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• NaOH and trisilanolphenyl polyhedral oligomeric silsesquioxane (TPOSS) were used as catalysts to synthesize a novel boron-containing phenolic resin (TBPR). • NaOH/TPOSS results in more para -methylene linkage in TBPR structure, which is the key to the remarkable initial decomposition temperature. • The morphological transformation of TBPR at different temperatures was studied to verify the role of Si and B on the thermal pyrolysis stability. • CF/TBPR shows an outstanding ablative resistance due to the remakable thermal stability of TBPR. The heat resistance of existing phenolic resins cannot meet the requirements of the increasingly harsh spaceflight environment. Boron and silicon have been added to phenolic resins to improve the char yields. However, achieving both a high initial decomposition temperature and an outstanding char yield remains challenging. This study presented a strategy to regulate the methylene types of boron-containing phenolic resin (TBPR) by trisilanolphenyl polyhedral oligomeric silsesquioxane (TPOSS) and NaOH. Thermogravimetric analysis (TGA) in nitrogen of cured TBPR displayed remarkable thermal stability with an initial decomposition temperature of 450.0 °C and a char yield of 75.8 %. The effect of TPOSS and NaOH on the TBPR structure were further investigated using nuclear magnetic resonance (NMR) analysis and density functional theory (DFT) calculation. The results indicated that TPOSS could attract sodium phenate and formaldehyde through hydrogen bonds, and greatly reduced the energy barrier of the phenol–formaldehyde resin para -addition. The formation of more p-p' type methylene structures of phenolic resin profoundly contributed to the outstanding initial decomposition temperatures and char yield. TBPR matrix transformed into a stronger protective char layer, forming an effective thermal protection barrier. As a result, the mechanical strength and ablative resistance of the fiber-reinforced CF/TBPR composites were enhanced by the excellent thermal stability of TBPR matrix. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like MoS 2 sheets were encapsulated into the interlayer of N-doped graphene. • The FL-MoS 2 /N-G enables the high loading of MoS 2 and good structural integrity. • The MoS 2 sheets coupled with N-doped graphene can accelerate the charge transfer. • The encapsulation structure of FL-MoS 2 /N-G has low diffusion resistance of Li+ ions. • The target FL-MoS 2 /N-G anode exhibits superior performance for Li+ ion storage. Layered molybdenum disulfide (MoS 2) is a promising anode material for lithium-ion storage and its coupling with graphene can further improve the specific capacity and cycling stability. In this work, a feasible polyacrylamide (PAM)-assisted approach to prepare the flower-like MoS 2 nanosheets encapsulated by nitrogen-doped graphene (FL-MoS 2 /N-G) is proposed. The PAM is taken as the directing agent for the layered assembly of graphene and further confined growth of FL-MoS 2 in the interlayers of the graphene. The unique encapsulation construction of MoS 2 and N-doped graphene leads to the high loading of active species and stabilized structural integrity after the continuous Li+ ion intercalations. Theoretical simulation results reveal that the MoS 2 nanosheets coupled with N-doped graphene can accelerate the charge transfer process and create extra lithiation sites with decreased diffusion resistance of Li+ ions. As the anode material in lithium-ion batteries (LIBs), the target FL-MoS 2 /N-G composite exhibits a high reversible capacity of about 1202 mAh g−1 at 0.2 A g−1 and it can remain 835 mAh g−1 even at 5 A g−1, highlighting an excellent rate capacity. Additionally, the FL-MoS 2 /N-G anode is also capable of delivering a long-term cycling performance with a capacity retention of about 78% after 800 cycles. Furthermore, benefiting from the fast charge transfer process of the FL-MoS 2 /N-G dominated by surface capacitive behavior, the lithium-ion hybrid capacitor with good electrochemical performance was fabricated to brighten its practical application prospect. The current work presents a new insight into the fabrication of high-loading MoS 2 /N-doped graphene composites with unique nanostructures for high-performance lithium-ion storage. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse obtained from sugar industry was efficiently delignified by pretreatment, including Fenton reaction and ultrasound-assisted NaOH, and then was applied to the biotransformation of edible macrofungus to obtain mycelial growth with efficient substrate utilization and value-added bioactive compounds production. [Display omitted] • FT/NA-US pretreatment is useful for delignification of lignocellulose in SCB. • Delignified SCB benefit for the macrofungi with low lignin-degrading capacity. • Pretreated SCB promotes macrofungal growth and secondary metabolites formation. • Alkali provides detoxification effect on bio-inhibitor produced by Fenton in SCB. Sugarcane bagasse (SCB), a widely available lignocellulosic by-product, could be potentially used in macrofungal bioconversion for high-value bioactive compounds. For macrofungus with poor lignin degradation capacity, its recalcitrant lignin structure blocked the release of fermentable sugars for cell growth. Herein, the main objective was to construct an effective delignification pretreatment strategy for SCB biotransformation and synthesis of bioactive substances by Agaricus sinodeliciosus var. Chaidam. Different pretreatments including chemical (alkali and Fenton oxidation) and ultrasound methods were used to intensify the delignification process. Physico-chemical characteristics of native and pretreated SCB were examined via XRD, XPS, FT-IR and 13C ssNMR to characterize crystallinity index, surface lignin and chemical structure. Lignocellulose-degrading enzymes were also used to assess the ability of the macrofungus to degrade SCB. By comparing morphological structure, chemical composition and fermentation characteristics, a suitable multiple sequential pretreatment method was finally identified. Our findings revealed that Fenton-ultrasound-alkali pre-treatment has an optimum delignification effect on SCB with never-uncovered excellent ability to detoxify harmful substances produced by Fenton oxidation. Under this pretreatment condition, the cellulose content was increased by 106.45%, whereas hemicelluloses and lignin were decreased by 48.34% and 74.15%, respectively. The macrofungal growth, intracellular polysaccharides, total phenols and terpenoids formation were 2.4, 1.46, 1.36 and 1.66 times higher than those of the untreated, respectively. Fermentation kinetic results showed outstanding fit and prediction of macrofungal growth and enzymatic activity secretion on above pretreated SCB. This study shed light on developing a novel pretreatment strategy for low-cost SCB lignocellulose transformation into high-value products. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Fe SACs with the asymmetric Fe-N 5 moiety anchored on GCNC were fabricated. • The Fe-N 5 /GCNC is capable of adsorbing LiSPs and accelerating their redox kinetics. • The Li-S cell with the Fe-N 5 /GCNC@PP separator exhibits superior cycling stability. • The assembled device shows an areal capacity as high as 4.49 mAh cm−2 at 0.2C. Lithium-sulfur (Li-S) batteries with extremely high theoretical energy density are expected to be the next-generation energy storage systems. However, the electrochemical performance of Li-S batteries is still restricted by the shuttle effect of lithium polysulfides (LiPSs) resulting from their sluggish conversion kinetics. Herein, we demonstrated a coordination-confinement-pyrolysis strategy to fabricate iron single-atom catalysts (Fe SACs) supported on graphitic carbon nanocapsules (GCNC) by using imine (-RC = N-)-enriched polymer as precursors, aiming at suppressing the shuttle effect in Li-S batteries via simultaneously enhancing LiPSs confinement and catalytic conversion. The in-depth experiment investigations have revealed that the as-obtained N -doped carbon nanocapsules with ample hollow channels and large specific surface area (SSA) enable efficient adsorption and confinement for LiPS intermediates. Further, the isolated Fe SACs anchored on highly conductive graphitic carbon frameworks show an asymmetric N -coordinated active moiety (Fe-N 5) that ensures fast redox kinetics of LiPSs and solid Li 2 S/Li 2 S 2 products. As a result, the Li-S cell with a functional separator modified by the Fe-N 5 /GCNC exhibits a much-increased specific capacity of 1125 mAh/g at 0.1 C, excellent rate capability of 627 mAh/g at 2 C, and remarkable long-term cycling stability with a low capacity decay of 0.0386 % per cycle upon 1000 cycles. This work presents a useful strategy to fabricate high-activity SACs coupled with hollow graphitic carbon frameworks and to accelerate the catalytic conversion kinetics of LiPS intermediates for high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • N -doped carbon nanosheets were fabricated via a facile templating-assisted strategy. • The N -doped carbon nanosheets showed superior performance in redox electrolytes. • Graphitic N on the carbon scaffolds can accelerate the redox kinetics of iodides. The incorporation of redox-active anions into aqueous electrolytes endows electrodes with enhanced specific energy density for supercapacitors. However, the congruent relationship between the redox chemistry of electrolytes and electrode surfaces is still not well understood. Herein, two-dimensional nitrogen-doped porous carbon nanosheets (denoted as NC- x with x being the carbonization temperature in Degree Celsius) are systematically synthesized by using general dual-crystals templating assisted strategy with pore structure and surface composition optimized. Employed as both positive and negative electrodes, the as-prepared NC-900 with a large specific surface area and ample graphitic N sites shows a high specific capacitance of 251 F g−1 with a voltage window of 1.6 V and energy density of 22.4 Wh kg−1 associated with 86.5% capacity retention after 30,000 cycles using aqueous iodide redox electrolyte. The experimental and theoretical analyses reveal the contributions of nitrogen configurations on the carbon scaffolds to accelerate the redox chemistry of iodides. The enhanced redox performance of the porous carbon nanosheets is linearly proportional to the graphitic N content, which is consistent with the large electron-donating area and the strong adsorption capacity towards iodine species at the graphitic N sites. This work shows a new design strategy of carbon electrodes for high-performance supercapacitors with the aqueous redox electrolytes. [ABSTRACT FROM AUTHOR]

Rational design and manufacture of encapsulated Pt@HCS catalysts for efficient benzene elimination under SO 2 containing conditions. [Display omitted] • Pt nanoparticles are uniformly encapsulated in a hollow carbon shell. • Pt@HCS shows excellent benzene oxidation properties, even in the presence of SO 2 , the benzene conversion rate can be stable at 100% for a long time. • The porous hollow carbon sphere structure significantly enhances the adsorption of benzene. • The abundant OH groups on the carbon shell surface preferentially capture SO 2 and prevent it from entering the interior of the catalyst. In the catalytic combustion of volatile organic compounds (VOCs) using noble metal catalysts, resistance to SO 2 poisoning poses a significant challenge. To tackle this problem, Pt nanoparticle catalysts encapsulated in hollow carbon spheres (Pt@HCS catalysts) are synthesized. The Pt@HCS catalyst exhibits excellent benzene conversion, achieving 100 % conversion at 165 °C under an air velocity of 20,000 mL/(g h). Compared to the conventional supported Pt/HCS catalyst, the Pt@HCS catalyst demonstrates a significantly improved resistance to SO 2 poisoning. In the presence of 25 ppm SO 2 , the Pt@HCS catalyst is capable of maintaining a 100 % benzene conversion rate within 24 h, whereas the conversion rate of Pt/HCS drops substantially to approximately 52 %. It is confirmed that the hollow porous structure provided a larger specific surface area and more adsorption sites, thereby facilitating benzene oxidation. More importantly, in situ DRIFTS reveals that the adsorption and desorption processes of SO 2 , along with the generation of substances like SO 3 2−, are strictly limited to the surface of the carbon shell, thereby preserving the integrity of the internal reaction environment. Multiple characterizations combined with density functional theory (DFT) have demonstrated a unique separation effect over Pt@HCS, whereby the hydroxyl groups on the carbon shell preferentially capture SO 2 while allowing benzene molecules to enter the cavities of the catalyst. In this way, any internal ingress of SO 2 and competition with benzene for Pt adsorption is effectively avoided. This study offers a potential solution to enhance the performance of noble metal catalysts in the presence of sulfur compounds. [ABSTRACT FROM AUTHOR]

• Lanthanide metal Nd-evoked valence electronic modulation of Co in Co@NC nanocubes. • Nd-doping induces defect sites and hydrophibicity regulation of Co@NC nanocubes. • Enhanced degradation activity and reusability of Nd/Co@NC-0.2 for 4-NP is obtained. • Radical/non-radical and direct electron transfer pathway are detected in the system. • Toxicity of intermediates and degradation pathways by the system are unveiled. Metallic Co-based materials are widely recognized as benchmark catalysts for the degradation of organic pollutants. However, they still suffer from relatively low stability and reusability, necessitating the development of efficient regulation strategies. In this study, we propose a unique and effective approach using neodymium (Nd)-mediated valence electronic and surface microenvironment regulation to enhance the catalytic properties of Co/N-doped carbon cubes for the degradation of 4-nitrophenol (4-NP) via peroxymonosulfate (PMS) activation. The strong coordination between the negatively charged organic ligands and positively charged Nd and Co metal ions ensures the intense coupling of Nd and Co sites in the synthesized sample through pyrolysis. Notably, the incorporation of Nd not only modulates the valence electronic properties of Co sites but also increases the defect degree, surface hydrophobicity, and conductivity of the resulting material. These enhancements are responsible for the high-performance degradation of 4-NP through PMS activation. The optimal Nd/Co@NC-0.2 catalyst achieves a remarkable degradation efficiency of 95 % within 20 min, while also exhibiting enhanced stability and reusability. Furthermore, our developed system demonstrates good tolerances to different conditions, solution pH and inorganic/organic substances. The degradation system involves both radical/non-radical and direct electron transfer pathways. We also unveil the reaction intermediates, their toxicities and the degradation pathways catalyzed by the Nd/Co@NC-0.2/PMS system. This study presents a novel strategy utilizing lanthanide metal-evoked regulation to enhance capability of Co-based catalysts for PMS activation towards the degradation of harmful organics. [ABSTRACT FROM AUTHOR]

[Display omitted] • The conductive PEDOT skin on the NiCo-LDH is fabricated by the oCVD strategy. • The presence of PEDOT skin results in uniform distribution of electrical potential. • The PEDOT layer enables a low desorption energy of hydrogen for redox reactions. • The as-obtained LDH/PEDOT- 10 electrode shows superior electrochemical performance. Transition metal hydroxides with tuned structure and superior electrochemical activities are of potential as positive electrodes for aqueous hybrid supercapacitors (AHSs), yet their conductivities and stacking behaviors need to be optimized to further improve the electrical potential distribution from the electronic multi-contact border to the electroactive center. Herein, we report a new approach to coat poly(3,4-ethylenedioxythiophene) (PEDOT) skin with a controlled thickness on nickel–cobalt layered double hydroxide (NiCo-LDH) nanosheets via a simple yet efficient oxidative chemical vapor deposition (oCVD). The conductive PEDOT skin is ionically permeable, resulting in uniform distribution of the electrical potential and fast transport of ions to active sites. The density functional theory (DFT) calculations reveal that the PEDOT layer can build an embedded electric field at the interface and enable a low desorption energy of hydrogen for electrochemical redox reactions. The as-obtained NiCo-LDH nanosheets with the PEDOT skin of 10 nm thick (LDH/PEDOT- 10) as the battery-type electrode deliver a high specific capacity of 167 mAh g−1 (1250F g−1) with a greatly improved rate capability of 79 % at 50 A g−1 and cycling stability of 92 % for 6000 cycles, which endows AHS devices with superior charge-storage performance. This study has demonstrated for the first time that the modulation of electrical potential for redox electrodes via an interface engineering strategy can achieve simultaneously fast reaction kinetics and excellent structure stability for aqueous energy-storage devices. [ABSTRACT FROM AUTHOR]