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Lithium is a promising anode material for advanced batteries because of its high capacity and low redox potential. However, its practical use is hindered by nonuniform Li deposition and dendrite formation, leading to safety concerns in Li metal batteries. Our study shows that Ag-based materials enhance the uniformity of Li deposition on Ag-modified Li (AgLi) surfaces, thereby addressing these key challenges. This improvement is due to the strong affinity of Ag for Li, which promotes uniform deposition and dissolution. Additionally, the AgLi surface demonstrated an improved cycling stability, which is crucial for long-term battery reliability. Emphasizing our analytical approach, we utilized comprehensive techniques such as Kelvin probe force microscopy (KPFM) and electrochemical atomic force microscopy (EC-AFM) to locally analyze the electrical properties and unravel the Li deposition/dissolution mechanisms. KPFM analysis provided crucial insights into surface potential variations, while EC-AFM highlighted topographical changes during the Li deposition and dissolution processes, contributing significantly to the development of safer and more efficient Li metal batteries.

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Thin pancake-like neuronal networks cultured on top of a planar microelectrode array have been extensively tried out in neuroengineering, as a substrate for the mobile robot's control unit, i.e., as a cyborg's brain. Most of these attempts failed due to intricate self-organizing dynamics in the neuronal systems. In particular, the networks may exhibit an emergent spatial map of steady nucleation sites ("n-sites") of spontaneous population spikes. Being unpredictable and independent of the surface electrode locations, the n-sites drastically change local ability of the network to generate spikes. Here, using a spiking neuronal network model with generative spatially-embedded connectome, we systematically show in simulations that the number, location, and relative activity of spontaneously formed n-sites ("the vitals") crucially depend on the samplings of three distributions: (1) the network distribution of neuronal excitability, (2) the distribution of connections between neurons of the network, and (3) the distribution of maximal amplitudes of a single synaptic current pulse. Moreover, blocking the dynamics of a small fraction (about 4%) of non-pacemaker neurons having the highest excitability was enough to completely suppress the occurrence of population spikes and their n-sites. This key result is explained theoretically. Remarkably, the n-sites occur taking into account only short-term synaptic plasticity, i.e., without a Hebbian-type plasticity. As the spiking network model used in this study is strictly deterministic, all simulation results can be accurately reproduced. The model, which has already demonstrated a very high richness-to-complexity ratio, can also be directly extended into the three-dimensional case, e.g., for targeting peculiarities of spiking dynamics in cerebral (or brain) organoids. We recommend the model as an excellent illustrative tool for teaching network-level computational neuroscience, complementing a few benchmark models.

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This study investigates the simultaneous decoration of vertically aligned molybdenum disulfide nanostructure (VA-MoS2) with Ag nanoparticles (NPs) and nitrogen functionalization. Nitrogen functionalization was achieved through physical vapor deposition (PVD) DC-magnetron sputtering using nitrogen as a reactive gas, aiming to induce p-type behavior in MoS2. The utilization of reactive sputtering resulted in the growth of three-dimensional silver structures on the surface of MoS2, promoting the formation of silver nanoparticles. A comprehensive characterization was conducted to assess surface modifications and analyze chemical and structural changes. X-ray photoelectron spectroscopy (XPS) showed the presence of silver on the MoS2 surface. Scanning electron microscopy (SEM) confirmed successful decoration with silver nanoparticles, showing that deposition time affects the size and distribution of the silver on the MoS2 surface.

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The formation of uniform, nondendritic seeds is essential to realizing dense lithium (Li) metal anodes and long-life batteries. Here, we discover that faceted Li seeds with a hexagonal shape can be uniformly grown on carbon-polymer composite films. Our investigation reveals the critical role of carbon defects in serving as the nucleation sites for their formation. Tuning the density and spatial distribution of defects enables the optimization of conditions for faceted seed growth. Raman spectral results confirm that lithium nucleation indeed starts at the defect sites. The uniformly distributed crystalline seeds facilitate low-porosity Li deposition, effectively reducing Li pulverization during cycling and unlocking the fast-charging ability of Li metal batteries. At a 1 C rate, full cells using LiNi0.8Mn0.1Co0.1O2 cathode (4.5 mA h cm-2) paired with a lithium anode grown on carbon composite films achieve a 313% improvement in cycle life compared to baseline cells. Polymer composites with carbonaceous materials rich in defects are scalable, low-cost substrates for high-rate, high-energy-density batteries.

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Aqueous Zn-metal battery is considered as a promising energy-storage system. However, uncontrolled zinc dendrite growth is the main cause of short-circuit failure in aqueous Zn-based batteries. One of the most efficient and convenient strategies to alleviate this issue is to introduce appropriate zincophilic nucleation sites to guide zinc metal deposition and regulate crystal growth. Herein, this work proposes Bi2O3/Bi nanosheets anchored on the cell wall surface of the 3D porous conductive host as the Zn deposition sites to modulate Zn deposition behavior and hence inhibit the zinc dendrite growth. Density functional theory and experimental results demonstrate that Bi2O3 has a super zinc binding energy and strong adsorption energy with zinc (002) plane, as a super-zincophilic nucleation site, which results in the deposition of zinc preferentially along the horizontal direction of (002) crystal plane, fundamentally avoids the formation of Zn dendrites. Benefiting from the synergistic effect Bi2O3/Bi zincophilic sites and 3D porous structure in the B-BOGC host, the electrochemical performance of the constructed Zn-based battery is significantly improved. As a result, the Zn anode cycles for 1500 cycles at 50 mA cm-2 and 1.0 mAh cm-2. Meanwhile, the Zn@B-BOGC//MnO2 full cell can operate stably for 2000 cycles at 2.0 A g-1.

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Tricalcium silicate (C3S) as a binder material has a decisive influence on the processes of hardening and strength gain of cements and concretes. One of the promising directions is the introduction of dispersed additives into cement mixtures, which allow micro-level control of the composition of hydration products and change the dynamics of the structure formation of cement stone. In this paper, the effect of a microdisperse ettringite additive on the kinetics of the hydration and hardening process of tricalcium silicate was studied. It was shown that ettringite crystals selectively adsorb Ca2+ and OH- ions from a saturated solution of calcium hydroxide, which contributes to the formation of hydrosilicate nuclei on their surface during cement hydration. Hydration of C3S in the presence of ettringite proceeds more intensively; the addition of ettringite contributes to an increase in the content of calcium hydrosilicates in hydration products at the initial stage of the process. Addition of 10 wt.% ettringite to C3S reduces the induction period of the beginning of the main phase of heat release by around two times and increases the amount of heat released on the 1st day of hydration by 15% compared to the control sample. According to electron microscopy data, it was found that during the first hours of hydration of modified C3S, a significant number of nuclei of fibrous particles of calcium hydrosilicates with sizes of 0.2-2 microns were formed on the surface of ettringite crystals. According to the results of kinetic modeling of the setting process of cement pastes using the Avrami-Erofeyev model, it was shown that in the presence of the addition of microcrystals of ettringite, the setting rate is characterized by a slowdown in nucleation, whereas for a sample without an additive, this process proceeds with an acceleration of the formation of solid-phase nuclei. Based on the comparison of kinetic results and mechanical measurements, it is concluded that needle crystals of ettringite during C3S hydration and cement stone hardening are preformed centers for the growth of hydrosilicate nuclei, and they also act as a reinforcing filler, increasing the bending strength of modified samples. The results of the work can be used in practice in the development of methods for controlling the processes of hydration and hardening of cements, as well as for controllable structure formation of cement stone which is important in particular for 3D printing of building products and constructions.

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Zinc metal has considerable potential as a high-energy anode material for aqueous batteries due to its high theoretical capacity and environmental friendliness. However, dendrite growth and parasitic reactions at the electrode/electrolyte interface remain two serious problems for the Zn metal anode. Here, the heterostructured interface of ZnO rod array and CuZn5 layer is fabricated on the Zn substrate (ZnCu@Zn) to address these two issues. The zincophilic CuZn5 layer with abundant nucleation sites ensures the initial uniform Zn nucleation process during cycling. Meanwhile, the ZnO rod array grown on the surface of the CuZn5 layer can guide the subsequent homogeneous Zn deposition via spatial confinement and electrostatic attraction effects, leading to the dendrite-free Zn electrodeposition process. Consequently, the derived ZnCu@Zn anode exhibits an ultra-long lifespan of up to 2500 h with symmetric cells at the current density and capacity of 0.5 mA cm-2 /0.5 mA h cm-2 . Besides, a remarkable cyclability (75% retention for 2500 cycles at 2 A g-1 ) is achieved in the ZnCu@Zn||MnO2 full cell with a capacity of 139.7 mA h g-1 . This heterostructured interface with specific functional layers provides a feasible strategy for the design of high-performance metal anodes.

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Recently, microbially induced carbonate precipitation (MICP) has shown potent potential in the field of civil engineering. The calcium carbonate crystals produced by bacteria during the MICP process play a central role in sticking the soil. However, the morphological changes of calcium carbonate crystals in this process and the mechanical performance of soil in the corresponding stages have not been clearly explored. In this paper, the alterations in the morphology of calcium carbonate crystals were continuously observed via scanning electron microscopy during the MICP process in one week, and the mechanical changes of the samples were monitored every day, so as to reveal the relationship between the morphology of calcium carbonate crystals and the mechanical performance of the samples. The results show that the calcium carbonate crystals undergo a gradual change from ellipsoid to rhombic at the 72nd hour. The mechanical properties of both were greatly improved, among which the compressive strength was increased by 2.78 times compared with the previous time point, and the flexure strength was increased by 2.57 times; this time point was also the time when calcite appears. In addition, we found direct evidence on the first day that bacteria act as the nucleation site of calcium carbonate formation. The above findings have certain guiding significance for the in-depth understanding of the internal microscopic changes of MICP and the influence of calcium carbonate morphology on sample mechanics.

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This research aimed to evaluate chitosan (CTS) and carboxymethyl chitosan (CMCS) as polysaccharides that could mimic the role of bacterial extracellular polymeric substance (EPS) in the biomineralization process through bionic experiments. The introduction of COOH resulted in higher calcium precipitation efficiency of CMCS (65.07%) than CTS (55.66%). CaCO3 nucleation on the surface of CTS and CMCS was triggered through the binding of Ca2+ to NH2, OH, COOH and NHCOCH3 groups. Moreover, the experiment of polysaccharides mediated biomineralization was conducted. The maximum calcium precipitation efficiency reached 96.07% with the addition of 0.15% CMCS. Combining the characterization results, the synergetic mineralization mechanisms between polysaccharides and bacteria were proposed. Among them, bacterial metabolic by-products (alkalinity), active groups and adhesion of polysaccharides played a significant role. This work provides a reference for further understanding of the biomineralization mechanism, and gives a new insight into the intensified strategies of MICP technology.

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Lithium (Li) has garnered considerable attention as an alternative anodes of next-generation high-performance batteries owing to its prominent theoretical specific capacity. However, the commercialization of Li metal anodes (LMAs) is significantly compromised by non-uniform Li deposition and inferior electrolyte-anode interfaces, particularly at high currents and capacities. Herein, a hierarchical three-dimentional structure with CoSe2 -nanoparticle-anchored nitrogen-doped carbon nanoflake arrays is developed on a carbon fiber cloth (CoSe2 -NC@CFC) to regulate the Li nucleation/plating process and stabilize the electrolyte-anode interface. Owing to the enhanced lithiophilicity endowed by CoSe2 -NC, in situ-formed Li2 Se and Co nanoparticles during initial Li nucleation, and large void space, CoSe2 -NC@CFC can induce homogeneous Li nucleation/plating, optimize the solid electrolyte interface, and mitigate volume change. Consequently, the CoSe2 -NC@CFC can accommodate Li with a high areal capacity of up to 40 mAh cm-2 . Moreover, the Li/CoSe2 -NC@CFC anodes possess outstanding cycling stability and lifespan in symmetric cells, particularly under ultrahigh currents and capacities (1600 h at 10 mA cm-2 /10 mAh cm-2 and 5 mA cm-2 /20 mAh cm-2 ). The Li/CoSe2 -NC@CFC//LiFePO4 full cell delivers impressive long-term performance and favorable flexibility. The developed CoSe2 -NC@CFC provides insights into the development of advanced Li hosts for flexible and stable LMAs.

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Utilization of natural clay minerals for the treatment of heavy metal cadmium contamination is appealing as the affordable and readily accessible raw materials. However, the low reactivity of natural serpentine limits its practical application for Cd removal. In the present study, mechanochemical activation of antigorite-type serpentine (SP) as example was introduced to enhance its removal capacity for heavy metal of cadmium high enough for practical use. It was found ball-milling at 600 rpm for 60 min for antigorite resulted in the increased release of hydroxyl group to facilitate the precipitation of Cd2+, giving a capacity of 27.4 mg/g for the treatment of 100 mg/L Cd2+ for 120 min at room temperature, which was 10 times higher than that of the pristine antigorite (2.5 mg/g). More significantly, magnesium sulfate (MgSO4, MS) was introduced for the first time to process antigorite, thus to form MgSO4-incorporated antigorite. As a result, the removal capacity for Cd2+ was dramatically increased to 239.7 mg/g with the equal antigorite dosage (the molar ratio of SP/MS = 1:0.5), which is also much higher than the other reported clay minerals. Results showed that, MgSO4 incorporation promoted the reactivity of antigorite and provided numerous SO42- active sites, which allowed the heterogeneous nucleation of basic cadmium sulfate (CdSO4·3.5 Cd(OH)2·xH2O) precipitate on antigorite, therefore not requiring high alkalinity support as the conventional formation of cadmium hydroxide does. Correspondingly, under the new mechanism, the Cd precipitation could take place in a wide pH range, even from pH 3.0, which was a rarely reported phenomenon happening on natural minerals. Based on these findings, this study demonstrated the effectiveness of mechanochemical incorporation of sulfate for enhancing the Cd2+ removal capacity of serpentine, as well as the high efficiency of new pathway for Cd2+ precipitation. Moreover, the potential of low-cost serpentine as alternative stabilizers for the highly-effective remediation of heavy metal contamination may be expected.

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Uncontrolled growth of Zn dendrites and side reactions are the major restrictions for the commercialization of Zn metal anodes. Herein, we develop a TiOx /Zn/N-doped carbon inverse opal (denoted as TZNC IO) host to regulate the Zn deposition. Amorphous TiOx and Zn/N-doped carbon can serve as the zincophilic nucleation sites to prevent the parasitic reactions. More importantly, the highly ordered IO host homogenizes the local current density and electric field to stabilize Zn deposition. Furthermore, the three-dimensional open networks could regulate Zn ion flux to enable stable cycling performance at large current densities. Owing to the abundant zincophilic sites and the open structure, granular Zn deposits could be realized. As expected, the TZNC IO host guarantees the steady Zn plating/stripping with a long-term stability over 450 h at the current density of 1 mA cm-2 . As a proof-of-concept demonstration, a TZNC@Zn||V2 O5 full cell shows long lifespan over 2000 cycles at 5.0 A g-1 .

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The growth of lithium (Li) dendrites and the huge volume change are the critical issues for the practical applications of Li-metal anodes. In this work, a spatial control strategy is proposed to address the above challenges using lotus-root-like Ni-Co hollow prisms@carbon fibers (NCH@CFs) as the host. The homogeneously distributed bimetallic Ni-Co particles on the N-doped carbon fibers serve as nucleation sites to effectively reduce the overpotential for Li nucleation. Furthermore, the 3D conductive network can alter the electric field. More importantly, the hierarchical lotus-root-like hollow fibers provide sufficient void space to withstand the volume expansion during Li deposition. These structural features guide the uniform Li nucleation and non-dendritic growth. As a result, the NCH@CFs host enables a very stable Li metal anode with a low voltage hysteresis during repeated Li plating/stripping for 1200 h at a current density of 1 mA cm-2 .

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The practical applications of Li metal batteries (LMBs) have long been limited by the obstacles of low Coulombic efficiency (CE) and formation of dendrites on Li metal electrode. Herein, we demonstrated the synthesis of a novel three-dimensional (3D) nanostructured skeleton substrate composed of nitrogen-doped hollow carbon fiber/carbon nanosheets/ZnO (NHCF/CN/ZnO) using 2-methylimidazole (2-MIZ)-coated 3D cloth as a scaffold. The mechanism of formation of this novel hierarchical structure was investigated. The multilayered hierarchical structure and abundant lithiophilic nucleation sites of the substrate provide a stable environment for the deposition and stripping of lithium metal, thus preventing the generation of lithium dendrites. Consequently, the lithium anode based on the NHCF/CN/ZnO current collector demonstrated an excellent Coulombic efficiency of 96.47% after 400 cycles at 0.5 mA cm-2. The prepared NHCF/CN/ZnO/Li electrode also showed outstanding cycling performance of over 800 h and an ultralow voltage hysteresis of less than 30 mV in a symmetric cell at 5 mA cm-2 and 5 mAh cm-2. Even at a high loading of the cathode with 10.4 mg cm-2, the full cell of NHCF/CN/ZnO/Li anode with LiFePO4 can also work very well. Our work offers a path toward the facial preparation of 3D hierarchical structure for high-performance lithium metal batteries.

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The nonuniform nucleation of lithium (Li) leads to dendritic behavior and formation of dead Li, which seriously hinders the practical application of Li metal batteries. Here, atomic layer deposition (ALD) is used to deposit uniform and conformal ZnO coating (at a low content of 5.96%) on carbon fibers to form a free-standing framework Li host material without uncontrollable dendrites. Compared with the liquid deposition process, the ALD method can achieve homogeneous and conformal ZnO coating and excellent lithiophilicity of the carbon fiber, guiding molten Li infusion into the carbon fiber skeleton to obtain the Li/C composite electrode with a flat surface, thereby minimizing the effective current density. More importantly, the converted LiZn alloy will serve as uniform and numerous nucleation sites for Li and guide synchronous growth of the Li metal along carbon fibers, displaying a dendrite-free morphology after large-current and long-term deposition/dissolution cycling. Therefore, the ALD ZnO-modified carbon fiber/Li exhibits significantly better cycle and rate performances than the liquid deposition ZnO-modified carbon fiber/Li composite anode. The electrodes display an ultralong lifespan up to 400 cycles at 3.0 mA/cm2, as well as a high rate performance (with a deposition overpotential of 338 mV at 25.0 mA/cm2) at a high Li deposition areal capacity of 5.0 mA h cm-2.

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The reducing and capping sites along with their local structure impact photo properties of the red bovine serum albumin-capped Au nanocluster (BSA-AuNC), however, they are hard to identify. We developped a workflow and relevant techniques using mass spectrometry (MS) to identify the reducing and capping sites of BSA-AuNCs involved in their formation and fluorescence. Digestion without disulfide cleavages yielded an Au core fraction exhibiting red fluorescence and [AunSm] ion signals and a non-core fraction exhibiting neither of them. The core fraction was identified to mainly be comprised of peptides containing cysteine residues. The fluorescence and [AunSm] signals were quenched by tris(2-carboxyethyl)phosphine, confirming that disulfide groups were required for nanocluster stabilization and fluorescence. By MS sequencing, the disulfide pairs, C75-C91/C90-C101 in domain IA, C315-C360/C359-C368 in domain IIB, and C513-C558/C557-C566 in domain IIIB, were identified to be main capping sites of red AuNCs. Peptides containing oxidized cysteines (sulfinic or cysteic acid) were identified as reducing sites mainly in the non-core fraction, suggesting that disulfide cleavages by oxidization and conformational changes contributed to the subsequent growth of nanoclusters at nearby intact disulfide pairs. This is the first report on precise identification of the reducing and capping sites of BSA-AuNCs.

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Environmental scanning electron microscopy (ESEM) is a broadly utilized nanoscale inspection technique capable of imaging wet or insulating samples. It extends the application of conventional scanning electron microscopy (SEM) and has been extensively used to study the behavior of liquid, polymer, and biomaterials by allowing for a gaseous environment. However, the presence of gas in the chamber can severely degrade the image resolution and contrast. This typically limits the ESEM operating pressure below 1000 Pa. The dynamic interactions, which require even-higher sensitivity and resolution, are particularly challenging to resolve at high-pressure conditions. Here, we present an enhanced ESEM technique using phase reconstruction to extend the limits of the ESEM operating pressure while improving the image quality, which is useful for sensing weak scattering from transparent or nanoscale samples. We applied this method to investigate the dynamics of condensing droplets, as an example case, which is of fundamental importance and has many industrial applications. We visualized dynamic processes such as single-droplet growth and droplet coalescence where the operating pressure range was extended from 1000 to 2500 Pa. Moreover, we detected the distribution of nucleation sites on the nanostructured surfaces. Such nanoscale sensing has been challenging previously due to the limitation of resolution and sensitivity. Our work provides a simple approach for high-performance ESEM imaging at high-pressure conditions without changes to the hardware and can be widely applied to investigate a broad range of static and dynamic processes.

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Lithium metal is one of the most promising anode materials for high-energy-density Li batteries. However, low stability caused by dendrite growth and volume change during cycling hinders its practical application. Herein, we report an ingenious design of bio-inspired low-tortuosity carbon with tunable vertical micro-channels to be used as a host to incorporate nanosized Sn/Ni alloy nucleation sites, which can guide Li metal's plating/stripping and meanwhile accommodate the volume change. The pore sizes of the vertical channels of the carbon host can be regulated to investigate the structure-performance correlation. After compositing Li, the bio-inspired carbon host with the smallest pore size (∼14 µm) of vertical channels exhibits the lowest overpotential (∼18 mV at 1 mA cm-2), most stable tripping/plating voltage profiles, and best cycling stability (up to 500 cycles) in symmetrical cells. Notably, the carbon/Li composite anode is more rewarding than Li foil when coupled with LiFePO4 in full cells, exhibiting a much lower polarization effect, better rate capability and higher capacity retention (90.6% after 120 cycles). This novel bio-inspired design of a low-tortuosity carbon host with nanoalloy coatings may open a new avenue for fabricating advanced Li-metal batteries with high performance.

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To achieve high-quality perovskite solar cells (PSCs), the morphology and carrier transportation of perovskite films need to be optimized. Herein, C60 is employed as nucleation sites in PbI2 precursor solution to optimize the morphology of perovskite films via vapor-assisted deposition process. Accompanying the homogeneous nucleation of PbI2, the incorporation of C60 as heterogeneous nucleation sites can lower the nucleation free energy of PbI2, which facilitates the diffusion and reaction between PbI2 and organic source. Meanwhile, C60 could enhance carrier transportation and reduce charge recombination in the perovskite layer due to its high electron mobility and conductivity. In addition, the grain sizes of perovskite get larger with C60 optimizing, which can reduce the grain boundaries and voids in perovskite and prevent the corrosion because of moisture. As a result, we obtain PSCs with a power conversion efficiency (PCE) of 18.33% and excellent stability. The PCEs of unsealed devices drop less than 10% in a dehumidification cabinet after 100 days and remain at 75% of the initial PCE during exposure to ambient air (humidity > 60% RH, temperature > 30 °C) for 30 days.

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The microtubule cytoskeleton is critically important for spatio-temporal organization of eukaryotic cells. The nucleation of new microtubules is typically restricted to microtubule organizing centers (MTOCs) and requires γ-tubulin that assembles into multisubunit complexes of various sizes. γ-Tubulin ring complexes (TuRCs) are efficient microtubule nucleators and are associated with large number of targeting, activating and modulating proteins. γ-Tubulin-dependent nucleation of microtubules occurs both from canonical MTOCs, such as spindle pole bodies and centrosomes, and additional sites such as Golgi apparatus, nuclear envelope, plasma membrane-associated sites, chromatin and surface of pre-existing microtubules. Despite many advances in structure of γ-tubulin complexes and characterization of γTuRC interacting factors, regulatory mechanisms of microtubule nucleation are not fully understood. Here, we review recent work on the factors and regulatory mechanisms that are involved in centrosomal and non-centrosomal microtubule nucleation.

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