotentials (233 mV at 10 mA cm−2, 298 mV at 100 mA cm−2) and excellent stability (100 h in total) in 1 M KOH electrolyte. In addition, the NiFe-W-O/NF || NiFe-W-O/NF battery also exhibits a low cell voltage (1.52 V at 10 mA cm−2) with a stable lifetime (50 h) under alkaline conditions. These results highlight the great potential of NiFe-W-O/NF for practical applications. [ABSTRACT FROM AUTHOR]

The steel–aluminum hybrid body closure panels can achieve a more balanced and lightweight performance. However, the differences in the physical properties of metal sheets and the complex changes in the properties of the adhesive material result in cumulative deviations in the composite-forming process. This paper proposes a deformation pre-compensation modeling method for the autobody closure panels hemming system oriented towards the process chain, in response to the problem that single-process optimization cannot obtain global optimal results. Taking the car door scaled model as an example, based on surface reconstruction and node compensation, the curing deformation amount is fed back in advance to the gluing and hemming processes. The deformation deviation is corrected through geometric parameter pre-compensation to achieve overall process shape control and optimization. Research shows that this method can significantly reduce the surface differences and gaps of hemming structures with dissimilar materials, and a single iteration can reduce the assembly surface difference by more than 90%. This provides a reference for improving the manufacturing quality of steel–aluminum hybrid body closure panels. [ABSTRACT FROM AUTHOR]

We present a reconstruction of the surface climate of the mid-Pliocene Warm Period (mPWP), specifically Marine Isotope Stage (MIS) KM5c or 3.205 Ma. We combine the ensemble of climate model simulations, which contributed to the Pliocene Model Intercomparison Project (PlioMIP), with compilations of proxy data analyses of sea surface temperature (SST). The different data sets we considered are all sparse with high uncertainty, and the best estimate of annual global mean surface air temperature (SAT) anomaly varies from 2.1 up to 4.8 °C depending on the data source. We argue that the latest PlioVAR analysis of alkenone data is likely more reliable than other data sets we consider, and using this data set yields an SAT anomaly of 3.9±1.1 °C, with a value of 2.8±0.9 °C for SST (all uncertainties are quoted at 1 standard deviation). However, depending on the application, it may be advisable to consider the broader range arising from the various data sets to account for structural uncertainty. The regional-scale information in the reconstruction may not be reliable as it is largely based on the patterns simulated by the models. [ABSTRACT FROM AUTHOR]

The schematic diagram illustrates that the N -doped carbon (NC) shells enhance the stability against carbonitride corrosion by suppressing surface reconstruction during the oxygen evolution reaction (OER). [Display omitted] • N -doped carbon encapsulated multimetallic carbonitrides were synthesized using urea-based gel. • The core-shell structure provided enhanced stability against oxidation during the OER. • Online mass spectrometric studies confirm improved carbon stability against oxidation. Electrocatalytic water splitting is a promising solution for generating clean hydrogen. Transition metal compounds are among the most extensively investigated catalysts developed to date for water oxidation in alkaline media, a process also known as the oxygen evolution reaction (OER). However, the application of these catalysts was constrained by insufficient stability arising from surface oxidation and metal dissolution under high OER potential. In this work, we developed a facile approach using urea-based gel as the precursor of preparing a series of multimetallic carbonitride particles which were encapsulated by N -doped carbon (NC). In particular, (MoCoFeNiZr)CN@NC core–shell structure delivered a low overpotential of 246 mV at a current density of 10 mA cm−2 in 1 M KOH during OER. Importantly, operando differential electrochemical mass spectrometry (DEMS), together with multiple microscopic and spectroscopic analyses, indicated that the NC shells effectively maintained the crystalline stability of carbonitride via suppressing the surface reconstruction during catalysis. The highly graphitic NC also demonstrates excellent stability against oxidation. This work shows a promising strategy of stabilizing electrocatalyst at high anodic potential, paving the way for the development of robust electrode materials for energy conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] Although zeolitic imidazolate frameworks (ZIFs) possess the merits of orderly porosity, high permeability, and easy functionalization, the transformation of ZIFs into the real active species and the promotion of the catalytic efficiency and stability are still challenging. Herein, CoMo-based three-dimensional (3D) hollow nanocages composed of interconnected nanosheets are fabricated by in-situ etching metal–organic framework (ZIF-67) under the aid of MoO 4 2−. X-ray photoelectron spectroscopy (XPS) and in-situ Raman confirm that Mo leaching can accelerate surface reconstruction and generate CoOOH active sites after continuous oxidation. Benefiting from the nanostructure and electronic properties after surface reconstruction, the engineered CoMo-30 exhibits the lowest overpotential of 280 mV at 30 mA cm−2 and robust stability over 110 h in 1 M KOH media for oxygen evolution reaction (OER), which significantly surpasses the other counterparts and commercial RuO 2. Density functional theory (DFT) calculations indicate that CoMo-30 has a lower free energy of *O → *OOH as rate determining step (RDS), suggesting that CoOOH sites play a crucial role in enhancing the activity and kinetics of OER. This work provides valuable insights into the rational design of hollow structures and the structure-composition-activity relationship during the electrochemical reaction process. [ABSTRACT FROM AUTHOR]

On-site electrochemical treatment of LaNiO 3 and intentional trace Fe3+ introduction simultaneously boost high OER activity and durability of perovskite oxides. [Display omitted] • The in situ electrochemical strategy is more viable for activity optimization. • The on-site electrochemical approach and intentional trace Fe3+ synergistically boost the activity and durability. • The electrochemically manipulated LaNiO 3 (i.e., deficient LaNiO 3−δ and NiO) is beneficial for surface reconstruction. Although decorated nanoparticles offer a great potential to generate extra active sites, their preparation usually requires time- and energy-consuming approaches. We report the remarkable activity and durability augmentation for the oxygen evolution reaction (OER) via effective and facile on-site electrochemical manipulation, using LaNiO 3 as a model catalyst. When compared to the pristine LaNiO 3 , the electrochemically manipulated LaNiO 3 cycled in Fe3+-containing 0.1 M KOH (i.e., E-LNO+Fe) exhibits an almost three-fold improvement in current density at 1.65 V. It is experimentally and theoretically shown that the electrochemical manipulation leads to the creation of defective LaNiO 3−δ and NiO on the surfaces, which accelerate phase transformation to (oxy)hydroxides and hence the OER. Furthermore, a Zn–air battery assembled with E-LNO+Fe has demonstrated superior activity by presenting 171 mW cm−2. Thus, our work demonstrates that substantial performance increases may be achieved by decorating and reconstructing perovskite-oxide electrodes via on-site electrochemical modification. [ABSTRACT FROM AUTHOR]

The Ce-CoSe 2 /MXene bifunctional electrocatalyst, featuring tip-shaped CoSe 2 nanoarrays and MXene heterogeneous interfaces, was successfully fabricated and exhibited outstanding performance for overall water splitting. DFT results indicate that the heterostructure enhances intermediate adsorption and facilitates HER/OER processes by reducing the kinetic barrier, thereby boosting electrocatalytic activity. [Display omitted] • Ce-CoSe 2 /MXene heterostructured catalysts were synthesized by simple hydrothermal and selenization reactions. • In situ Raman tests reveal the formation of CoOOH active phase is crucial for the electrocatalysis. • Ce-CoSe 2 /MXene electrocatalyst exhibits superior bifunctional electrocatalysis for water splitting.. Designing highly effective, low-cost bifunctional electrocatalysts without noble metals for overall water splitting remains a significant challenge. In this work, interfacial coupling of Ce-doped CoSe 2 nanoneedle arrays with MXene (Ce-CoSe 2 /MXene) is developed via the facile hydrothermal and selenization methods. The extensive specific surface area and favorable hydrophilicity of Ti 3 AlC 2 , combined with the optimized electronic structure and abundant active sites from Ce-doping and selenization, contribute to the exceptional bifunctional electrocatalytic performance of the Ce-CoSe 2 /MXene electrode. Specifically, this heterostructure achieves a low hydrogen evolution reaction (HER) overpotential of 34 mV at 10 mA cm−2, an oxygen evolution reaction (OER) overpotential of 279 mV at 100 mA cm−2, and an overall water splitting (OWS) potential as low as 1.45 V at 10 mA cm−2. In-situ Raman spectroscopy reveals that surface reconstruction would improve catalytic activity and stability. Theoretical calculations indicate that the Ce-CoSe 2 /MXene can improve the adsorption of intermediates and facilitate HER/OER process by lowering the kinetic barrier, thereby enhancing electrocatalytic activity. This research marks a substantial advancement in the development of low-cost, efficient electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimizing the crystalline structures and electronic properties of NiFe-MOFs by altering the organic ligands. • Ultra-low overpotentials and remarkable stability of NiFe-BDC in alkaline water/seawater. • Deciphering the surface reconstruction by various characterizations and in-situ measurements. • Unique NiFeOOH/NiFe-BDC heterojunction for low reaction barriers and fast reaction kinetics. Metal-organic frameworks (MOFs) have gained tremendous notice for the application in alkaline water/seawater oxidation due to their tunable structures and abundant accessible metal sites. However, exploring cost-effective oxygen evolution reaction (OER) electrocatalysts with high catalytic activity and excellent stability remains a great challenge. In this work, a promising strategy is proposed to regulate the crystalline structures and electronic properties of NiFe-metal-organic frameworks (NiFe-MOFs) by altering the organic ligands. As a representative sample, NiFe-BDC (BDC: C 8 H 6 O 4) synthesized on nickel foam (NF) shows extraordinary OER activity in alkaline condition, delivering ultralow overpotentials of 204, 234 and 273 mV at 10, 100, and 300 mA cm−2, respectively, with a small Tafel slope of 21.6 mV dec−1. Only a slight decrease is observed when operating in alkaline seawater. The potential attenuation is barely identified at 200 mA cm−2 over 200 h continuous test, indicating the remarkable stability and corrosion resistance. In-situ measurements indicate that initial Ni2+/Fe2+ goes through oxidation process into Ni3+/Fe3+ during OER, and eventually presents in the form of NiFeOOH/NiFe-BDC heterojunction. The unique self-reconstructed surface is responsible for the low reaction barrier and fast reaction kinetics. This work provides an effective strategy to develop efficient MOF-based electrocatalysts and an insightful view on the dynamic structural evolution during OER. [ABSTRACT FROM AUTHOR]

Through hydrothermal-induced interfacial reconstruction treatment, a multifaceted combination involving the spinel phase, oxygen vacancies, and reduced manganese is orchestrated to improve the anionic redox reversibility. The designed sample exhibits excellent rate capability and cycling stability, with ultra-low voltage decay of 0.91 mV cycle−1 after 150 cycles. [Display omitted] • Integrated introduction of spinel phase, oxygen vacancy, and reduced manganese in Li-rich layered oxides. • Enhanced initial couloumbic efficiency, superb rate capability, and advanced cycling stability with ultra-low voltage decay. • Chemical formulas unveil the underlying mechanism of surface defect engineering. • The modified sample has a 1.658% cell volume change, close to the "zero strain" of 1 %. • Density functional theory calculations provide comprehensive and in-depth insights. Cobalt (Co)-free lithium (Li)-rich layered oxides (LLOs) have emerged as promising cathode materials for the next generation of Li-ion batteries, attributed to their competitive market positioning and high energy density. Nevertheless, challenges arise from surface oxygen loss due to irreversible anionic redox reactions, leading to severe voltage and capacity decay that hinder the large-scale adoption of LLOs. Herein, we present an innovative, facile, and environmentally friendly hydrothermal approach to induce surface reconstruction of Li 1.2 Mn 0.6 Ni 0.2 O 2 material. A multifaceted combination involving the spinel phase, oxygen vacancies, and reduced manganese is orchestrated to alleviate the irreversible oxygen redox and impressively enhance Li-ion diffusion. The modified sample, owing to this surface transition, demonstrates low-strain and low-distortion properties along with a substantial improvement in structural stability, supported by both experimental validations and theoretical studies. As a result, the engineered sample exhibits exceptional capacity retention of 97.12% after 150 cycles at 1C, with an ultra-low voltage decay (0.91 mV cycle−1). Additionally, noteworthy enhancements in initial coulombic efficiency and rate performance are also observed. This straightforward surface defect engineering method offers a pathway to developing "low-strain" LLOs with superior electrochemical performance, thereby laying a solid foundation for future commercial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • SO 4 2−@Fe-NiOOH-O v /NiS was prepared by anodic oxidation and activation. • Doped Fe accelerates surface reconstruction and induces oxygen vacancies. • Doped Fe and oxygen vacancies reduce the surface adsorption energy of SO 4 2−. • The hydrogen bonding between SO 4 2− and *OOH promotes the formation of *OOH into O 2. There is an urgent need for highly active, durable, and low-cost electrocatalysts to overcome the shortcomings of high overpotential in the oxygen evolution reaction (OER) process. In this work, the nickel–iron hydroxysulfate rich in sulfate and oxygen vacancies (SO 4 2−@Fe-NiOOH-O v /NiS) is legitimately constructed. SO 4 2−@Fe-NiOOH-O v /NiS only requires a low overpotentials of 190 mV and 232 mV at 10 mA cm−2 and 100 mA cm−2 current densities in 1 M KOH, with excellent stability for 200 h at 100 mA cm−2 current density. In situ Raman spectroscopy and Fourier transform infrared spectroscopy demonstrated the stable adsorption of more SO 4 2− on the surface of catalyst. Density functional theory calculations testify surface reconstruction, doped Fe and oxygen vacancies significantly reduced the adsorption energy of sulfate on the surface. More importantly, the formation of *OOH to O 2 is facilitated by the highly hydrogen bonding between SO 4 2− and *OOH, accelerating the OER process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Iron-doped nickel cobalt phosphide nanoparticles are synthesized solvothermally. • In 1 M KOH, η 10 = 248 mV for electrocatalytic oxygen evolution. • The Fe 0.4 Co 0.8 Ni 0.8 P sustains the 100 h galvanostatic test. • Electron interaction boosts the oxygen evolution kinetics. Multi-metallic phosphides offer the possibility to combine the strategies of surface reconstruction, electronic interaction and mechanistic pathway tuning to achieve high electrocatalytic oxygen evolution activity. Here, iron-doped nickel cobalt phosphide nanoparticles (Fe x Co y Ni 2-x-y P) with the crystalline NiCoP phase are for the first time synthesized by the solvothermal phosphidization method via the reaction between metal–organic frameworks and white phosphorus. When used to electrochemically catalyze oxygen evolution reaction (OER), the Fe 0.4 Co 0.8 Ni 0.8 P supported by nickel foam requires only 248 mV overpotential to achieve 10 mA cm−2 current densities, and is robust towards the long-term OER in 1 M KOH. The higher number of electrochemically active sites can account for the good OER activity, along with the improved intrinsic activity which is caused by the electron interaction that optimizes the adsorption energy of hydroxyl intermediates, and that increases the acidity of high-valent metal centers. The OER mechanistic pathway involves both adsorbate and lattice oxygen. Surface conversion is observed after OER in alkaline solution, and metal phosphide layer transforms to metal oxides and (oxy)hydroxides. [ABSTRACT FROM AUTHOR]

A unique polyaniline (PANI) electron bridge was integrated into the metal–organic frameworks (MOFs)/layer double hydroxides (LDHs) heterojunction to expedite electron transfer from MOFs to LDHs, facilitating electron accumulation at the metal sites within MOF and electron-deficient LDHs and thus guiding the dynamic reconstruction. [Display omitted] • MIL-88B(Fe)@PANI@NiCo LDH heterojunctions with built-in electric field is built. • The built-in electric field induces an asymmetric interfacial electron distribution. • The PANI can serve as electron bridge to boost the electron transfer. • The dynamic reconstruction of MIL-88B(Fe)@PANI@NiCo LDH can be controlled. Tailoring the dynamic reconstruction of transition metal compounds into highly active oxyhydroxides through surface electron state modification is crucial for advancing water oxidation, yet remains a formidable challenge. In this study, a unique polyaniline (PANI) electron bridge was integrated into the metal–organic frameworks (MOFs)/layer double hydroxides (LDHs) heterojunction to expedite electron transfer from MOFs to LDHs, facilitating electron accumulation at the metal sites within MOF and electron-deficient LDHs. This configuration promotes the surface dynamic reconstruction of LDHs into highly active oxyhydroxides while safeguarding the MOF from corrosion in harsh environments over extended periods. The optimized electronic structure modification of both MOFs and LDHs enhances reaction kinetics. The superior MIL-88B(Fe)@PANI@NiCo LDH catalyst achieved 10 mA∙cm−2 at an overpotential of 202 mV and demonstrated stable operation for 120 h at this current density. This research introduces an innovative approach for guiding electron transfer and dynamic catalyst reconstruction by constructing a PANI electron bridge, potentially paving the way for more efficient catalytic systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mg-Ni/Fe 2 O 3 is successfully synthesized by a simple one-step corrosion method. • Mg doping promote the self-reconstruction of Mg-Ni/Fe 2 O 3 during OER. • Mg doping accelerates the oxygen intermediates evolution on Mg-Ni/Fe 2 O 3. • Mg-Ni/Fe 2 O 3 exhibits the excellent OER activity and stability in AEMWE. The acceleration of active sites formation through surface reconstruction is widely acknowledged as the crucial factor in developing high-performance oxygen evolution reaction (OER) catalysts for water splitting. Herein, a simple one-step corrosion method and magnesium (Mg)-promoted strategy are reported to develop the NiFe-based catalyst with enhanced OER performance. The Mg is introduced in NiFe materials to preparate a "pre-catalyst" Mg-Ni/Fe 2 O 3. In-situ Raman shows that Mg doping would accelerate the self-reconstruction of Ni/Fe 2 O 3 to form active NiOOH species during OER. In-situ infrared indicates that Mg doping benefits the formation of *OOH intermediate. Theoretical analysis further confirms that Mg doping can optimize the adsorption of oxygen intermediates, accelerating the OER kinetics. Accordingly, the Mg-Ni/Fe 2 O 3 catalyst exhibits excellent OER performance with overpotential of 168 mV at 10 mA cm−2. The anion exchange membrane water electrolyzer achieved 200 mA cm−2 at voltage of 1.53 V, showing excellent stability over 500 h as well. This work demonstrates the potential of Mg-promoted strategy in regulating the activity of transition metal-based OER electrocatalysts. [ABSTRACT FROM AUTHOR]

P-MoO 2 @CoNiP exhibits excellent HER and UOR catalytic activities. The HER performance of the catalyst can be enhanced by the leaching and reabsorption of Mo, while the UOR performance of the catalyst is improved by the reconstruction to form NiOOH. [Display omitted] • P-MoO 2 @CoNiP has a hierarchical structure of nanosheets covering the nanorods. • The abundance of active sites on P-MoO 2 @CoNiP enhances its catalytic activity. • The leaching/reabsorption of Mo improves the HER activity of P-MoO 2 @CoNiP. • Co and P incorporation boosts NiOOH formation, enhancing the activity of UOR. • P-MoO 2 @CoNiP shows efficient bifunctional catalytic activity for HER and UOR. Combining the urea oxidation reaction (UOR) with the hydrogen evolution reaction (HER) is an effective technology for energy-saving hydrogen production. Herein, a bifunctional electrocatalyst with CoNiP nanosheet coating on P-doped MoO 2 nanorods (P-MoO 2 @CoNiP) is obtained via a two-step hydrothermal followed a phosphorization process. The catalyst demonstrates exceptional alkaline HER performance due to the formation of MoO 2 and the dissolution/absorption of Mo. Meanwhile, the inclusion of Co and P in the P-MoO 2 @CoNiP catalyst facilitated the formation of NiOOH, enhancing UOR performance. Density functional theory calculations reveal that the hydrogen adsorption Gibbs free energy (ΔG H*) of P-MoO 2 @CoNiP is closer to 0 eV than CoNiP, favoring the HER. The catalyst only needs −0.08 and 1.38 V to reach 100 mA cm−2 for catalyzing the HER and UOR, respectively. The full urea electrolysis system driven by P-MoO 2 @CoNiP requires 1.51 V to achieve 100 mA cm−2, 120 mV lower than the traditional water electrolysis. [ABSTRACT FROM AUTHOR]

The electronic structures of Fe and Ni in FNS were fine-tuned by P doping, resulting in suppressed Fe leaching, improved electrical conductivity of FNS, and facilitated formation of NiOOH on catalyst surface. In turn, these features enhanced the OER activity and stability. [Display omitted] The pentlandite Fe 5 Ni 4 S 8 (abbreviated as FNS) is not efficient for water splitting because of its inferior performance for the oxygen evolution reaction (OER). This issue originates from the low activity and instability of FNS during the OER process but can be solved through appropriate doping. Herein, a P-doping strategy based on annealing in the presence of NaH 2 PO 2 as a phosphorus source upstream was employed on FNS to enhance its activity and stability toward OER. The results demonstrated fine-tuned electronic structures of Fe and Ni in FNS through P-doping, resulting in suppressed Fe leaching, improved electrical conductivity of FNS, and easier formation of NiOOH on the surface of the catalyst. In turn, these features enhanced the OER activity and stability. The optimal P-doped FNS catalyst FNSP-40 exhibited a 4-fold greater electrochemical surface area compared to that of FNS, accompanied by an overpotential of 235 mV at 10 mA cm−2. The optimized FNSP-40 catalyst was used as an anode, and platinum-decorated FNS was used as a cathode. This combination demonstrated an electrolysis performance with a cell voltage of 1.57 V, reaching a current density of 100 mA cm−2, which indicates efficient operation. The advantages of P-doping engineering were also verified in simulated seawater with enhanced OER performance. Overall, the proposed strategy looks promising for the fabrication of pentlandite-structured catalysts for efficient alkaline water and seawater oxidation. [ABSTRACT FROM AUTHOR]

[Display omitted] The design strategy of designing effective local electronic structures of active sites to improve the oxygen evolution reaction (OER) performance is the key to the success of sustainable alkaline water electrolysis processes. Herein, a series of manganese-doped nickel molybdate porous nanosheets with rich oxygen vacancies on the nickel foam (Mn-NiMoO 4 /NF PNSs) synthesized by the facile hydrothermal and following annealing routes are used as high-efficiency and robust catalysts towards OER. By virtue of unique nanosheets architectures, more exposed active site, rich oxygen vacancies, tailored electronic structures, and improved electrical conductivity induced by Mn incorporation, as predicted, the optimized Mn 0.10 -NiMoO 4 /NF PNSs catalyst exhibits superior the OER performance with a low overpotential of 211 mV at 10 mA‧cm−2, a small Tafel slope of 41.7 mV‧dec-1, and an excellent stability for 100 h operated at 100 mA‧cm−2 in 1.0 M KOH electrolyte. The in-situ Raman measurements reveal the surface dynamic reconstruction. Besides, the results of density functional theory (DFT) calculations unveil the reaction mechanism. This study provides an effective design strategy via Mn incorporation to synergistically engineer electronic structures and oxygen vacancies of metal oxides for efficiently boosting the OER performance. [ABSTRACT FROM AUTHOR]

High-resolution digital elevation models (DEMs) of the lunar surface are crucial for lunar exploration missions and scientific research. The emergence of advanced technologies, such as Shape-from-Shading (SfS), has enabled the generation of pixel-wise high-resolution DEMs from monocular images of the lunar surface. However, SfS encounters significant challenges in locations with limited illumination, such as the lunar south pole, where the surface is largely covered by shadows. Therefore, this paper presents a novel shadow-constrained SfS approach for pixel-wise 3D surface reconstruction at the lunar south pole. The proposed approach uses multiple high-resolution images captured under different illumination conditions and an existing low-resolution DEM as the inputs and generates a high-resolution DEM with the same resolution as that of the input image through hierarchical SfS processing incorporating shadow constraints. Experiments were conducted using actual images collected by the Lunar Reconnaissance Orbiter (LRO) Narrow Angle Camera (NAC) at the lunar south pole. Comparisons with respect to photogrammetric DEMs generated from stereo NAC images show that the DEMs generated using the proposed approach exhibit the smallest root mean square error (RMSE). Moreover, shaded relief images rendered from the DEMs generated using the proposed approach demonstrate the highest similarity to the actual NAC images. Detailed profile comparisons further validate the effectiveness of the shadow constraint in optimizing 3D reconstruction in regions in proximity to shadows and within shadowed regions. The proposed shadow-constrained SfS approach can be used to generate high-resolution DEMs to support future missions to explore the lunar south pole, with applications including landing site evaluation and route planning for lunar probes or astronauts.

In the field of electrocatalysis, most of the electrodes have the problem of poor mechanical properties, which leads to the electrode can not be used on a large scale. At present, most bulk electrodes are used to study their mechanical properties due to their unique phase composition distribution and facile fabricate methods. But their novel properties in the field of electrocatalysts have not been fully developed. Multi-element bulk electrodes not only diversified the electronic states, but also build complex surface morphology by different dissolution rate between multi-phase distribution. In this paper, we synthesized the FeNiMo bulk electrode for oxygen evolution reaction (OER) with two-phase coexistence of Mo-doped face center cubic phase (FCC) and Mo-rich intermetallic compound (IMC) phase. During cyclic voltammetry activation, the surface reconstruction of Mo-rich IMC phases generated by ion leaching leaves Fe–Ni pore structures with more active area, which enhances OER performance. Meanwhile, the electron states get more diverse on the surface of remaining FCC phases due to Mo doping, which provides more suitable sites for four-step OER process. The FeNiMo electrode shows an ultra-low overpotential of 212 mV and 293.4 mV at a current density of 10 mA cm−2 and 100 mA cm−2, respectively. Moreover, it can maintain stability at 100 mA cm−2 for up to 72 h. This work provides a strategy for studying the relationship between phase composition and electrochemical performance of alloy bulk electrodes.