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The further commercialization of layer-structured Ni-rich LiNi 0.83 Co 0.11 Mn 0.06 O 2 (NCM83) cathode for high-energy lithium-ion batteries (LIBs) has been challenged by severe capacity decay and thermal instability owing to the microcracks and harmful phase transitions. Herein, Ti 4+ -doped NCM83 cathode materials are rationally designed via a simple and low-cost in-situ modification method to improve the crystal structure and electrode-electrolyte interface stability by inhibiting irreversible polarizations and harmful phase transitions of the NCM83 cathode materials due to Ti 4+ -doped forms stronger metal-O bonds and a stable bulk structural. In addition, the optimal doping amount of the composite cathode material is also determined through the results of physical characterization and electrochemical performance testing. The optimized Ti 4+ -doped NCM83 cathode material presents wider Li + ions diffusion channels (c = 14.1687 Å), lower Li + /Ni 2+ mixing degree (2.68 %), and compact bulk structure. The cell assembled with the optimized Ti 4+ -doped NCM83 cathode material exhibits remarkable capacity retention ratio of 95.4 % after 100cycles at 2.0C and room temperature, and outstanding reversible discharge specific capacity of 148.2 mAh g -1 at 5.0C. Even under elevated temperature of 60 °C, it delivers excellent capacity retention ratio of 92.2 % after 100cycles at 2.0C, which is significantly superior to the 47.9 % of the unmodified cathode material. Thus, the in-situ Ti 4+ -doped strategy presents superior advantages in enhancing the structural stability of Ni-rich cathode materials for LIBs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

From the swollen LDH, bulky [Mo 3 S 13 ] 2- anions are facilely introduced into the LDH interlayers to assemble the Mo 3 S 13 -LDH composite, which exhibits excellent iodine capture performance and good irradiation resistance. The positive-charged LDH layers may disperse the [Mo 3 S 13 ] 2- uniformly within the interlayers, providing abundant adsorption sites for effectively trapping iodine. The Mo-S bond serving as a soft Lewis base has strong affinity to I 2 with soft Lewis acidic characteristic, which is conducive to improvement of iodine capture via physical sorption. Besides, chemisorption has a significant contribution to the iodine adsorption. The S 2 2- /S 2- in [Mo 3 S 13 ] 2- can reduce the I 2 to [I 3 ] - ions, which are facilely fixed within the LDH gallery in virtue of electrostatic attraction. Meanwhile, the S 2 2- /S 2- themselves are oxidized to S 8 and SO 4 2- , while Mo 4+ is oxidized (by O 2 in air) to Mo 6+ , which combines with SO 4 2- forming amorphous Mo(SO 4 ) 3 . With the collective interactions of chemical and physical adsorption, the Mo 3 S 13 -LDH demonstrates an extremely large iodine adsorption capacity of 1580 mg/g. Under γ radiation, the structure of Mo 3 S 13 -LDH well maintains and iodine adsorption capability does not deteriorate, indicating the good irradiation resistance. This work provides an important reference to tailor cost-effective sorbents for trapping iodine from radioactive nuclear wastes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

InCl 3 @Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 -F (InCl 3 @LATP-F) solid electrolyte powders are designed and fabricated by coating a uniform InCl 3 layer on the surface of F - -doped Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 (LATP-F) solid powders via a feasible wet-chemical technique. The assembled Li/InCl 3 @LATP-F/Li cell can undergo longer cycles of 2500 h at 0.4 mA cm -2 without obvious increases in the overvoltage compared to 1837 h for the Li/LATP-F/Li cell, and the interfacial resistance demonstrates a sharp decrease from 3428 to 436 Ω for the Li/InCl 3 @LATP-F/Li cell during the first 500 h. Importantly, the assembled LiCoO 2 /InCl 3 @LATP-F/Li cell delivers a high discharge specific capacity of 126.4 mAh g -1 with a 95.42% capacity retention ratio after 100 cycles at 0.5 C, and the value easily returns to 112.9 mAh g -1 when the current density is abruptly set back to 0.1 C after different rate cycles. These improved results can be mainly attributed to the fact that the InCl 3 layer with a lithiophilic nature can react with lithium metal to form a Li-In alloy, which can guarantee homogeneous lithium ion flux to avoid the accumulation of ions/electrons across the interface and suppress the growth of lithium dendrites. Moreover, the InCl 3 layer can prevent direct contact of the LATP-F solid electrolyte and lithium metal to effectively alleviate the reduction reaction of Ti 4+ and preserve the structural stability of the composite electrolyte. Therefore, this work may provide an effective strategy to engineer and regulate the interfacial stability between LATP solid electrolytes and lithium metal anodes for LATP-type solid-state lithium batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

A facile in-situ preparation strategy is proposed to anchor amorphous SnO 2 nanoparticles into the porous N-doped carbon (NC) matrix to fabricate amorphous composite powders (am-SnO 2 @p-NC), which feature the hierarchically interconnected and well interlaced porous configurations by employing polyvinylpyrrolidone as the soft template. The morphology regulation of the porous structure is precisely realized by adjusting the content of the template and the relationship between structural evolution and electrochemical performance of composite powders is accurately described to explore the optimal template dosage. The results indicate that the am-SnO 2 @p-NC-50 % composite electrode can deliver the improved lithium storage capacity and cycling performance when the content of the template is controlled at 0.500 g, in which the initial discharge specific capacity is about 1557.6 mAh/g and the reversible value retains at 841.5 mAh/g after 100 cycles at 100 mA/g. Meanwhile, the discharge specific capacity of 869.8 mAh/g is exhibited for the am-SnO 2 @p-NC-50 % composite electrode after 60 cycles when the current density is recovered from 2000 to 100 mA/g. Moreover, the Li + ions diffusion coefficient up to about 5.5 × 10 -12 cm 2 /s is calculated from galvanostatic intermittent titration technique tests, which can be partly ascribed to the conductive NC substrate that provides the high electronic conductivity, and partly to the highly porous structure that shortens Li + ions transfer pathways and guarantees the fast reaction kinetics. Therefore, the hierarchically porous engineering of carbon networks to confine amorphous transition metal oxide nanoparticles is of great significance in the development of high-performance anode materials for lithium-ion batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The layered Nb 5+ -doped LiNi 0.83 Co 0.11 Mn 0.06 O 2 (NCM) oxide cathode materials are successfully synthesized through introducing Nb 2 O 5 into the precursor Ni 0.83 Co 0.11 Mn 0.06 (OH) 2 during the lithiation process. The results refined by GSAS software present that the Nb 5+ -doped samples possess the perfect crystal structure with broader Li + diffusion pathways. Moreover, the morphology characterized by scanning electron microscope displays the compact secondary particles packed by smaller primary particles under the effect of Nb 5+ . The excellent electrochemical properties are also acquired from the Nb 5+ -doped samples, in which the optimal rate performance and cycling stability are performed for NCM-1.0 when up to 1.0 mol % of Nb 2 O 5 (based on the precursor) is added. Benefited from the introduction of Nb 5+ , the cell assembled with the NCM-1.0 electrode retains higher capacity retention of 86.6 % at 1.0 C and 25 °C, and 71.7 % at 1.0 C and 60 °C after 200cycles. Moreover, it also delivers higher discharge specific capacity of 154.6 mAh g -1 at 5.0 C. Therefore, the Nb 5+ -doping strategy may open an effective route for optimizing nickel-rich oxide cathode materials, which is worth popularizing for the enhancement of the electrochemical performance of nickel-rich cathodes for lithium-ion batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The SnSb and TiO 2 nanoparticles uniformly embedded into continuous and conductive carbon nanofibers (CNFs) are successfully fabricated through facile electrospinning combined with calcination treatments. The characterization results of the targeted composite nanofibers (Sb-SnSb/TiO 2 @CNFs-2) confirm that the presence of TiO 2 is of significant importance to construct the elaborately designed and intact fiber structure, in which the optimal dosage of the TiO 2 precursor is precisely controlled at 2 mmol. Moreover, high theoretical specific capacity of SnSb, available inhibitory effect of TiO 2 , and great electronic conductivity of CNFs are cooperatively integrated into the Sb-SnSb/TiO 2 @CNFs-2 composite nanofibers, guaranteeing the enhanced lithium storage capacity and cycling performance when being employed as the anode electrodes. Specifically, the Sb-SnSb/TiO 2 @CNFs-2 electrode can not only deliver initial discharge specific capacity of 1146.6 mAh/g at 100 mA/g and reversible discharge specific capacity of 580.4 mAh/g after 100 cycles, but also retain discharge specific capacity of 561.3 mAh/g after rate cycles along with recovering the current density to 100 mA/g. Importantly, the Sb-SnSb/TiO 2 @CNFs-2 electrode is also endowed with prominent advantages in the pseudocapacitive contribution of 66.89 % at 0.8 mV/s. Those investigations and findings of the Sb-SnSb/TiO 2 @CNFs-2 composite electrodes with facile fabrication process and excellent electrochemical performance can contribute to the practical application of the alloy anodes in the field of the energy storage., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The structural stability and reaction kinetics of anodes are essential factors for high-performance battery systems. Herein, the molybdenum sulfide selenide (MoSSe) nanosheets anchored on carbon tubes (MoSSe@CTs) are synthesized by a facile hydrothermal method combining with further selenization/calcination treatment. The unique tubular carbon skeletons expose abundant active sites for the well-dispersed growth of MoS 2 ultrathin nanosheets on both sides of the tubular carbon skeleton. In addition, the further selenization treatment can expand the interlayer spacing of molybdenum sulfide (MoS 2 ) nanosheets and facilitate the fast sodium/potassium-ion transition and storage. When used in sodium-ion batteries (SIBs), MoSSe@CTs electrode delivers a specific capacity of 486 mAh g -1 at 1 A g -1 and retains a stable reversible capacity of 465 mAh g -1 after 1000 cycles, indicating its good cycling stability. For potassium-ion batteries (KIBs), the MoSSe@CTs composite shows a capacity of 352 mA hg -1 at 1 A g -1 and a good cycling stability (maintains at 272 mA hg -1 after 1000 cycles). This work shows informative guiding significance for exploring advanced electrode materials of sodium/potassium-ion batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

WO 3 as tungsten dopant is introduced into lithium nickel cobalt manganese (LiNi 0.83 Co 0.11 Mn 0.06 O 2 , NCM) layered oxide powders to synthesize W 6+ -doped NCM cathode materials during the lithiation process of the hydroxide precursor. Introducing W 6+ into the lattice can lead to the diversities of the crystal structure, surface morphology, and electrochemical performance. The crystal structure confirmed by X-ray diffraction indicates that the W 6+ -doped oxide powders present a typical R-3m layered structure with larger interplanar distance and cell volume. Also, scanning electron microscope images reveal that the primary particles shrink forming a tighter surface under the effect of W 6+ , while the specific changes gradually aggravate with increase in the content of W 6+ added. The excellent electrochemical stability of W 6+ -doped samples is observed, as the stable host structure is reinforced by the strong W-O bond. The stable structure does not only inhibit the anisotropic volume change caused by repetitive H2 ⇔ H3 phase transitions, but also sustains the integrated structure to impede the formation of microcracks and the appearance of more side reactions. This research provides an effective route on investigating the potential association between electrochemical performance and structure change for W 6+ -doped strategy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Here in this article, a halloysite nanotube/reduced graphene oxide/cobalt nickel composite (HNT/rGO/CoNi) was synthesized by co-precipitation and subsequent calcination processes. The microstructure, morphology, and chemical composition of the as-synthesized samples were characterized by X-ray diffractometer, Raman spectra, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The electromagnetic absorption performances of the composites/paraffin wax hybrids were tested in the frequency range 2-18 GHz. It was found that the synergistic attenuation of electricity and magnetism, as well as the fairly good impedance matching properties together have led to the impressive electromagnetic absorption performance of the optimized product. The maximum reflection loss can reach - 69.77 dB with the thickness of 2.38 mm at 14.72 GHz, and an effective absorption bandwidth of about 7.12 GHz (10.88 GHz-18.00 GHz) can be achieved in the HNT/rGO/CoNi (30) composite. The excellent microwave absorption performance was estimated to originate from the combination of multiple electromagnetic loss mechanisms, including interfacial polarization between graphene and magnetic nanoparticles, dipole orientation polarization caused by the defects of graphene, the natural ferromagnetic resonance, and eddy current of the magnetic nanoparticles. Furthermore, the halloysite plays the roles of improving dispersion of the magnetic nanoparticles as well as adjusting the complex permittivity of the composite. This work provides a new strategy for the design and fabrication of high performance microwave absorbing materials with natural and readily available components., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Aqueous rechargeable Zn-ion batteries (ARZIBs) have been attracting a great deal of attention due to their immense potential in large-scale power grid applications. It is of great significance to explore cathode material with novel designed structure and first-class performances for ARZIBs. Herein, we successfully construct a double-sandwich-like structure, MOF-derived carbon/manganese silicate/reduced graphene oxide/manganese silicate/MOF-derived carbon (denoted as rGO/MnSi/MOF-C), as the cathode material for ARZIBs. Among the double-sandwich-like structure, manganese silicate (Mn 2 SiO 4 , denoted as MnSi) is in the middle of internal reduced graphene oxide (rGO) and external MOF-8 derived carbon (MOF-C). This integrated rGO/MnSi/MOF-C with double-sandwich-like structure can not only avert the sluggish electronic conduction progress caused by the conventional three-phase mixture system of rGO, MnSi and MOF-C, but also display promising Zn 2+ storing capability. As expected, in mild aqueous 2 M (mol L -1 ) ZnSO 4  + 0.2 M MnSO 4 electrolyte, the initial discharge capacity of rGO/MnSi/MOF-C cathode reaches to 246 mAh·g -1 , and the peak discharge capacity reaches to 462 mAh·g -1 at 0.1 A·g -1 . This work not only involves the novel MnSi-based cathode for ARZIBs, but also first demonstrates our assumption of constructing the double-sandwich-like structure to improve Zn 2+ storage. Moreover, the concept "double-sandwich-like structure" provides an idea for synthesizing the integrated carbon/transition metal silicates (TMSs)/carbon structure to boost the electrochemical properties of TMSs for energy-storing devices., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Hypothesis: High and medium internal phase Pickering emulsions stabilized with cellulose nanocrystals (CNCs) exhibited very different performance compared to their peers stabilized with a surfactant. In this paper, we ascribed the difference to the formation of hydrogen bonding and van der Waals interactions between the CNC nanoparticles on adjacent oil droplets., Experiments: Rheological properties of CNC-stabilized oil-in-water medium internal phase emulsions (MIPEs, oil content = 65% v/v) and high internal phase emulsions (HIPEs, oil content = 80% v/v) were comprehensively characterized using both oscillatory and rotational tests., Findings: It was found that in the MIPEs, the van der Waals and hydrogen bonding interactions dominate the emulsion properties, whereas the compact structure of oil droplets plays a more important role in the HIPEs. CNC concentration in the aqueous phase also affects the emulsion properties, especially for the HIPEs, and the results can be correlated to the stabilization mechanisms we previously reported. The information from these tests provides a much-needed guidance for the practical application of CNC-stabilized emulsions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Li 3 PO 4 coating Li 0.98 Mg 0.01 Ni 0.83 Co 0.11 Mn 0.06 O 2 (NCM83-MP) composite powders are successfully synthesized by first doping Mg 2+ into LiNi 0.83 Co 0.11 Mn 0.06 O 2 by co-calcination processes and followed by H 3 PO 4 modifying the obtained Li 0.98 Mg 0.01 Ni 0.83 Co 0.11 Mn 0.06 O 2 composite powders by sol-gel methods. Related physicochemical characterization results demonstrate that Mg 2+ doping can significantly enlarge the lattice space along the c-axis to 14.1431 Å and lower the Li/Ni mixing degree to 1.58 %, and H 3 PO 4 modifying can effectively reduce the residual lithium content and generate a homogeneous Li 3 PO 4 covering with a thickness of about 11.7 nm on the surface of the composite particles. Furthermore, the battery performance tests indicate that the coin cells assembled with NCM83-MP can exhibit excellent cycling performance, in which the distinguished discharge specific capacity of 157.4 mAh g -1 at 2.0 C at 25 °C after 200 cycles and 154.6 mAh g -1 at 2.0 C at 60 °C after 100cycles are amazingly retained, respectively. Additionally, the electrode can present a smaller gap of redox peaks of 0.10 V and a lower resistance value of 193.8 Ω compared to the ones of 0.49 V and 451.8 Ω of NCM83-0 after cycles. Those enhanced electrochemical properties are mainly ascribed to the synergetic effect of Mg 2+ doping and H 3 PO 4 modifying, which can not only stabilize the lattice structure but also provide fast transfer channels to facilitate Li ions migrating. Therefore, the proposed strategy may excavate new ideas to the further investigation of high-performance Ni-rich cathode materials for lithium ion battery., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The nitrogen-doped carbon (NC) coating encapsulating heterostructural Sn/SnO 2 microcube powders (Sn/SnO 2 @NC) are successfully fabricated through hydrothermal, polymerization of hydrogel, and carbonization processes, in which the SnO precursor powders exhibit regular microcube structure and uniform size distribution in the presence of optimized N 2 H 4 ·H 2 O (3.0 mL of 1.0 mol/L). Interestingly, the precursor powders are easily subjected to a disproportionated reaction to yield the desirable heterostructural Sn/SnO 2 @NC microcube powders after being calcined at 600 °C in N 2 atmosphere in the presence of home-made hydrogel. The coin cells assembled with the Sn/SnO 2 @NC electrode present a high initial discharge specific capacity (1058 mAh g -1 at 100 mA g -1 ), improved rate capability (an excellent D Li+ value of 2.82 × 10 -15 cm 2 s -1 ) and enhanced cycling stability (a reversible discharge specific capacity of 486.5 mAh g -1 after 100 cycles at 100 mA g -1 ). The enhanced electrochemical performance can be partly ascribed to the heterostructural microcube that can accelerate the transfer rate of lithium ions by shortening the transmission paths, and be partly to the NC coating that can accommodate the volume effect and contribute to partial lithium storage capacity. Therefore, the strategy may be able to extend the fabrication of Sn/SnO 2 heterostructural microcube powders and further application as promising anode materials in lithium ion batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

To optimize the electrochemical performance of Ni-rich cathode materials, the 0.005 mol of Mg 2+ and 0.005 mol of Ti 4+ co-doping LiNi 0.83 Co 0.11 Mn 0.06 O 2 composite powders, labeled as NCM-11, are successfully prepared by being calcinated at 750 °C for 15 h following by an appropriate post-treatment, which are confirmed by XRD, EDS and XPS. The results suggest that NCM-11 presents a well-ordered layered structure with a low Li + /Ni 2+ mixing degree of 1.46% and Mg 2+ and Ti 4+ ions are uniformly distributed across the lattice. The cell assembled with NCM-11 can deliver an initial discharge specific capacity of 194.2 mAh g -1 and retain a discharge specific capacity of 163.0 mAh g -1 after 100cycles at 2.0C at 25 °C. Furthermore, it still maintains a discharge specific capacity of 166.7 mAh g -1 after 100cycles at 2.0C at 60 °C. More importantly, it also exhibits a higher discharge specific capacity of about 150.7 mAh g -1 even at 5.0C. Those superior electrochemical performance can be mainly ascribed to the synergistic effect of Mg 2+ and Ti 4+ co-doping, in which Mg 2+ ions can occupy the Li + layer to act as pillar ions and Ti 4+ ions can occupy the transition metal ions layer to enlarge the interplane spacing. Thus, the heterovalent cations co-doping strategy can be considered as a simple and practical method to improve the electrochemical performance of Ni-rich layered cathode materials for lithium-ion batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

One promising way to improve the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs), which have attracted great interest due to their low cost, is modifying the working electrode. In this work, Tm and Yb doped as well as undoped In2O3 inverse opals (IOs) were synthesized by the sol-gel method. DSSCs based on In2O3, In2O3:Tm and In2O3:Yb IOs as photoanodes were fabricated and studied. It is observed that the device performance including open-circuit voltage (V(oc)) and short-circuit current (J(sc)) increased largely with the increasing pore size of the IOs and the introduction of Tm and Yb elements in the In2O3 lattices. The PCE of the DSSC was increased from 0.33% to 0.96% when the ln2O3 IOs photoanode was substituted by ln2O3:Yb IOs. The electrochemical impedance spectroscopy (EIS) measurements indicate that the modification of band gap in the Tm and Yb doped In2O3 IOs is significant for the improved performance, which can effectively suppress the charge transfer recombination and improve the electron lifetime., (Copyright © 2015 Elsevier Inc. All rights reserved.)

In this work, rare earth (RE) ion RE(3+) (RE(3+)=Dy(3+), Ho(3+) and Er(3+)) doped and undoped In2O3 nanotubes are synthesized by the electrospinning method and the band gap of In2O3 is systemically controlled, depending on the order of doped elements. Dye-sensitized solar cells (DSSCs) based on In2O3:RE(3+) nanotubes are also fabricated, and significantly improved performance of In2O3-DSSC is observed due to the modulation of the band gap, larger recombination charge transfer resistance and longer electron lifetime., (Copyright © 2014 Elsevier Inc. All rights reserved.)

This paper describes the surface modification of micrometer-sized magnetic carbonyl iron particles (CI) with zirconia from zirconium(IV) butoxide using a sol-gel method. Zirconia shells with various thicknesses and different grain sizes and shapes are coated on the surface of CI particles by changing the reaction conditions, such as the amounts of zirconia sol, nitric acid, and CI particles. A silica adhesive layer made from 3-aminopropyl trimethoxysilane (APTMS) can be introduced first onto the surface of CI particles in order to adjust both the size and the shape of zirconia crystals, and thus the roughness of the coating. The microanalyses on these coated particles are studied by field-emission scanning electron microscopy (FE-SEM) and X-ray-diffraction (XRD). Accelerated acid corrosion and air oxidation tests indicate that the coating process dramatically improved oxidation and acid corrosion resistances, which are critical issues in various applications of CI magnetic particles., (Copyright 2009. Published by Elsevier Inc.)

Two different groups of comb-like copolymer dispersants with side chain lengths ranging from 8 to 48 were synthesized and characterized: one group with the carboxylic content per mole molecule constant and the other group with the carboxylic contents per gram polymer constant. The effects of side chain length on comb-like copolymers on adsorption, dispersion, rheological behavior, and zeta potential for cement suspensions were investigated systematically to elucidate the governing dispersing mechanism. The adsorption of comb-like copolymer on the cement surfaces, controlled by COO(-) content in copolymer backbones, side chain length, and also polymer conformation in solution, governs the dispersion and rheological behavior of the cementitious system. The dispersion effect increases with the adsorbed amount; especially the adsorbed side chain density increases. But the dispersion power of comb-like copolymers varies depending on the side chain length in comb-like copolymer. The long side chain polymer has higher dispersion power than the shorter ones due to the stronger steric hindrance effect of the former; for the short side chain polymer with high ionic content, the electrostatic repulsion and steric hindrance together should be responsible for its dispersion effect. Such information also suggests that their exists the geometrical balance between the main chain and the side chains in comb-like copolymer dispersants which should be very useful in designing optimum molecular structures of high efficient dispersants.