Silicon Carbon Research Articles

An experimental study on the heat transfer performance of a radiator using MWCNT-SiO2 hybrid nanofluid

ABSTRACT The study aims to investigate the effect of nanofluids on heat transfer through experimentation. To prepare the nanofluids, water, commonly used in radiator cooling systems, served as the base liquid. Multi-walled carbon nanotubes (MWCNT) and silicon dioxide (SiO2) nanoparticles were added at weight concentrations of 0.1%, 0.2%, 0.3%, and 0.4%, with two different flow rates tested. Sodium dodecyl sulfate (SDS) surfactant was used to prevent the nanoparticles from agglomerating. After visually observing the hybrid nanocoolant, it was found that SDS as a surfactant prevented sedimentation and maintained stability for two weeks. Furthermore, STEM imaging demonstrated that spherical SiO2 particles evenly distributed throughout the tube-shaped CNTs improved the fluid’s thermophysical properties regarding heat transfer. Heat transfer improvements were assessed with water experiments. The findings indicate that greater nanoparticle weight concentration promotes heat transfer. The most significant improvement in thermal conductance (UxA) was recorded as 28% in the case of 0.4 wt.% MWCNT water-based nanofluid at 0.034 kg/s flow rate as against water. The economical performance of a nanoparticle-containing cooling system was gauged for a natural gas-powered engine.

Field-Frequency Variation during Plasma-Chemical Deposition of Silicon–Carbon Films as a Method for Their Structural Modification

Field-Frequency Variation during Plasma-Chemical Deposition of Silicon–Carbon Films as a Method for Their Structural Modification

Effect of thermo-mechanical and low-cycle preloading on the strength of carbon fiber-reinforced ceramic matrix composites

Fiber-reinforced ceramic matrix composites (CMCs) exhibit excellent thermo-mechanical properties including outstanding resistance against damage and fatigue. Some CMCs show occasionally even a strength enhancement after fatigue, often interpreted with relieve of internal stresses and interfacial degradation. This study reports the influence of low-cycle thermo-mechanical preloading on the bending and tensile strength of carbon fiber-reinforced silicon carbon (C/C-SiC). For this purpose two C/C-SiC materials with the same fiber architecture but different assumed internal stress states were subjected to single and cyclic mechanical preloads up to 90% of their ultimate strength level at room temperature and at 350 °C. Statistical evaluations of the experiments show that the ultimate strength values were surprisingly unchanged after preloading. The results are discussed regarding the thermal residual stresses (TRS).

Ab initio study of Li-shrouded Si-doped [formula omitted]-Graphyne nanosheet as propitious anode in Li-ion batteries

Li-ion batteries (LIBs) have become a house-hold name in the energy-storage research community in the wake of their noteworthy attributes. With increasing energy demands, the urgency to develop high performance LIBs is also rising rapidly which has compelled the researchers to design and fabricate new high capacity materials. Bearing that in mind, we have investigated a carbon–silicon based anode, i.e. Si-doped γ-Graphyne (SiG) nanolayer for its applicability as LIB electrode. Carbon and Silicon are two complementary choices for anode material due to the reason that the weakness of one is complemented by the other i.e. the extensive volume changes of Si anodes is compensated by the stable carbon matrix and the lower Li affinity of carbon is complemented by large capacities of Si anode. The Density Functional Theory (DFT) based studies reveal that SiG nanolayer has a dynamically and thermally stable structure with reliable mechanical properties. Density of states (DOS) calculation substantiates the good conductivity of the nanolayer. The binding energy of the Li atom (adatom) is −1.33 eV resulting from a charge transfer of 0.88e from Li to the nanolayer. The SiG anode achieved a specific capacity of 1005.05 mAhg−1 (almost 2.7 times the Graphite anode used in commercial LIBs). Climbing Image-Nudged Elastic Band (CI-NEB) calculations depict an easy migration of the adatoms through the anode with an energy barrier of 0.67 eV having diffusion coefficient (D) as 8.91 × 10−14 cm2/s. A low working voltage of 0.44 V is obtained advocating a safe operation and good cyclability. So, the theoretical investigation presents favorable outcomes for Si-doped γ-Graphyne to be applicable as a progressive anode in next-generation LIBs.

Barium in seawater: dissolved distribution, relationship to silicon, and barite saturation state determined using machine learning

Abstract. Barium is widely used as a proxy for dissolved silicon and particulate organic carbon fluxes in seawater. However, these proxy applications are limited by insufficient knowledge of the dissolved distribution of Ba ([Ba]). For example, there is significant spatial variability in the barium–silicon relationship, and ocean chemistry may influence sedimentary Ba preservation. To help address these issues, we developed 4095 models for predicting [Ba] using Gaussian process regression machine learning. These models were trained to predict [Ba] from standard oceanographic observations using GEOTRACES data from the Arctic, Atlantic, Pacific, and Southern oceans. Trained models were then validated by comparing predictions against withheld [Ba] data from the Indian Ocean. We find that a model trained using depth, temperature, and salinity, as well as dissolved dioxygen, phosphate, nitrate, and silicate, can accurately predict [Ba] in the Indian Ocean with a mean absolute percentage deviation of 6.0 %. We use this model to simulate [Ba] on a global basis using these same seven predictors in the World Ocean Atlas. The resulting [Ba] distribution constrains the Ba budget of the ocean to 122(±7) × 1012 mol and reveals oceanographically consistent variability in the barium–silicon relationship. We then calculate the saturation state of seawater with respect to barite. This calculation reveals systematic spatial and vertical variations in marine barite saturation and shows that the ocean below 1000 m is at equilibrium with respect to barite. We describe a number of possible applications for our model outputs, ranging from use in mechanistic biogeochemical models to paleoproxy calibration. Our approach demonstrates the utility of machine learning in accurately simulating the distributions of tracers in the sea and provides a framework that could be extended to other trace elements. Our model, the data used in training and validation, and global outputs are available in Horner and Mete (2023, https://doi.org/10.26008/1912/bco-dmo.885506.2).

DFT study of SCN− adsorption effect on structural and electronic properties of Si12C12 fullerenes

Utilizing density functional theory (DFT) calculations, the adsorption characteristics and electronic structure of thiocyanate anion (SCN−) through nitrogen and sulfur heads upon the Si12C12 surface were investigated by the B3LYP functional and 6–31 + G** standard basis set. The results express that the covalent interaction of SCN− through the nitrogen head (−3.08 eV) is stronger in comparison with the sulfur head of SCN− (−2.32 eV) to the fullerene surface. Additionally, the interaction of two SCN− through nitrogen head has weaker surface adsorption on the silicon-carbon (SiC) atom (−1.27 eV) in comparison with the SiSi atom (−2.78 eV) of Si12C12 fullerene. The influence of SCN− adsorption on the Si12C12 surface was characterized by the infrared (IR) absorption spectrum. A significant orbital hybridization between SCN− and Si12C12 fullerenes occurred during the adsorption process, according to the computed density of states (DOS). According to the analysis of binding energy, energy gap, and dipole moment, Si12C12 fullerene can be applied to SCN− removal applications. Based on the thermodynamic parameters, the negative Gibbs free energy (ΔG) and enthalpy change (ΔH) values confirmed that the SCN− adsorption by the nitrogen heads on the Si12C12 surface was spontaneous and exothermic.

MICROSTRUCTURAL AND CORROSION ANALYSIS OF CROWN PINION WITH VARIOUS COMPOSITIONS OF HIGH CARBON STEEL AND SILICON CARBIDE MATERIALS

The pinion and crown are key components in an automobile’s transmission system. The surface characteristics of high-carbon steel have a major effect on differential gear action. As a result, gear damages and increased downtime for repairs are experienced over time. To address this issue, manufacturers have started using alternative materials such as aluminium alloys and composites to improve the durability and efficiency of the transmission system. Engineers can now adjust the design of crown and pinion gears for best performance thanks to developments in computer-aided design and simulation tools. This has led to the development of more compact and lightweight transmission systems that offer better fuel efficiency and acceleration. However, these innovations come at a cost, as they require specialized manufacturing processes and materials that can be expensive. Nevertheless, the benefits of improved transmission systems are clear, as they can significantly enhance the driving experience while reducing maintenance costs over time. As technology continues to evolve, we can expect further improvements in material design that will further enhance crown pinion performance and reliability. To overcome these failures and increase the material’s life, high-carbon steel is preferred. In this study, high-carbon steel composites with various material proportions (100% to 0%, 99% to 1%, and 97.5% to 2.5% of high-carbon steel, and silicon carbide, respectively) are experimentally investigated and evaluated for better structural strength and surface behavior of the crown pinion. The crown pinion is thoroughly analyzed using salt spray corrosion testing and X-ray diffraction analysis. According to the results, the proportion of 97.5% high carbon steel with 2.5% silicon carbide has better surface properties than the other proportions, and it is also recommended to make the crown pinion for future uses.

Influence of different anode active materials and blends on the performance and fast-charging capability of lithium-ion battery cells

To further extent the driving range of battery electric vehicles, an increase of the energy density of lithium-ion battery cells is necessary. One way to increase the energy density is the use of high-capacity electrodes. The challenges for this kind of electrodes are transport limitations, like the long lithium-ion diffusion path to the layers near the substrate of the electrode, leading to performance degradation during cycling. To get a better understanding on how the material selection influences the battery cell performance, various active materials (graphite, silicon, and hard carbon) are investigated, both, pure and in blends and the relation between material, structure and performance is studied. On material level pure silicon active material has a very high electric resistance compared to carbon-based materials. Nevertheless, on electrode level, the high gravimetric energy density, and the round-shaped particle morphology of silicon result into a lower tortuosity and layer thickness, hence, ionic resistance of the electrode. With respect to cell performance, the ionic resistance seems to have a greater impact compared to the charge-transfer and electric resistance. Therefore, silicon-based electrodes show the best performance.

Influence of carbon target power on the tribological and electrochemical properties of NbMoSiC composite films in seawater

Because the wear and corrosion of marine engineering equipment will cause huge economic losses to enterprises every year, thus it is necessary to develop advanced protective films to ensure the normal operation of marine equipment. Here NbMoSiC composite films are deposited using DC magnetron sputtering in an argon atmosphere through varying the carbon target sputtering power, and their microstructure and mechanical properties are investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS)，Raman spectroscopy and dynamic ultra-micro hardness tester, respectively. The tribological properties of the films in air and artificial seawater are determined by a reciprocating ball-on-disc tester, while the electrochemical properties of the films in seawater were evaluated by an electrochemical workstation. The results demonstrate that the presence of Nb2C, MoSi2, free silicon, and amorphous carbon (a-C) in the NbMoSiC composite films. Particularly, Sample C250, featuring a carbon content of 35.02 at.%, exhibits higher hardness, elastic modulus, excellent wear resistance, and superior corrosion resistance. However, a further increase in carbon target sputtering power leads to escalated surface roughness and microchannels, ultimately resulting in reduced wear and corrosion performance. Electrochemical analysis reveal that the strong synergistic effect of amorphous carbon as well as the metal oxide phase formed on the surface significantly enhanced the corrosion resistance of the film in artificial seawater with a corrosion current density as low as 1.8 × 10−8 A/cm2.

A Stress Self-Adaptive Silicon/Carbon "Ordered Structures" to Suppress the Electro-Chemo-Mechanical Failure: Piezo-Electrochemistry and Piezo-Ionic Dynamics.

Construction of ordered structures that respond rapidly to environmental stimuli has fascinating possibilities for utilization in energy storage, wearable electronics, and biotechnology. Silicon/carbon (Si/C) anodes with extremely high energy densities have sparked widespread interest for lithium-ion batteries (LIBs), while their implementation is constrained via mechanical structure deterioration, continued growth of the solid electrolyte interface (SEI), and cycling instability. In this study, a piezoelectric Bi0.5 Na0.5 TiO3 (BNT) layer is facilely deposited onto Si/C@CNTs anodes to drive piezoelectric fields upon large volume expansion of Si/C@CNTs electrode materials, resulting in the modulation of interfacial Li+ kinetics during cycling and providing an electrochemical reaction with a mechanically robust and chemically stable substrate. In-depth investigations into theoretical computation, multi-scale in/ex situ characterizations, and finite element analysis reveal that the improved structural stability, suppressed volume variations, and controlled ion transportation are responsible for the improvement mechanism of BNT decorating. These discoveries provide insight into the surface coupling technique between mechanical and electric fields to control the interfacial Li+ kinetics behavior and improve structural stability for alloy-based anodes, which will also spark a great deal attention from researchers and technologists in multifunctional surface engineering for electrochemical systems.

Synthesis and Characterization of Silicon–Carbon Powder and Its Resistance to Electron Irradiation

The issue of crystallization of silicon oxide at low temperatures is a topical issue for the electronics of the future. Organosilicon oligomers and polymers are “ideal” sources for obtaining ultrapure silicon ceramics and silicon nanoparticles. This paper presents the results of the synthesis of highly dispersed silicon-carbon powder from an organohydrosiloxane oligomer and the method for increasing its crystallinity at low temperatures. The diffraction pattern of the resulting powder corresponds to the amorphous–crystalline state of the components in this material, as evidenced by two intense and broadened amorphous halos in the region of Bragg angles 2θ = 7–11° and 18–25°. The resulting silicon–carbon powder was subjected to electron irradiation (E = 10 MeV; D = 106–107 Gy). This paper presents the data on the changes in powder properties via IR-Fourier spectroscopy, X-ray phase analysis, and scanning electron microscopy. Irradiation with fast electrons with an absorbed dose of 106 Gy leads to a slight crystallization of the amorphous SiO2 phase. An increase in the absorbed dose of fast electrons from D = 106 to D = 107 Gy leads to the opposite effect. An amorphization of silica is observed. This study showed the possibility of the crystallization of a silicon–carbon powder without a significant increase in temperature, acting only with electron irradiation. It is necessary to continue further research on expanding the boundaries of the optimal doses of absorbed radiation from fast electrons in order to achieve the maximum effect of the crystallization of silicon–carbon powder.

Development and Characterization of Nano-Ink from Silicon Carbide/Multi-Walled Carbon Nanotubes/Synthesized Silver Nanoparticles for Non-Enzymatic Paraoxon Residuals Detection.

The ongoing advancement in the synthesis of new nanomaterials has accelerated the rapid development of non-enzymatic pesticide sensors based on electrochemical platforms. This study aims to develop and characterize Nano-ink for applying organophosphorus pesticides using paraoxon residue detection. Multi-walled carbon nanotubes, silicon carbide, and silver nanoparticles were used to create Nano-ink using a green synthesis process in 1:1:0, 1:1:0.5, and 1:1:1 ratios, respectively. These composites were combined with chitosan of varying molecular weights, which served as a stabilizing glue to keep the Nano-ink employed in a functioning electrode stable. By using X-ray powder diffraction, Raman spectroscopy, energy dispersive X-ray spectroscopy, and a field emission scanning electron microscope, researchers were able to examine the crystallinity, element composition, and surface morphology of Nano-ink. The performance of the proposed imprinted working electrode Nano-ink was investigated using cyclic voltammetry and differential pulse voltammetry techniques. The Cyclic voltammogram of Ag NPs/chitosan (medium, 50 mg) illustrated high current responses and favorable conditions of the Nano-ink modified electrode. Under the optimized conditions, the reduction currents of paraoxon using the DPV techniques demonstrated a linear reaction ranging between 0.001 and 1.0 µg/mL (R2 = 0.9959) with a limit of detection of 0.0038 µg/mL and a limit of quantitation of 0.011 µg/mL. It was concluded that the fabricated Nano-ink showed good electrochemical activity for non-enzymatic paraoxon sensing.

A real-time monitoring of pre-overcharge in high‑nickel lithium ion batteries via plasma emission spectroscopy

Using the calibration-free atomic spectroscopic technique on lithium (Li) I with its wavelengths at 610.35, 610.65, and 670.79 nm, Li ion signals at varying state of charge (SOC) from high‑nickel (>88 %) batteries with NCA (Ni-Co-Al) cathode and SCN (silicon carbon nanocomposite) anode are detected in real-time (<3 s). The laser-induced plasma spectroscopy (LIPS) revealed that moderate changes in the concentrations of Li and metals (Ni, Co, and Al) during the normal charging underwent an abrupt concentration change in Li as the SOC reached above 75 %. Verified by using SEM-EDS (Scanning Electron Microscopy-Energy Dispersive Spectrometer), this sudden decrease of Li ions in cathode is deemed as being indicative of the state of overcharge. The present work is aimed at developing a new opto-chemical SOC sensor while the experimental set up offers a new method for detecting the state of pre-overcharge in nickel-rich Li-ion batteries.

Recent progress on the electromagnetic wave absorption of one-dimensional carbon-based nanomaterials

The rapid development of electronic information technology and the use of high-power electrical equipment have led to the increasingly serious problem of electromagnetic interference (EMI). Therefore, it is of great significance to study electromagnetic wave absorbing (EWA) materials with good absorbing properties. Compared with other wave absorbing materials, carbon-based nanomaterials such as silicon carbide (SiC), carbon nanotube (CNT), carbon nanowire (CNW) and carbon nanofiber (CNF) have the advantages of low density, large specific surface area/aspect ratio and excellent dielectric properties, which make them stand out. However, impedance mismatch caused by high conductivity and a single microwave loss mechanism seriously affect the absorption performance. In order to overcome the above shortcomings, surface modification, component control, structural design and other methods have been widely used in EWA materials in recent years to improve their absorption performance. In this review, we introduce the mechanism of microwave absorption and summarizes the research progress of one-dimensional carbon based nanomaterials and their composites. The preparation methods and microwave absorption properties of one-dimensional carbon based nanocomposites with different components, morphologies, and microstructures were discussed in detail. Finally, the challenges and future development prospects of one-dimensional carbon based nanomaterials were summarized, providing reference for the development of high-performance microwave absorbing materials.

Adhesion Strength of Al, Cr, In, Mo, and W Metal Coatings Deposited on a Silicon–Carbon Film

For the first time, the possibility of creating a multilayer system metal (Al, Cr, In, Mo, and W) silicon–carbon coating was studied. A silicon–carbon film was synthesized from a polyorganosiloxane polymer containing an active Si–O siloxane group. Due to the use of furnace pyrolysis, in which the purge gas continuously removes the polymer thermal degradation products from the system, it was possible to reduce the film formation temperature to 300 °C. According to the energy dispersive analysis data, silicon–carbon film has the following composition: C—34.85 wt%, O—42.02 wt%, and Si—23.13 wt%. Metallic coatings of Al, Cr, In, Mo, and W on a silicon–carbon substrate were obtained by vacuum magnetron sputtering. The metallic coatings were evaluated by SEM as well as by X-ray phase analysis. The adhesion strength of metallic coatings to the silicon–carbon substrate was assessed by scratching under continuously increasing load with a Rockwell C Diamond Indenter. At the same time, the friction coefficient was recorded at the corresponding value of load on the indenter. The adhesive strength of metals with the silicon–carbon substrate increases in the sequence W, Mo, In, Al, and Cr.

Optimization of CNTs and SiO&lt;sub&gt;2&lt;/sub&gt; for thermostability and mechanical properties of PF microcapsules: used for self-healing of closed wall cracks in goaf

Air leakage of closed wall in coal mine goaf would cause spontaneous combustion of remained coal. Most of measures to repair cracks are carried out after cracks are penetrated, which is not conducive to early prevention of spontaneous combustion. Repairing damage at the initial stage of cracking makes prevention effect to the best. Phenol-formaldehyde resin (PF) microcapsules embedded in closed wall to achieve self-healing of initial cracks, but the actual repair effect is often less than expected. PF microcapsules (PFM) of carbon nanotubes (CNTs) and silicon dioxide (SiO2) decorated shell for self-healing of closed wall cracks were prepared by in-situ polymerization. The effects of nanomaterials on morphology, chemical constitution, thermal performance and mechanical properties of PF microcapsules were characterized by scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and nanoindentation test. The test results indicated that nanomaterials were successfully introduced into the shell of PF microcapsules. The CNTs-SiO2@PF microcapsules were uniformly dispersed, the thermal decomposition was delayed, and the residual carbon was significantly increased, and the brittleness of PF microcapsules was significantly enhanced. The 0.2CNTs-SiO2@PF microcapsules (0.2CNTs-SiO2@PFM) had a uniform and full particle size, the initial decomposition temperature was 267.6 ℃, the residual mass was 41.3%, the maximum load on the capsule wall reached 94.79 mN, and the load dropped sharply after the capsule wall rupture. Finally, the self-healing mechanism of closed wall doped with microcapsules was discussed. The exploration of modified phenolic microcapsules provides a new idea for the repair of closed wall in goaf.

Effect of alternative silicon sources on alkali-activated carbon steel slag binder and silicon sources substitution mechanism

The high cost and carbon footprint of conventional alkali activator (sodium silicate) limit the wide-scale adaptation of alkali-activated materials. During the production of sodium silicate(SS), carbonate and silicate need to be calcined at 1400 °C, which is not environmentally friendly. In order to improve the sustainability of the activator, 10% SS was reduced in this paper. The effect alternative silicon sources (ASS) on the mechanical properties of alkali-activated carbon steel slag (CSS) prepared at room temperature were studied when the modulus is 0.5 and 1.0, and the mechanism of silicon source substitution was discussed by means of microscopic characterization. The substitution amount of ASS was 10% of the total CSS amount. ASS included waste glass powder (WGP), rice husk ash (RHA), diatomaceous earth (DE), diatomaceous earth analytical reagent (DEAR), and silica fume (SF). Microscopic characterization methods included X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetry and differential thermogravimetry (TG-DTG), and scanning electron microscope-energy dispersive spectrometer (SEM-EDS). The results show that the effect of ASS depended on the structure of SiQn, and is affected by the initial modulus of the activator. The compressive strengths of the low modulus samples are lower than that of the high modulus samples, while the effect of silicon source substitution is the opposite. However, the effect of SF is less affected by the initial modulus, and the 90d compressive strength of low modulus and high modulus differed by only 8%. 10% SF substitution can save at least 48.28% of industrial SS. SF is an economic and effective ASS, which can provide a better ecological choice for the production of alkali-activated CSS cementitious materials.

Solution-catalyzed carbothermal reduction of argo-waste SiO2 enables low-temperature and fast synthesis of Si(Ⅱ)-C anode

Divalent silicon composite materials are becoming increasingly important in the anode industry of lithium-ion battery. However, the preparation of silicon(Ⅱ) composite materials based on traditional carbothermal reduction and comproportionation faces high operation temperature, high energy consumption, and relatively slow reaction rate due to strong Si-O covalent bonds and solid-state reaction process. Here, we report an efficient carbothermal reduction strategy to achieve low-temperature synthesis of carbon-based silicon(Ⅱ) composite from argo-waste SiO2 by introducing molten alloys as solution-catalytic reaction media. During the reaction process, the selected Sn-based molten alloys simultaneously extract SiO2 and highly active carbon from straws, thus facilitating the dissociation of Si-O bonds and further catalyzing the carbothermal reduction. Importantly, compared with traditional solid phase reaction, the Sn-based solution-catalytic environment can greatly accelerate the reaction rate. Without using highly reactive metal such as Al and Mg, low oxygen-potential Sn-based molten alloy catalyst can be easily separated from the product, recycled and regenerated, thus significantly simplifying the preparation process. Benefitting from the structure merits of biomass, the resulting carbon silicon(Ⅱ) composite as a LIB anode exhibits high reversible capacity, good rate capability and excellent cycling stability.

Properties of SiCN Films Relevant to Dental Implant Applications.

The application of surface coatings is a popular technique to improve the performance of materials used for medical and dental implants. Ternary silicon carbon nitride (SiCN), obtained by introducing nitrogen into SiC, has attracted significant interest due to its potential advantages. This study investigated the properties of SiCN films deposited via PECVD for dental implant coatings. Chemical composition, optical, and tribological properties were analyzed by adjusting the gas flow rates of NH3, CH4, and SiH4. The results indicated that an increase in the NH3 flow rate led to higher deposition rates, scaling from 5.7 nm/min at an NH3 flow rate of 2 sccm to 7 nm/min at an NH3 flow rate of 8 sccm. Concurrently, the formation of N-Si bonds was observed. The films with a higher nitrogen content exhibited lower refractive indices, diminishing from 2.5 to 2.3 as the NH3 flow rate increased from 2 sccm to 8 sccm. The contact angle of SiCN films had minimal differences, while the corrosion rate was dependent on the pH of the environment. These findings contribute to a better understanding of the properties and potential applications of SiCN films for use in dental implants.

Synthesis of Si/C Composites by Silicon Waste Recycling and Carbon Coating for High-Capacity Lithium-Ion Storage.

It is of great significance to recycle the silicon (Si) kerf slurry waste from the photovoltaic (PV) industry. Si holds great promise as the anode material for Li-ion batteries (LIBs) due to its high theoretical capacity. However, the large volume expansion of Si during the electrochemical processes always leads to electrode collapse and a rapid decline in electrochemical performance. Herein, an effective carbon coating strategy is utilized to construct a precise Si@CPPy composite using cutting-waste silicon and polypyrrole (PPy). By optimizing the mass ratio of Si and carbon, the Si@CPPy composite can exhibit a high specific capacity and superior rate capability (1436 mAh g-1 at 0.1 A g-1 and 607 mAh g-1 at 1.0 A g-1). Moreover, the Si@CPPy composite also shows better cycling stability than the pristine prescreen silicon (PS-Si), as the carbon coating can effectively alleviate the volume expansion of Si during the lithiation/delithiation process. This work showcases a high-value utilization of PV silicon scraps, which helps to reduce resource waste and develop green energy storage.