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Unstable Zn metal anodes with dendrites/side reactions are becoming the main obstacle to the practical application of zinc‐based aqueous batteries. Epitaxial growth has been considered to be an effective strategy for solving these issues, especially for inducing the (002) plane growth. Nonetheless, the (002)‐textured Zn is difficult to achieve highly stable Zn anode under high capacity resulting from its large lattice distortion. Herein, the Cu single atom anchored polymeric carbon nitride (Cu@PCN) is synthesized by a facile thermal polymerization method. Serving as multifunctional protective layer on Zn surface, the Cu@PCN can provide massive nucleation sites at a nano‐level and uniformize the electron distribution through coordination engineering. Optimizing the coordination structures of single Cu and N atoms within the carbon matrix enables a redistribution for electric field and regulates ion flux. More importantly, this coordination strategy with single atoms is first reported to customize oriented and continuous phase epitaxy along highly dendrite‐resistant Zn(101) plane by reducing (101) surface energy. This pattern of oriented dense deposition leads to stable and reversible Zn plating/stripping is achieved, which delivers an extended cycling life of 550 h at 10 A cm−2, 20 mAh cm−2. The practical full cell also displays stable performance for 1200 cycles. [ABSTRACT FROM AUTHOR]

In this study, a titanium alloy substrate was cladded with TC17 titanium alloy powder using the pulsed-current (PC)-assisted laser cladding technique. The primary objective of this research was to assess the impact of varying pulsed current intensities on the morphology, microstructure, and properties of samples. It is observed that the utilization of pulsed currents significantly enhances the metallurgical adhesion between the samples, concurrently diminishing the occurrence of porosity within the cladding layer. The incorporation of a pulsed current also has a positive impact on the microhardness and corrosion resistance of the samples. Furthermore, the synergistic influence of laser energy and a pulsed electrical current is found to promote a structural evolution in materials towards a state with lower electrical resistance. The introduction of a pulsed current leads to preferential growth of β grains with <100>// cladding direction in the cladding zone and obtains the typical {100} < 001 > cube texture, while the substrate zone exhibits a distinctive stripe-like configuration formed by the primary α-phase constituents. The outcomes of this study show the pivotal role of pulsed currents as an auxiliary technique for enhancing the properties and effecting microstructural modifications in titanium alloys during the laser cladding process. [ABSTRACT FROM AUTHOR]

Tailoring recrystallization via particle-stimulated nucleation (PSN) and pinning effects from secondary phase particles effectively weakens textures, which is still challenging for low-alloyed rare earth-free Mg alloys. Herein, the texture of a dilute cold-rolled Mg-2.2Al-0.33Ca (wt.%) alloy is found to reduce with the appearance of transverse direction (TD) texture components during static recrystallization. The texture transition is mainly attributed to the preferential growth of TD-oriented recrystallized grains, resulting from the preferential segregation of Al and Ca atoms on basal-oriented grain boundaries with low misorientation angles. The findings provide an in-depth understanding of texture modification in Mg alloys.

Rolling texture impacts the formability and usability of steel due to the anisotropy, but it is difficult to remove even after annealing. This work found that the electropulsing treatment can eliminate the hot-rolled and annealed texture in 35CrMo steel (//ND, normal direction, and //RD, rolling direction) at a relatively lower current density and produce a new texture along the current direction via higher current density. Furthermore, the electropulse-induced texture evolution law was established by preparing gradient current density in steel. Electron backscattered diffraction and micro-region X-ray diffraction were used to study texture evolution. By analyzing the texture evolution at different stages of the phase transition, it is concluded that the electropulse-induced texture change mainly occurs at the grain growth stage. The suppression and preferential grain growth caused by different scattering degrees of electron flow with various grain orientations are thought to be responsible for the observed phenomenon.

Tailoring recrystallization via particle-stimulated nucleation (PSN) and pinning effects from secondary phase particles effectively weakens textures, which is still challenging for low-alloyed rare earth-free Mg alloys. Herein, the texture of a dilute cold-rolled Mg-2.2Al-0.33Ca (wt.%) alloy is found to reduce with the appearance of transverse direction (TD) texture components during static recrystallization. The texture transition is mainly attributed to the preferential growth of TD-oriented recrystallized grains, resulting from the preferential segregation of Al and Ca atoms on basal-oriented grain boundaries with low misorientation angles. The findings provide an in-depth understanding of texture modification in Mg alloys. The anisotropic co-segregation of Al and Ca on grain boundaries is responsible for the texture weakening of a dilute Mg-Al-Ca alloy, which provides a strategy for texture modification in such alloys. [ABSTRACT FROM AUTHOR]

In this work, Ti3Al1−xSixC2 (x=0, 0.2, 0.4, and 0.6) with Al/Si solid solution structure are synthesized, and the effects of Si on their oxidation behaviors at 1000 °C are evaluated. The addition of Si not only contributes to the formation of Ti5Si3 impurity but also affects the composition of the oxide scale. Particularly, the incorporation of Si in the TiO2 lattice is demonstrated, which alters the formation energy of the (110) plane in TiO2, thus leading to the preferential growth of Si‐doped TiO2 to dendritic congeries. Moreover, the Si addition is believed to affect mass transportation during the oxidation process, which accelerates the formation of a continuous Al2O3 layer in the oxide scale. With an optimized Si content, the oxidation of Ti3Al1−xSixC2 is restrained. However, with excess Si content, the continuity of the resulting Al2O3 layer is destroyed, thus the oxidation rate rises again. [ABSTRACT FROM AUTHOR]

The grain growth process plays an important role in the texture formation in magnesium alloys. The microstructural and micro-textural evolution of a cold-rolled Mg–Zn–Gd alloy during annealing at 350 °C for 60–190 min were tracked by quasi-in-situ electron backscatter diffraction method. The results show that grain growth takes place gradually with the annealing time increasing. Moreover, the TD-split texture maintains the texture type but alters in three aspects - the increased tilting angle, the decreased pole intensity and the widened distribution of high-intensity area. Grains with their c-axis tilting 45–70° from normal direction show preferential growth which is closely associated with the texture changes. The original grain size advantage is one of the important factors leading to the growth advantage, some grain boundaries, such as 50–60° [1¯21¯0], 50–60° [2¯75¯0], 60–70° [1¯21¯0] (∑18b), and 70–80° [101¯0] (∑10) are also considered to be related to this preferential growth.

Herein, the interfacial compound growth kinetics and corresponding mechanisms in Sn-0.7Cu/Cu solder joint at aging stage were investigated using both experiments and molecular dynamics simulations. The research results indicate that, the growth rates of interfacial IMCs (Cu 6 Sn 5 IMC and Cu 3 Sn IMC) are affected by the aging temperature severely, the higher aging temperature leads to the larger growth kinetics for both Cu 6 Sn 5 IMC and Cu 3 Sn IMC. At aging stage, Cu substrate continuously supplies Cu 3 Sn IMC with Cu atoms. Those Cu atoms diffuse across Cu 3 Sn IMC to the Cu 3 Sn/Cu 6 Sn 5 interface and react with Sn atoms diffused from the Sn-based solder to form new Cu 3 Sn grains growing towards Cu 6 Sn 5 IMC, and the main crystal orientations are (100), (42–1), and (3−10). As the grain boundary diffusion rate of Cu atoms in Cu 3 Sn IMC determines the Cu Sn reaction rate (new Cu 3 Sn grains formation rate) on Cu 3 Sn/Cu 6 Sn 5 interface, the growth of Cu 3 Sn IMC is driven by grain boundary diffusion, which is manifested by a growth index n near to 0.3. Meanwhile, the rod-like Cu 6 Sn 5 IMC preferentially grows into Sn-based solder attributed to the large number of Cu atoms provided by Cu 3 Sn IMC, which can diffuse to the top of Cu 6 Sn 5 IMC and reacts with Sn-based solder. While when Cu 6 Sn 5 IMC is thick enough, Cu atoms cannot reach to the top of Cu 6 Sn 5 IMC anymore, but diffuse laterally within the Cu 6 Sn 5 grains, resulting in the widening of scallop-like Cu 6 Sn 5 IMCs. As the thickening of Cu 6 Sn 5 IMC is caused by the growth of the existing Cu 6 Sn 5 grains, the diffusion of Cu and Sn atoms in Cu 6 Sn 5 grains plays a decisive role. Therefore, the growth of Cu 6 Sn 5 IMC is driven by bulk diffusion, which is manifested by a growth index n near to 0.5. [Display omitted] • Cu substrate supplies element Cu to joint, resulting in the thickening of interfacial IMCs. • Cu 6 Sn 5 grows into Sn-based solder and Cu 3 Sn grows towards Cu 6 Sn 5 side. • The thickening of Cu 6 Sn 5 IMC is caused by the growth of the existing Cu 6 Sn 5 grains. • The thickening of Cu 3 Sn IMC is attributed to the generation of new Cu 3 Sn grains. • Growths of Cu 6 Sn 5 and Cu 3 Sn are driven by bulk and boundary diffusions, respectively. [ABSTRACT FROM AUTHOR]

Organic-inorganic halide perovskites (OIHP) are an emerging family of semiconductor materials widely used in the fabrication of optoelectric devices, including solar cells, due to their superior optical and electrical properties. Poor long-term stability of OIHPs is the main hindrance to the commercialization of perovskite solar cells. Using 2D Ruddelsden-Popper perovskites is a common approach to improve perovskite solar cell stability. However, their 2D structure restricts the transport of charges, thus reduces the photovoltaic performance of perovskite solar cells. Out-of-plane growth of 2D perovskite film can significantly improve carrier transport and consequently reduces the rate of non-radiative recombination. One of the main factors that affects the preferential growth of 2D perovskites is the type of spacer cation that exists in the 2D perovskites structure. Herein, butylammonium (BA+) and phenetylammonium (PEA+) spacer cations, as well as their combination, are employed in 2D perovskite thin film, and their effects on preferential growth and phase segregation have been investigated. X-ray diffraction (XRD) data shows that the BA-based 2D perovskite has a more desirable (220) preferential direction, but the preferred peaks of PEA-based 2D perovskite have higher intensity and narrower full width at half maximum (FWHM) than the BA-based counterparts, which is due to the rigid nature of the PEA+ compared to the BA+ molecule. It is also observed that the replacement of BA+ instead of PEA+ significantly reduces phase segregation. This phenomenon is probably related to the phenyl ring of the PEA+ molecule, which is entirely solvophobic and slows down the formation of DMF.PEAI complex during the crystallization step, which in turn leads to the formation of small n 2D perovskite nucleus causing phase segregation. SEM images also represent that the BA, PEA-based film has a smoother surface and lower pinholes than the PEA and BA-based 2D perovskite. [ABSTRACT FROM AUTHOR]

The grain growth process plays an important role in the texture formation in magnesium alloys. The microstructural and micro-textural evolution of a cold-rolled Mg–Zn–Gd alloy during annealing at 350 °C for 60–190 min were tracked by quasi-in-situ electron backscatter diffraction method. The results show that grain growth takes place gradually with the annealing time increasing. Moreover, the TD-split texture maintains the texture type but alters in three aspects - the increased tilting angle, the decreased pole intensity and the widened distribution of high-intensity area. Grains with their c-axis tilting 45–70° from normal direction show preferential growth which is closely associated with the texture changes. The original grain size advantage is one of the important factors leading to the growth advantage, some grain boundaries, such as 50–60° [ 1 ¯ 2 1 ¯ 0 ], 50–60° [ 2 ¯ 7 5 ¯ 0 ], 60–70° [ 1 ¯ 2 1 ¯ 0 ] (∑18b), and 70–80° [ 10 1 ¯ 0 ] (∑10) are also considered to be related to this preferential growth. [ABSTRACT FROM AUTHOR]

Constructing hydroxide precursors with radially oriented primary grains is the key factor for fabricating Ni-rich cathodes with sufficient cycle life. Herein, hydroxide precursors with composition of Ni 0.92 Co 0.04 Mn 0.04 (OH) 2 were synthesized to study the effects of pH and ammonia concentration on the phase, morphology, and orientation of grains, as well as the evolution of primary grains and secondary particles during industrial-scale continuous precipitation process. Results show that the preferential growth of primary grains varies significantly with change of pH, ammonia concentration and the growth of secondary particles. Meanwhile, the variation of grain size along direction parallel to [001] is more obvious than that perpendicular to [001] after decreasing pH or increasing ammonia concentration. Moreover, the size distribution of secondary particle varies with the increase of feeding time or the change of reaction condition in a regular manner. Although a steady state could be reached for continuous precipitation, the different residence times endow the size of secondary particles with normal distribution. The results disclosed in this work may provide a guiding significance for designing precipitation procedure for hydroxide precursor of high-end Ni-rich cathodes. [Display omitted] • Synthesis of Ni 0.92 Co 0.04 Mn 0.04 (OH) 2 via industrial-scale continuous precipitation. • Effects of pH and ammonia concentration on orientation of grains. • Evolution of grain orientation during growth of secondary particle. • Variation of secondary particle with change of condition and feeding time. [ABSTRACT FROM AUTHOR]

By Plasma Spray-Physical Vapor Deposition (PS-PVD), major fractions of the powder feedstock can be evaporated so that the coating builds up mainly from vapor phase. In this work, the deposition mechanisms at different PS-PVD conditions were investigated. Depending on the plasma flow conditions and the substrate temperature, the columns in the coatings possess successively pyramidal, cauliflower, and lamellar shaped tops. In addition, the different microstructures show characteristic crystallographic textures, in which different in-plane and out-of-plane orientations were observed by pole figures. Based on investigations by electron back-scatter diffraction (EBSD), the overall coating growth process can be roughly divided into three subsequent stages: equiaxed growth, competitive growth, and preferential growth. Influences of diffusion and shadowing on final coating microstructure and orientation were discussed. The formation of equiaxed grains was proposed to be caused by high nucleation rates, which are probably induced by large undercooling and super-saturation at the beginning of deposition. The preferential growth orientation was preliminarily explained based on an evolutionary selection mechanism. [ABSTRACT FROM AUTHOR]

In this study, a titanium alloy substrate was cladded with TC17 titanium alloy powder using the pulsed-current (PC)-assisted laser cladding technique. The primary objective of this research was to assess the impact of varying pulsed current intensities on the morphology, microstructure, and properties of samples. It is observed that the utilization of pulsed currents significantly enhances the metallurgical adhesion between the samples, concurrently diminishing the occurrence of porosity within the cladding layer. The incorporation of a pulsed current also has a positive impact on the microhardness and corrosion resistance of the samples. Furthermore, the synergistic influence of laser energy and a pulsed electrical current is found to promote a structural evolution in materials towards a state with lower electrical resistance. The introduction of a pulsed current leads to preferential growth of β grains with <100>// cladding direction in the cladding zone and obtains the typical {100} < 001 > cube texture, while the substrate zone exhibits a distinctive stripe-like configuration formed by the primary α-phase constituents. The outcomes of this study show the pivotal role of pulsed currents as an auxiliary technique for enhancing the properties and effecting microstructural modifications in titanium alloys during the laser cladding process.

A series of ZriS thin films with a thickness of 400 nm were grown on Si substrate by pulsed laser deposition, and an in-situ annealing treatment was performed to obtain a single-crystal zinc blende ZnS thin film. Tt was reported for the first time that the single-crystal ZriS film with a cubic structure of sphalerite was obtained after in-situ annealing treatment, and the film was preferentially grown along the (111) crystal plane. The relationship between the crystal quality and the annealing process was also studied. The results show that as the annealing temperature increased ？ the average grain size of the film increased from 13,357 nm at 200 °C to 27.232 nm at 400 °C, while the average roughness of the film decreased from 2.05 to 1 J 4 nm. The ZnS film prepared by pulsed laser deposition showed excellent single crystal orientation growth and good surface flatness after annealing at 400 °C, which provided an experimental solution for the study of single-crystal ZnS film. [ABSTRACT FROM AUTHOR]

In the present study, the effect of titania (TiO2) substrate grain size and orientation on the epitaxial growth of TiO2 splat was investigated. Interestingly, the splat presented comparable grain size with that of substrate, indicating the hereditary feature of grain size. In addition, hetero- and homo-orientation epitaxial growth was observed at deposition temperatures below 400 °C and above 500 °C, respectively. The preferential growth of high-energy (001) face was also observed at low deposition temperatures (≤ 400 °C), which was found to result from dynamic nonequilibrium effect during the thermal spray deposition. Moreover, thermal spray deposition paves the way for a new approach to prepare high-energy (001) facets of TiO2 crystals. [ABSTRACT FROM AUTHOR]

In this work, we report on the anisotropic growth of α -Fe 2 O 3 nanoslabs which are produced by co-precipitation method with the addition of sucrose. In our previous work, we have argued that such behavior can be related with the chelating agent. Experiments of X-ray diffraction (XRD), high-resolution transmission electronic microscopy (HRTEM) and magnetic measurements as a function of temperature and an applied magnetic field are used to characterize the samples. The HRTEM image of the sample prepared with 10 mmol/l of sucrose consists of faceted-like nanoslabs while that prepared without sucrose exhibits particles with a non-uniform shape. In this way, we can state that both the HRTEM images and the analysis of the XRD patterns show clearly a preferential growth of the [110] crystallographic direction. To strengthen our supposition, besides T - and field-dependence of magnetization are consistent with a superparamagnetic behavior the fit of the (Zero Field Cooling and Field Cooling) ZFC-FC curve for sample grown with 10 mmol/l of sucrose presents a strong increase of the effective anisotropy constant, K eff , which can be related with the increasing of the shape magnetic anisotropy. [ABSTRACT FROM AUTHOR]

We reverse engineer entropy formulas from entropic divergence, optimized to given classes of probability distribution function (PDF) evolution dynamical equation. For linear dynamics of the distribution function, the traditional Kullback−Leibler formula follows from using the logarithm function in the Csiszár’s f-divergence construction, while for nonlinear master equations more general formulas emerge. As applications, we review a local growth and global reset (LGGR) model for citation distributions, income distribution models and hadron number fluctuations in high energy collisions.

By using the Amsterdam density functional (ADF) program based on first-principles, we have in detail investigated the Zn ( n = 2-20) clusters, several series of stacked structures, and the growth mechanism of zinc nanorods on silicone oil surfaces, which are isotropic, and can be generally considered as quasi-free sustained substrates. For the Zn ( n = 2-20) clusters, some new ground-state structures are found. The additional boundary atoms can enhance the stability of the stacked structures containing unit cells. The structures from the transverse array of the unit cells on (002) crystal plane are more stable than those stacked along the [002] direction as atomic number increases. The transverse arrayed structures can grow along the [002] direction. However, there is an atomic dislocation between the (002) crystal planes. In fact, the dislocation forms its one side surface of (101). By means of a single point SCF calculation in the ADF program, the adsorption energies per atom on the (101) and (002) crystal planes are calculated. According to the Boltzmann distribution probability law, the adsorption probability on the (101) plane is larger than that on the (002) plane, and the ratio between them is about 24-900. This shows that the Zn nanorods grow preferentially along the [110] direction on the (101) planes. These are in good agreement with our experimental findings. [ABSTRACT FROM AUTHOR]

In the present study, uniform foursquare BiOCl nanosheets with highly exposed {001} facets were facilely synthesized via a simple, fast and mild hydrothermal route using cationic polyacrylamide (C-PAM) as both chlorine source and surfactant. The as-prepared BiOCl samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) to investigate their crystalline phases, morphologies and composition. N 2 adsorption/desorption measurement was conducted to determine the surface area and pore volume of the samples while zeta potential was measured to investigate their surface properties. It was revealed that the experimental parameters such as reaction temperature, time and the amount of additives (e.g., sodium hydroxide, C-PAM and sodium citrate) played vital roles in the formation of BiOCl nanosheets. The band gap of the typical-synthesized BiOCl nanosheets was estimated to be 3.33 eV from the UV–Vis diffuse reflectance spectrum (DRS). The photoluminescence (PL) emission spectrum of the BiOCl nanosheets could be fitted to Gaussian distribution with three emission bands centered at 404.9, 447.6 and 530.6 nm, respectively. Photocatalytic experiments were carried out by degrading the organic dyemethyl orange (MO), indicating the high catalytic activity of the BiOCl samples. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we have demonstrated that europium oxide (Eu2O3) is a new type of active catalyst for single-walled carbon nanotubes (SWNTs) growth under suitable conditions. Both random SWNT networks and horizontally aligned SWNT arrays are efficiently grown on silicon wafers. The density of the SWNT arrays can be altered by the CVD conditions. This result further provides the experimental evidence that the efficient catalyst for SWNT growth is more size dependent than the catalysts themselves. Furthermore, the SWNTs from europium sesquioxides have compatibly higher quality than that from Fe/Mo catalyst. More importantly, over 80% of the nanotubes from Eu2O3 are semiconducting SWNTs (s-SWNTs), indicating the preferential growth of s-SWNTs from Eu2O3. This new finding could open a way for selective growth of s-SWNTs, which can be used as high-current nanoFETs and sensors. Moreover, the successful growth of SWNTs by Eu2O3 catalyst provides new experimental information for understanding the preferential growth of s-SWNTs from Eu2O3, which may be helpful for their controllable synthesis.

Rhombohedron-like LiFePO 4 platelets with preferentially exposed (010) plane are synthesized via solvothermal reaction using 30 vol.% Polyethylene glycol (PEG) solution as solvent. The mechanism of the PEG-induced crystal growth of the LiFePO 4 platelets under solvothermal circumstance is revealed. The crystal structure, micro morphology and electrochemical performance of the prepared LiFePO 4 platelets are studied by means of X-Ray diffraction (XRD), scanning electron microscope (SEM), high-resolution transmission electron microscopy (HRTEM), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge test. Due to the preferential growth of (010) lattice plane facilitating diffusion of Li-ions, the LiFePO 4 material shows excellent electrochemical performance. The as-obtained products deliver initial discharge capacities of 166.8 mAh g − 1 with an initial Coulombic efficiency of 99.4% at 0.1C, discharge capacities of 144.7 mAh g − 1 at 1C and discharge capacities of 116.5 mAh g − 1 at 5C. Moreover, the discharge capacities after 262 cycles at 1C are 142.4 mAh g − 1 (capacity retention is 98.4%). This solvothermal reaction approach is a promising strategy for the commercialization of LiFePO 4 cathode in lithium ion batteries. [ABSTRACT FROM AUTHOR]

A novel <0001>//ED (<0001>) texture was obtained in Mg-9Gd-5Y-0.5Zr alloy by hot extrusion at 350 °C. The formation mechanism of <0001> texture during extrusion was studied by independent analysis of plastic deformation mechanism, recrystallized (DRXed) behavior, and grain growth. The results showed that the plastic deformation mechanism was dominated by the traditional basal slip, resulting in a strong <10-10>//ED (<10-10>) basal texture at the initial stage of extrusion. The <10-10> texture was gradually weakened by the random nucleation of DRXed behavior dominated by discontinuous dynamic recrystallization (DDRX) and supplemented by continuous dynamic recrystallization (CDRX). Finally, the <0001> texture was formed due to the preferential growth of the low-energy <0001>//ED grains during grain growth process. Compared with the formation of conventional <10-10> texture by hot extrusion in the Mg–Gd series alloys, the formation of the <0001> texture in the as-extruded Mg-9Gd-5Y-0.5Zr alloy achieved outstanding room temperature ductility and hardening ability. The elongation (EL) and uniform elongation (UEL) reached 31.5% and 20.2%, respectively. • A novel <0001> texture (<0001>//ED) was obtained in Mg-9Gd-5Y-0.5Zr alloy by hot extrusion at 350 °C. • Microstructure and texture evolution during hot extrusion were demonstrated. • The formation mechanism of <0001> texture during extrusion was studied. • The strength and ductility of Mg–Gd series alloys with <10-10> and <0001> textures were compared. [ABSTRACT FROM AUTHOR]

In this work, Ti 3 Al 1-x Si x C 2 (x=0, 0.2, 0.4, and 0.6) with Al/Si solid solution structure are synthesized, and the effects of Si on their oxidation behaviors at 1000 °C are evaluated. The addition of Si not only contributes to the formation of Ti 5 Si 3 impurity but also affects the composition of the oxide scale. Particularly, the incorporation of Si in the TiO 2 lattice is demonstrated, which alters the formation energy of the (110) plane in TiO 2 , thus leading to the preferential growth of Si-doped TiO 2 to dendritic congeries. Moreover, the Si addition is believed to affect mass transportation during the oxidation process, which accelerates the formation of a continuous Al 2 O 3 layer in the oxide scale. With an optimized Si content, the oxidation of Ti 3 Al 1-x Si x C 2 is restrained. However, with excess Si content, the continuity of the resulting Al 2 O 3 layer is destroyed, thus the oxidation rate rises again., (© 2022 Wiley-VCH GmbH.)

Plate-like LiFePO 4 /C composite with preferential (010) lattice plane is successfully prepared via cetyltrimethylammonium bromide (CTAB)-assisted in-situ hydrothermal carbonization synthesis. The structure, morphology and electrochemical property of the as-obtained products are studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution trans mission electron microscopy (HRTEM) and galvanostatic charge–discharge test, respectively. Due to the synergism of uniform carbon coating enhancing transfer efficiency of electrons and preferential growth of (010) lattice plane facilitating diffusion of Li-ions, the LiFePO 4 /C composite shows excellent electrochemical performance. The as-obtained products deliver high-rate capacities of 125 mAh g −1 at 10 C and 110 mAh g −1 at 20 C, while preserving a high tap density of 1.3 g cm −3 . [ABSTRACT FROM AUTHOR]

The general premise for successful archaeologicalin situpreservation in wetlands is that raising the water table will ‘seal the grave’ by preventing oxygen from reaching the deposit. The present review reveals that this may not be the entire picture, as a change in habitat may introduce new plant species that can damage site stratigraphy and artefacts. However, reviews on the types and degree of damage caused by vegetation to archaeological remains preservedin situin wetlands have hitherto only been sporadically treated in the literature. Thus, this paper provides an overview of the adverse effects that various plants species have on the preservation status of wetland archaeology.Disturbance, due to growth of roots and rhizomes of the surrounding soil is denotedcontextual disturbance, whereas deterioration of archaeological remains per se acts by several root-related factors that may be spatially and temporally concomitant. In waterlogged anoxic environments, deterioration is mainly related to (i)preferential growthof roots/rhizomes due to nutrient uptake and lesser soil resistance, (ii)root etchingdue to organic acid exudates, (iii)microbial growthdue to root release of oxygen and labile organic compounds, and/or (iv)precipitation of hydroxidesdue to root release of oxygen. For example, roots of some wetland plants, such as marsh horsetail (Equisetum palustre), have been documented to penetrate archaeological artefacts down toc. 2 m in waterlogged anoxic soils. Here, we demonstrate that cultural heritage site management may unintentionally introduce deep-rooted or exudate aggressive plants by invoking change in hydrological conditions. Moreover, the implementation of biomass energy utilization and agricultural root depth optimization on a worldwide basis stresses the need for more research within root and rhizome impact on archaeological remains in wetlands. In conclusion, the worst-case scenario may bein situ deteriorationinstead ofpreservation, and one essential threat to archaeological wetland sites is the impact of wetland vegetation. [ABSTRACT FROM AUTHOR]