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This work aimed to deeper insight into the interaction processes between lignin and holocellulose in lignocellulosic biomass. As a result, apricot shell lignin (ASL) and apricot shell holocellulose (ASH) were prepared. Subsequently, the thermal behaviors of apricot shell (AS), ASL, ASH, and ASL/ASH blends were determined by thermogravimetric analysis (TGA) using mass changes as a monitoring parameter. The activation energy was calculated by employing the model-free integral methodology, and the reaction models were estimated using Criado mater plots (hereinafter referred to as mater plots). Additionally, using the resulting activation energies, the changes of pre-exponential factor (A), enthalpy (ΔH), Gibbs free energy (ΔG), and entropy (ΔS) were determined. When the weight ratio of ASL to ASH was below ~ 1.1, the degradation of ASL and ASH begins to show synergistic effects. Extractives and volatiles in ASH endow a significant effect on improving the reaction dynamics in co-pyrolysis processes, which was evidenced through an increase in decomposition intensity. Samples differ in their primary reaction mechanisms upon small (α≤ 0.5) and large (α≥ 0.5) conversion rates. Furthermore, there was a linear positive correlation between the Avalue and activation energy. Thermal decomposition of AS, ASL, ASH, and ASL/ASH mixtures afforded positive ΔGand ΔH.

Herein, the organic matter is reported to reduce the overpotential of oxygen evolution reaction (OER) for water splitting. Herein, osmium (Os) is doped into WO2.72to form Os–WO2.72as an electrocatalyst, which is applied into water splitting to produce hydrogen and assist promote glucose oxidization reaction (GOR). The OER overpotential of 0.05 Os–WO2.72is only 248 mV at 10 mA cm−2in 1 mKOH, which is much superior to commercial RuO2. Additionally, the 0.05 Os–WO2.72has ultralow GOR overpotential of 158 mV at 10 mA cm−2and 365 mV at 100 mA cm−2in 1 mKOH with 0.1 mglucose, and the cell voltage is 1.37 V at 10 mA cm−2, the values are much lower than its electrocatalytic behaviors in 1 mKOH. The anode produces gluconic acid, which is an important industrial intermediate during hydrogen production at the cathode. Herein, osmium (Os) is doped into WO2.72to form Os–WO2.72as the electrocatalyst to produce gluconic acid at anode and H2at cathode.

3D monolithic reactor has shown great promise for varied heterogeneous catalysis reactions including water treatment, energy generation and storage, and clean fuel production. As a natural porous material, macroporous wood is regarded as an excellent support for inorganic catalyst due to its abundant polar functional groups and channels. On the other hand, a metal organic framework (MOF) has been widely used as heterogeneous catalyst due to its high specific surface area and large amount of microporosities. Combining macroporous wood and a microporous MOF is expected to produce a high-performance 3D reactor and is demonstrated here for Fischer–Tropsch synthesis. The carbonized MOF/wood reactor retains the original cellular structure with over 180 000 channels/cm2. When being decorated with hexagonal-shaped core–shell Co@C nanoparticles aggregates derived from Co-MOF, the MOF/wood reactor resembles a multi-cylinders reactor for Fischer–Tropsch synthesis. Because of the unique combination of macro- and microporous hierarchical structure, the 3D MOF/wood reactor demonstrates exceptional performance under high gas hourly space velocity (81.2% CO conversion and 48.5% C5+selectivity at 50 L·h–1·gcat–1GHSV). This validates that MOF/wood can serve as a multi-cylinders and high-power reactor for catalytic reactions, which is expected to be applicable for environmental and energy applications.

Because of the prevailing environment and energy challenges, there has been a growing interest in biobased materials for thermal insulation application. Although cellulose aerogel has been considered as an excellent thermal insulating material, its thermal conductivity is generally negatively affected by the interconnected internal pores. Herein, it is demonstrated that a cellulose nanofibril (CNF)/emulsion composite aerogel with quasi-closed internal pores can be facilely fabricated by Pickering emulsion templating and solvent exchange methods. The CNF-stabilized oil-in-water Pickering emulsion (with an average diameter of 1.3 μm) can be converted into quasi-closed pores by sequential solvent exchange to acetone and tert-butanol (TBA), followed by freeze-drying from TBA to suppress the formation of large ice crystals. The presence of quasi-closed pores from emulsion templating is verified by both confocal microscopy and scanning electron microscopy images and is confirmed to reduce thermal conductivity to as low as 15.5 mW/(m K). Compared to the CNF aerogel, increasing emulsion content can lead to better volume retention with significantly reduced density (11.4 mg/cm3), increased mesoporosity, and enhanced specific modulus (18.2 kPa/(mg/cm3)) and specific yield strength (1.6 kPa/(mg/cm3)). In addition, the CNF/emulsion composite aerogel also demonstrates superb flexibility and infrared shielding performance.

Proton exchange membrane water electrolysis (PEMWE) is considered an ideal green hydrogen production technology with promising application prospects. However, the development of efficient and stable acid electroanalytic oxygen electrocatalysts is still a challenging bottleneck. This progress is achieved by adopting a strategic approach with the introduction of the high valence metal Ta to regulate the electronic configuration of RuO2by manipulating its local microenvironment to optimize the stability and activity of the electrocatalysts. The Ta-RuO2catalysts are notable for their excellent electrocatalytic activity, as evidenced by an overpotential of only 202 mV at 10 mA cm–2, which significantly exceeds that of homemade RuO2and commercial RuO2. Furthermore, the Ta-RuO2catalyst exhibits exceptional stability with negligible potential reduction observed after 50 h of electrolysis. Theoretical calculations show that the asymmetric configuration of Ru–O–Ta breaks the thermodynamic activity limitations usually associated with adsorption evolution, weakening the energy barrier for the formation of the OOH* formation. The strategic approach presented in this study provides an important reference for the development of a stable active center for acid water splitting.

This work suggests how understanding the Gibbs free energy evolution mechanism recorded for solid activators at high temperatures can provide a simple and general route to targeted tuning in preparing porous carbons. We show that based on a novel spatial confinement strategy, it is likely to target-produce pine sawdust (PS)-derived porous carbons characterized by higher specific surface area than analogous conventionally porous carbons but similar average pore size and pore size distribution (PSD). Notwithstanding the increased specific surface area and total pore volume of PS-derived porous carbon prepared under spatial confinement forces compared to conventional porous carbon, the pore structures recorded for PS-derived porous carbon obtained under spatial confinement forces arise from narrow pores, which leads to a sharp growth in specific capacitance over a range. Specifically, the texture properties can be tuned by various spatial confinement forces, bypassing the activation process tuning, template, sequential activation, and trial-and-error methods. Notably, PC-40-850 achieved higher specific capacitance values. Encouragingly, PC-40-850 offered excellent cycle stability accompanied by great energy density values (e.g., 29.31 Wh/kg upon 499.99 W/kg). Specifically, PC-40-850 realized a surface area-normalized electrical double-layer capacitance of 65.93 mF/m2. Excellent manufacturability and variable narrow-pore distribution permit the spatial confinement strategy to produce numerous advanced and multistage porous carbons for matching specific applications.

Utilizing and reducing carbon dioxide is a key target in the fight against global warming. The photocatalytic performance of bulk graphitic carbon nitride (g-C3N4) is usually limited by its low surface area and rapid charge carrier recombination. To develop g-C3N4more suitable for photocatalysis, researchers have to enlarge its surface area and accelerate the charge carrier separation. In this work, novel hybrid graphitic carbon nitride and carbon (H-g-C3N4/C) composites with various carbon contents have been developed for the first time by a facile one-step pyrolysis method using melamine and natural soybean oil as precursors. The effect of carbon content on the structure of H-g-C3N4/C composites and the catalytic activity for the photoreduction of CO2with H2O were investigated. The results indicated that the introduction of carbon component can effectively improve the textural properties and electronic conductivity of the composites, which exhibited imporved photocatalytic activity for the reduction of CO2with H2O in comparison with bulk g-C3N4. The highest CO and CH4yield of 22.60 μmol/g-cat. and 12.5 μmol/g-cat., respectively, were acquired on the H-g-C3N4/C-6 catalyst with the carbon content of 3.77 wt % under 9 h simulated solar irradiation, which were more than twice as high as that of bulk g-C3N4. The remarkably increased photocatalytic performance arises from the synergistic effect of hybrid carbon and g-C3N4.

Magnesium silicon nitride (MgSiN2) nanoparticles have been synthesized by using magnesium silicide (Mg2Si), sodium azide (NaN3) and sulfur as starting materials in a stainless steel autoclave at relatively low temperature. X-ray powder diffraction patterns indicate the obtained products are orthorhombic phase MgSiN2. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images reveal that the average size of product is 40 nm. The oxidation resistance of the obtained MgSiN2nanoparticles has been investigated.Magnesium silicon nitride (MgSiN2) nanoparticles have been synthesized by using magnesium silicide (Mg2Si), sodium azide (NaN3) and sulfur as starting materials in a stainless steel autoclave at relatively low temperature.

In this study, Ni2Mo3N cube-like particles have been synthesized by a solid-state reaction of metallic molybdenum, nickel chloride hexahydrate, and sodium azide in a sealed autoclave at 750 °C. The structures and morphologies of the obtained product are derived from X-ray diffraction, field-emission scanning electron microscopy, and transmission electron microscopy. Furthermore, the thermal stability and oxidation resistance of the obtained product are investigated.Ni2Mo3N cube-like particles have been synthesized by a solid-state reaction of metallic molybdenum, nickel chloride hexahydrate, and sodium azide in a sealed autoclave at 750 °C. All the reflection peaks in Figure 1 can be indexed to the pure cubic structure of Ni2Mo3N with calculated lattice constants a= 6.6429 Å.