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Lithium-ion battery (LIB) is the dominant energy storage device for the application on electric vehicles and portable electronic devices. Up to now, the enhancement of LIBs’ energy density mainly depends on the improvement of anode’s capacity. Due to the obstacle of large volume effect and low rate performance, the use of intrinsic high-capacity anodes, such as silicon, is still in the laboratory stage. Combining battery and capacitor to improve the electrochemical performance of the commercial carbon anode is an alternative and effective strategy in practical application. In this paper, a high nitrogen (N) content (8.2%) carbon is obtained by pyrolyzing the melamine formaldehyde (MF) foam resin at low temperature (600 °C). It delivers a stable specific capacity of around 600 mAh g−1 at 0.1C. No significant capacity degradation appears after 200 cycles, and the coulombic efficiency maintained over 99.5%. Even at 1.2 C, a specific capacity of 350 mAh g−1 is delivered and so a Li-ions diffusion coefficient of 1.8×10–13 cm2s-1. The reason of the superior electrochemical performance of the high N-doped carbon anode is the synergistic effect of battery and capacitor. The calculated pseudocapacitance proportion is from 32 to 61% at scan rate from 0.1 to 1mV s−1.

In the mixed matrix membrane (MMM), the interface between the filler and the polymer matrix will directly affect the gas separation performance of the membranes. Reasonable interfacial design in MMMs is thus important and necessary. In this work, metal-organic coordination interaction is used to construct the interface in metal-organic framework (MOF) nanosheet-based polyimide MMMs where ultrathin Co-benzenedicarboxylate MOF nanosheets (CBMNs) with a thickness less than 5 nm and a lateral size more than 5 μm are synthesized as fillers and a carboxyl-functionalized polyimide (6FDA-durene-DABA) is used as a polymer matrix. Because of the high aspect ratio (>1000) of CBMNs, abundant metal-organic coordination bonds are formed between Co2+ in CBMNs and the -COOH group in 6FDA-durene-DABA. As a result, the 6FDA-durene-DABA/CBMN MMMs exhibit improved separation performance for the CO2/CH4 and H2/CH4 gas pairs with H2/CH4 and CO2/CH4 selectivities up to 42.0 ± 4.0 and 33.6 ± 3.0, respectively. The enhanced interfacial interaction leads to the comprehensive separation performance of CO2/CH4 and H2/CH4 gas pairs approaching or surpassing the 2008 Robeson upper bound. In addition, the CO2 plasticization pressure of the MMMs is significantly enhanced up to ∼20 bar, which is 2 times that of the pure 6FDA-durene-DABA membrane. When separating a mixed gas of CO2/CH4, the selectivity of CO2/CH4 remains stable at around 23 and the CO2 permeability keeps around 400 barrer during the long-term test.

We have synthesized and characterized a new family of nematic all-aromatic polyesteramide thermosets based on 6-hydroxy-2-naphthoic acid (HNA), terephthalic acid (TA), and 4-acetamidophenol (AAP). In order to incorporate a high concentration of the amide-based monomer (AAP), the melt transition ( T K-N) and melt viscosity had to be lowered in order to maintain melt processable intermediates. Precursor thermoplastic reactive oligomers, end-capped with phenylethynyl functionalities, were prepared using standard melt condensation techniques with a target M n of 1000–9000 g mol−1. The reactive oligomers with 20–30 mol% AAP could easily be processed into films, and the films exhibit good tensile properties in terms of tensile strength (70–80 MPa) and elongation at break (7–10%). A glass transition of 191°C could be obtained when a 1000 g mol−1 oligomer (HNA/TA/AAP(20)–1 K) was thermally cross-linked. When the AAP concentration reaches 35 mol%, the rigidity of the backbone and the hydrogen bonding interactions are enhanced, which make HNA/TA/AAP(35) polymers difficult to process.

Metal organic frameworks (MOFs) are ideal fillers for preparing mixed matrix membranes (MMMs) because of their molecular sieving property. However, MOF nanoparticles are not easy to be dispersed, which limits their application in MMMs with high MOFs loading. In this study, highly dispersed ZIF-8 nanoparticles with diameter of around 50 nm were prepared by coating isophthalic dihydrazide (IPD) molecular layer onto their surfaces via coordination interaction (abbre. IPD@ZIF-8). Benefiting from the highly stable and highly dispersed IPD@ZIF-8 solution, MMMs with high nanoparticles loading content and excellent uniformity are achieved. The modification of IPD on the surface of ZIF-8 nanoparticles greatly enhances the interfacial affinity between ZIF-8 as filler and 6FDA-Durene polyimide (PI) as polymer matrix under the interaction of strong hydrogen bond between them. Gas permeation results reveal that the H2 permeability of IPD@ZIF-8 mixed PI (PI/IPD@ZIF-8) MMM with 45 wt% loading content is up to 8000 Barrer and the corresponding ideal selectivities of H2/CH4 and H2/N2 gas pairs are 15.1 and 13.0, which increase by 46.6% and 32.7%, respectively, comparing to those of ZIF-8 mixed PI (PI/ZIF-8) MMMs. The comprehensive separation performance of PI/IPD@ZIF-8 MMMs surpasses the 2008 Robeson’s upper bounds. The surface modification of IPD enhances the CO2 plasticization resistance property of PI/IPD@ZIF-8 MMMs from 21 bar to 30 bar. This study provides a facile and easy-operated strategy for the surface modification of MOF nanoparticles, and opens up a new way for the preparation of MMMs with high filler loading and good quality.

In nanocomposite electrodes, besides the synergistic effect that takes advantage of the merits of each component, phase interfaces between the components would contribute significantly to the overall electrochemical properties. However, the knowledge of such effects is far from being well developed up to now. The present work aims at a mechanistic understanding of the phase interface effect in C@TiO2core-shell nanocomposite anode which is both scientifically and industrially important. Firstly, amorphous C, anatase TiO2and C@anatse-TiO2electrodes are compared. The C@anatase-TiO2shows an obvious higher specific capacity (316.5 mAh g-1at a current density of 37 mA g-1after 100 cycles) and Li-ion diffusion coefficient (4.0 × 10-14cm2s-1) than the amorphous C (178 mAh g-1and 2.9 × 10-15cm2s-1) and anatase TiO2(120 mAh g-1and 1.6 × 10-15cm2s-1) owing to the C/TiO2phase interface effect. Then, C@anatase/rutile-TiO2is obtained by a heat treatment of the C@anatase-TiO2. Due to an anatase-to-rutile phase transformation and diffusion of C along the anatase/rutile phase interface, additional abundant C/TiO2phase interfaces are created. This endows the C@anatase/rutile-TiO2with further boosted specific capacity (409.4 mAh g-1at 37 mA g-1after 100 cycles) and Li-ion diffusion coefficient (3.2 × 10-13cm2s-1), and excellent rate capability (368.6 mAh g-1at 444 mA g-1). These greatly enhanced electrochemical properties explicitly reveal phase interface engineering as a feasible way to boost the electrochemical performance of nanocomposite anodes for Li-ion batteries.

Molecular sieve materials (MSMs) are regarded as ideal fillers for the fabrication of mixed matrix membranes (MMMs). However, the preparation of MSMs-based MMMs usually involves physical mixing of insoluble filler and polymer matrix, which inevitably leads to filler agglomeration and two-phase incompatibility especially for high filler loading. Herein, we report a new strategy to construct MMMs through generating polymer molecular sieve (PMS) fillers in-situ in a thermally stable polymer matrix by post heating treatment. The in-situ generated PMS-based MMMs (i-PMS MMMs) possess greatly improved interfacial compatibility between matrix and filler and the effective loading content of PMS filler can reach as high as 70 wt%. The molecular sieving property of PMS endows the i-PMS MMMs with high gas selectivity of 183.0 for H2/CH4 and 128.9 for H2/N2, approaching or exceeding the state-of-the-art 2015 upper bound.

Polyimide has been widely investigated as a potential material for gas separation. The post-crosslinking of polyimide could increase gas selectivity and membrane stability due to increase of chain-packing density and chain stiffness. However, common crosslinking strategies tend to destroy the chemical structure of polyimide. In this work, a strong hydrogen bond among polymer chains of 6FDA-durene polyimide (Du-PI) membranes is designed by introducing isophthalic dihydrazide (IPD) molecules as cross-linker. The formation of hydrogen bond between Du-PI and IPD strengthens the polymer interchain interaction and regulates interchain spacing but without breaking the chemical structure of Du-PI. The resulting IPD/Du-PI membranes exhibit largely enhanced mechanical strength and anti-plasticization property in comparison with pristine Du-PI membranes. In addition, due to the increased packing density of polymer chains, the membranes show obviously increased gas perm-selectivity by 296%, 505%, 125%, 66%, and 171% for H2/N2, H2/CH4, H2/CO2, O2/N2, and CO2/CH4 gas pair in the case of 20% IPD/Du-PI membrane. The use of IPD as cross-linker has demonstrated herein to be a facile and effective strategy to strengthen the inter-polymer chain interaction and simultaneously improve membrane stability in a mild way.

This tutorial review focuses on aqueous slurries of dispersed engineered nanoparticles (ENPs) used in chemical mechanical planarization (CMP) for polishing wafers during manufacturing of semiconductors. A research consortium was assembled to procure and conduct physical, chemical, and in vitro toxicity characterization of four ENPs used in CMP. Based on input from experts in semiconductor manufacturing, slurries containing fumed silica (f-SiO2), colloidal silica (c-SiO2), ceria (CeO2), and alumina (Al2O3) were selected and subsequently obtained from a commercial CMP vendor to represent realistic ENPs in simplified CMP fluids absent of proprietary stabilizers, oxidants, or other chemical additives that are known to be toxic. ENPs were stable in suspension for months, had highly positive or negative zeta potentials at their slurry working pH, and had mean diameters measured by dynamic light scattering (DLS) of 46 ± 1 nm for c-SiO2, 148 ± 5 nm for f-SiO2, 132 ± 1 nm for CeO2, and 129 ± 2 nm for Al2O3, all of which were larger than the sub 100 nm diameter primary particle sizes measured by electron microscopy. The concentration of ENPs in all four slurries that caused 50% inhibition (IC-50) was greater than 1 mg mL−1 based on in vitro assays using bioluminescence of the bacterium Aliivibrio fischeri and the proliferation, viability, and integrity of human cells (adenocarcinomic human alveolar basal epithelial cell line A549). The general practice in the CMP industry is to dilute the slurry waste stream so actual abrasive concentrations are typically orders of magnitude smaller than 1 mg mL−1, which is lower than IC-50 levels. In contrast to recent reports, we observed similar toxicological characteristics between c-SiO2 and f-SiO2, and the materials exhibited similar X-ray diffraction (XRD) spectra but different morphology observed using electron microscopy. The ENPs and CMP slurries used in this study have been made available to a number of other research groups, and it is the intention of the consortium for this paper to provide a basis for characterizing and understanding human and environmental exposures for this important class of industrial ENPs.

Nanomaterials (NM) of silica (SiO 2 ), cerium (CeO 2 ), and alumina (Al 2 O 3 ) are used in liquid slurries by a number of industrial applications, including chemical mechanical polishing/planarization (CMP) processes used multiple times during production of computer chips. These NM are designed to be dispersed in the CMP slurries, which are used once and subsequently discharged to sewers. The global production of these three NM CMP slurry materials exceeds 5000 ton/year, placing them among the highest nanomaterial production volumes worldwide. Industrial on-site treatment of NM is not part of most discharge permits, but some semiconductor facilities apply on-site treatment for other limits related to metals (e.g., arsenic, copper), turbidity, and/or biochemical oxygen demand. This chapter characterizes commonly used CMP NM, investigates removal efficiency using a representative industrial on-site treatment strategy (chemical softening and precipitation), and off-site treatment at biological wastewater treatment plants. We also demonstrate the use of techniques to characterize NM in liquid solutions, including the ability to separate dissolved from NM forms of silica. Overall, the results provide information on a large production volume NM waste stream that has the potential to enter the environment.