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Smart textiles are attracting increasing attention due to their tremendous applications in wearable devices. Herein, we report a flexible and conductive textile prepared via simple “dipping and drying” method with Ag nanowires (Ag NWs) ink. The obtained Ag NWs/cellulose textiles have very high conductivity(sheet resistance 0.2 Ω/sq) and excellent chemical and mechanical stabilities, showing great potential in wearable energy storage and photothermal conversion. The supercapacitor made from the Ag NWs/cellulose textile showed a higher capacitance (159 F g −1 ) than the textiles functionalized with single-walled carbon nanotube (SCNT) and graphene. Besides, they presented excellent photothermal conversion property with about 50% improvement in temperature compared with pure textile. These multifunctional textiles would provide new opportunities for flexible and wearable electronics and sensors. [ABSTRACT FROM AUTHOR]

Dried wheat straw was treated with acetic anhydride at 100 and 120 °C for 40–360 min with four tertiary amine catalysts (pyridine, 4-dimethylamino pyridine, N-methyl pyrrolidine, and N-methyl pyrrolidinone) or without catalyst in a solvent-free system, and the extent of acetylation was measured by weight percent gain. 4-Dimethylamino pyridine was found to be the most effective catalyst of those studied. The characterization of acetylated straw was performed by FT–IR, CP–MAS 13C–NMR, and thermal studies. FT–IR and CP–MAS 13C–NMR studies produced evidence for acetylation. The thermal stability of acetylated wheat straw was found to be higher than the native straw. More importantly, the acetylation significantly increased the hydrophobic properties of the straw. The oil sorption capacities of the acetylated straws were much higher (1.2–2.9 times) than the commercial synthetic oil sorbents such as polypropylene fibres. Acetylated straw can therefore be used as a substitute for non-biodegradable materials in oil-spill cleanup. To cite this article: R.C. Sun et al., C. R. Chimie 7 (2004). [Copyright &y& Elsevier]

The present study was undertaken to investigate the extractability of the hemicelluloses from bagasse obtained by ultrasound-assisted extraction methods. The results showed that the ultrasonic treatment and sequential extractions with alkali and alkaline peroxide under the conditions given led to a release of over 90% of the original hemicelluloses and lignin. This fact as well as the sugar composition and structural features of the isolated seven hemicellulosic fractions indicated that ultrasonication attacked the integrity of cell walls, cleaved the ether linkages between lignin and hemicelluloses, and increased accessibility and extractability of the hemicelluloses. Increasing alkali concentration from 0.5 to 2 M and alkaline peroxide percentage from 0.5% to 3.0% resulted in degradation of hemicellulosic backbone as shown by a decrease in their molecular weights from 43,580 to 14,470 and 30,180 to 18,130 g mol−1, respectively. However, there were no significant differences in the structural features of the seven sequential alkali- or alkaline peroxide-soluble hemicellulosic fractions, which are composed mainly of l-arabino-(4-O-methyl-d-glucurono)-d-xylans. Ferulic and p-coumaric acids were found to be chemically linked with hemicelluloses. [Copyright &y& Elsevier]

Highly purified cellulose was separated from wheat straw by sequential treatments of dewaxed straw with 0.5-M aqueous KOH at 35°C for 2.5 h under ultrasonic irradiation time of 0 to 35 min, 2% H2O2–0.2% TAED at pH 11.8 for 12 h at 48°C, and with 80% acetic acid–70% nitric acid (10/1, v/v) at 120°C for 15 min. The yield of crude cellulose preparations obtained by first two-stage treatments ranged between 45.3% and 46.9% of the dry weight straw which contained 7.3 to 7.9% residual hemicelluloses and 3.3 to 3.7% residual lignin, and had molecular weights ranging from 269,960 and 258,280 g mol−1 determined by their viscosity, while the purified cellulose samples separated by a further treatment of the corresponding crude cellulose with 80% acetic acid–70% nitric acid, are relatively free of bound lignin (0.1 to 0.2%) and contained minor amounts of associated hemicelluloses (∼3%), but gave much lower molecular weights ranging between 42,300 and 44,650 g mol−1 estimated by GPC in DMAc/LiCl system indicating that the final step treatment with 80% acetic acid–70% nitric acid resulted in a noticeable degradation of the cellulose except for removal of residual hemicelluloses and lignin. However, there was no evidence of increased acid or aldehyde by oxidation in all the purified cellulosic preparations. Both crude and purified cellulose samples were characterized by FT-IR and CP/MAS 13C-NMR spectroscopy. The thermal stability of the purified cellulosic preparation was higher than that of the crude cellulosic sample. [ABSTRACT FROM AUTHOR]

Post-treatment with 2% H2O2–0.2% tetraacetylethylenediamine (TAED) at pH 11.8 for 12 h at 48 °C solubilized 27.1–28.1% of the original hemicelluloses and 43.3–46.2% of the original lignin from the ultrasound irradiated and alkali pre-treated wheat straw. It was found that the bleaching activator TAED forms peracetic acid with hydroperoxide anion in aqueous alkali and improves the brightness of the solubilized hemicelluloses. Xylose was a predominant sugar in all the hemicellulosic preparations, comprising 72.0–73.1% of the total sugars. Arabinose (13.4–13.9%) and glucose (6.7–7.9%) were detected as the second and third major neutral sugar constituents. In addition, the hemicelluloses also contained a noticeable amount of 4-O-methyl-d-glucuronic acid (6.0–7.0%) together with a small amount of galactose (4.3–4.9%) and minor quantities of rhamnose (1.5–1.8%) and mannose (0.5–0.8%). Furthermore, the hemicellulosic preparations obtained by TAED activated peroxide extraction showed a relatively lower content of associated lignin (3.8–4.4%), but a higher molecular weight (34,210–40,310 g mol−1). No significant differences in the structural features such as oxidation of the hemicelluloses by TAED were observed as compared to those obtained by alkaline peroxide without bleaching activator. [Copyright &y& Elsevier]

Post-treatment of ultrasonic irradiated and alkali pre-treated wheat straw with TAED activated peroxide at pH 11.8 for 12 h at 48 °C resulted in a dissolution of 43.3–46.2% of the original lignin and 27.1–28.1% of the original hemicelluloses, respectively. The isolated acid-insoluble lignin preparations were analysed by both destructive methods such as alkaline nitrobenzene oxidation and non-destructive techniques such as UV, FT-IR, and 13C NMR spectroscopy as well as GPC. Total polysaccharide content of isolated lignin preparations ranged from 0.79 to 1.01%. Nitrobenzene oxidation analysis showed that the molar ratio of V:S:H in the eight lignin preparations was 6:5:1. In addition, the residual lignins isolated by TAED activated peroxide showed a higher molecular weight and thermal stability than the lignins released during the pre-treatment with alkali combining with or without ultrasonic assistance. Furthermore, it was found that more hydroxyl, aldehyde and ketone groups and aryl ethers in the lignin side chains were attacked with the use of TAED. [Copyright &y& Elsevier]

The chemical modification of rice, wheat, rye, and barley straws, and poplar wood fibre using acetic anhydride at different time and temperatures in the absence of solvent and catalyst has been investigated. It was found that the weight percent gain increased with an increment of reaction temperature and time, and the fastest rate of reaction occurred during the initial 1 h acetylation process. The characterization of acetylated straws and poplar wood fibre was performed by FT-IR, solid-state 13C-NMR, and thermal studies. Thermal stability of acetylated straws was found to be higher than the unmodified straws. [Copyright &y& Elsevier]

Eight white residual hemicellulosic preparations were obtained by post-treatment with TAED activated peroxide (2% H 2 O 2 –0.2% TAED at pH 11.8 for 12 h at 48 °C) from the ultrasonic irradiated and alkali organosolv pre-treated wheat straw. It was found that the post-treatment under the condition given released 44.5–53.5% of the original hemicelluloses and 14.8–30.8% of the original lignin. All the hemicelluloses extracted by TAED activated peroxide were lighter in colour than those obtained under similar conditions but in the absence of TAED. In comparison, the isolated eight hemicellulosic samples were analysed by both degraded methods such as acid hydrolysis and alkaline nitrobenzene oxidation, and non-degradation techniques e.g. FT-IR and 13 C-NMR spectroscopy, and gel permeation chromatography. Results showed that the post-treatment with TAED activated peroxide did not oxidize the hydroxyl groups in hemicelluloses and neither affect the overall structure of the macromolecules. Thermal stability of the residual hemicellulosic samples was studied using thermogravimetric analysis and differential scanning calorimetry. [ABSTRACT FROM AUTHOR]

Treatment of solvent extracted wheat, rice, rye, and barley straws, maize stems, and fast-growing poplar wood with 60% aqueous ethanol in 0.2 M HCl at 75 °C for 3 h released 51.8, 51.2, 47.2, 43.7, 54.0, and 16.7% of the original lignin, and 44.3, 50.3, 30.9, 36.1, 40.0, and 25.5% of the original hemicelluloses, respectively. It was found that the bulk of p-coumaric acid (PCA) (67.0–83.5%) was esterified at the lignin side chains, while ferulic acid (FA) is linked to lignin side chains through both ether bonds (51.6–68.3%) and ester bonds (31.7–48.4%), indicating that FA may form intra- and/or inter-molecular ester–ether bridges between lignin fragments, which is first proposed in this study. In addition to p-hydroxybenzoic acid esterified to lignins in the cell walls of wheat straw and fast-growing poplar wood, a small portion of ether-linked p-hydroxybenzoic acid in the lignin preparations, obtained from rice, rye, and barley straws and maize stems, was also detected. It was also detected that noticeable amounts of syringic and vanillic acids were predominantly esterified to the lignin molecules in the cell walls of the materials studied. [Copyright &y& Elsevier]

Five lipophilic extractives isolated with toluene–ethanol (2 : 1, v/v), chloroform, petroleum ether, dichloromethane, and hexane from rice straw were examined by Fourier transform infrared, 1H and 13C nuclear magnetic resonance spectroscopies, and thermal analysis. In comparison with other four extractives, the extractives, isolated with toluene–ethanol (2 : 1, v/v), showed much lower absorption bands at 2926 and 2853, and 1739 and 1713 cm-1 for CH2 and CH3 stretching frequencies, and C=O stretching in ester and acids, indicating a much lower content of the lipophilic substances in the extractives. A rather weak band at 1030 cm-1 in the extracts, isolated with petroleum ether and dichloromethane, indicated that the two extracts were relatively free of co-extracted polysaccharides. The thermal analysis showed that the melting temperatures of the extractives occurred between 57.1 and 71.4°C, indicating a mixture of the extracts. [ABSTRACT FROM AUTHOR]

Barley straw was extracted with toluene-ethanol (2:1, vol/vol), chloroform, methyl tert-butyl ether (MTBE), hexane-acetone (2:1, vol/vol), and dichloromethane for 12 hours in a Soxhlet. The 51 individual compounds in 5 lipophilic extracts were separated by gas chromatography. Free fatty acids (15.18–38.20%), sterols (1.41–10.42%), waxes (3.45–11.87%), steryl esters (5.04–24.70%), and triglycerides (1.16–10.03%) were identified as the major 5 classes of lipids in the barley straw extracts. Minor components such as diglycerides (0.07–0.89%) and resin acids (0.12–0.57%) were also verified from the straw lipophilic extracts. Nonlipids detected from the barley straw extracts were composed of minor amounts of phenolic compounds (0.17–2.05%), noticeable amounts of azelaic and maleic acids (0.48–15.06%), and some quantities of co-extracted polysaccharides, ash, or salts. Of the individual compounds in each group, 16 free fatty acids, 5 steryl esters, 3 sterols, 3 triglycerides, and 2 waxes were quantitatively determined. Extraction with MTBE gave the lowest yield of total extracts (1.19%) but contained the highest amounts of lipophilic extracts (81.04%), which were enriched with steryl esters (24.70%), free fatty acids (23.60%), waxes (11.22%), sterols (10.42%), and triglycerides (10.03%). In contrast, extraction with 2:1 toluene-ethanol produced the highest quantities of total extracts (3.92%) but of the lowest purity of the lipid substances (49.69%) and were comprised mainly of free fatty acids (38.20%) and nonlipid substances such as maleic and azelaic acids (15.06%), phenolic compounds (1.89%), and noticeable amounts of released polysaccharides, ash, or salts. [ABSTRACT FROM AUTHOR]

The polysaccharides in the cell walls of dewaxed poplar chips were separated into hemicellulose–lignin complexes (HLC), residual hemicelluloses, and cellulose by extraction with sodium hydroxide at various concentrations. Celluloses (43.9–44.5%), HLC (17.4–21.9%), and residual hemicelluloses (4.3–9.0%) were the major polysaccharide components. Initial extraction of the dewaxed poplar chips with 5% NaOH at 50°C for 4, 6, 8, and 12 hr, and 7.5 and 10% NaOH at 50°C for 6 hr yielded 17.4, 18.2, 18.4, 18.6, 20.3, and 21.9% HLC, respectively. Further extraction of the corresponding alkali-treated and delignified poplar chips with 17.5% NaOH–1% Na2B4O7·10H2O at 20°C for 2 hr released 9.0, 8.2, 7.9, 7.2, 5.5, and 4.3% residual hemicelluloses, respectively. Xylose was found to be a predominant sugar component (84.3–90.5%) in all of the more linear, acidic, and larger molecular size HLC preparations (, 26,090–40,500 g·mol-1), in addition to 4.0–4.8% bound lignin. These lignin molecules were found to be chemically linked to hemicelluloses mainly via syringyl units. On the other hand, all of the residual hemicellulosic fractions contained less xylose (57.3–59.1%) and less uronic acids (4.5–8.9%), but had a higher content of mannose (24.9–26.5%) and glucose (13.3–16.0%). In comparison with the HLC, the residual hemicellulosic fractions had a small molecular size (, 18,300–29,730 g·mol-1), and had less than half the amount of bound lignin (1.5–1.7%). These lignin molecules were associated with residual hemicelluloses mainly via guaiacyl units. All of the cellulose fractions were relatively free of noncellulosic sugars (contained more than 99.6% glucose), and no considerable degradation of the cellulose was observed under the various separation conditions given. [ABSTRACT FROM AUTHOR]

• Prior-fractionation selectively converts lignocellulose into chemicals and materials. • Advanced prior-fractionations for utilization of lignocellulose were reviewed. • Lignocellulose prior-fractionation in the industry was discussed. • Challenges and prospects in the utilization of lignocellulose were provided. Due to over-consumption of fossil resources and environmental problems, lignocellulosic biomass as the most abundant and renewable materials is considered as the best candidate to produce biomaterials, biochemicals, and bioenergy, which is of strategic significance and meets the theme of Green Chemistry. Highly efficient and green fractionation of lignocellulose components significantly boosts the high-value utilization of lignocellulose and the biorefinery development. However, heterogeneity of lignocellulosic structure severely limited the lignocellulose fractionation. This paper offers the summary and perspective of the extensive investigation that aims to give insight into the lignocellulose prior-fractionation. Based on the role and structure of lignocellulose component in the plant cell wall, lignocellulose prior-fractionation can be divided into cellulose-first strategy, hemicelluloses-first strategy, and lignin-first strategy, which realizes the selective dissociation and transformation of a component in lignocellulose. Ultimately, the challenges and opportunities of lignocellulose prior-fractionation are proposed on account of the existing problems in the biorefining valorization. [ABSTRACT FROM AUTHOR]

Photothermal elastomers are recognized as smart flexible materials that can rapidly and effectively convert light energy into heat energy. However, there has been a lack of adequate focus on tackling the sustainability challenges of photothermal elastomers, particularly in terms of material selection, the integration of complex functionalities, and final disposal. A fully bio‐derived photothermal elastomer (BPTE) produced through a simple and chemical‐free approach is introduced, utilizing alkali lignin, lipoic acid, and phytic acid as bio‐derived feedstocks. The BPTE exhibits an adaptive polymeric network crosslinked by dynamic covalent disulfide bonds and multiple hydrogen bonds, endowing it with dual‐mode photothermal conversion capability, robustness, stretchability, rapidly self‐healing property, hydrophobicity, swelling resistance, self‐adhesion, full recyclability, and degradability. The BPTE is further demonstrated as a next‐generation solution for photothermal generators, light‐driven actuators, photothermal antibacterial dressings, and photothermal fibers. The versatility of BPTE opens avenues for innovative smart devices and systems with significant potential in energy conversion, soft robotics, medical treatment, and smart clothing. With outstanding photothermal performances, full recyclability, and biodegradability, these fully bio‐based elastomers present an attractive prospect for the development of the advanced smart photothermal products. [ABSTRACT FROM AUTHOR]

[Display omitted] The shuttle effect, sluggish conversion kinetics, and uncontrollable lithium dendrites seriously hinder the practical application of lithium-sulfur (Li-S) batteries. Among many modified materials, covalent organic frameworks (COFs) stand out for their excellent ability to inhibit the shuttle effect, while their role in promoting lithium nucleation and catalyzing the conversion of sulfur species has been largely ignored. In this study, an integrated COF separator (TpPa@2400) is developed as a rapid lithium nucleator and sulfur species catalyst in fast-charging Li-S batteries. According to the adsorption energy and Bader charge results, Li atoms preferentially adsorb onto the surface of the TpPa@2400 separator, and the larger Bader charge value (0.52 |e|) of the TpPa@2400 separator also signifies faster lithium transport, promoting the nucleation of Li ions. Furthermore, density functional theory (DFT) theoretically demonstrates that the TpPa@2400 separator exhibits lower free energy for sulfur species interconversion. As a result, the TpPa@2400 separator enables the Li-Li symmetric cell with an extended cycle life of 6000 h at a current density/capacity of 10 mA cm-2/10 mAh cm-2. The Li-S battery assembled using the TpPa@2400 separator delivers a high capacity of 1636.4 mAh/g at 0.1C and a rapid sulfur species conversion capacity of 513.8 mAh/g at 2C. [ABSTRACT FROM AUTHOR]

Six lignin preparations, isolated by a novel two-step precipitation method instead of the traditional one-step precipitation method from the oil palm trunk fiber pulping (OPTFP) black liquor, were found to be relatively free of nonlignin materials such as polysaccharide degradation products, ash, and salts. A lignin fraction with a purity of 99.5% was obtained at an optimum precipitation pH 1.5 after isolation of the non-lignin materials in ethanol. About 94% of the total lignin was recovered by this novel method at this condition, and the value of COD in the treated black liquor reduced significantly to lower 250. The isolated lignin fractions contained syringyl, guaiacyl, and p-hydroxyphenyl units in an approximate molar ratio of 16–20:4–5:1 on the basis of chemical and spectroscopic analysis. Small amounts of p-hydroxybenzoic acids were found to be esterified to lignin, while ferulic acids were associated to lignin by ether linkage. 13C-NMR indicated the presence of β-O-4 ether bonds, andβ-5 and 5–5′ carbon–carbon linkages between the lignin molecules. [ABSTRACT FROM AUTHOR]

Heterojunction photocatalysts receive significant interest due to their high performance and easy fabrication. An S-scheme heterojunction is developed on the basis of conventional type II heterojunctions, which can further promote charge separation and migration. In this work, a photocatalyst with a dual S-scheme heterojunction (denoted as C-s-ZIS/CN) is developed by the hybridization of CuInS2 quantum dot-sensitized ZnIn2S4 nanosheets and g-C3N4 nanosheets. CuInS2 quantum dot sensitization efficiently enhanced light absorption. Meanwhile, the unique charge migration pathway in the dual S-scheme heterojunction accelerated the separation and transfer of photogenerated carriers. The photocatalyst was innovatively employed in the simultaneous photocatalytic production of xylonic acid and CO. Under 10 W LED light irradiation (790 mW cm−2), the CO evolution rate reached a high of 228.94 μmol g−1 h−1. When a xenon lamp was employed, the CO evolution rate increased to 964.27 μmol g−1 h−1. Moreover, the optimal xylonic acid yield achieved was up to 58.56%. [ABSTRACT FROM AUTHOR]

Eutectogels are emerging as an appealing soft conductor for self‐powered sensing and the next generation of flexible human–computer interactive devices owing to their inherent mechanical elasticity and high ionic conductivity. However, it still remains a challenge to simultaneously achieve multi‐functional and multi‐response integrations through a facile and sustainable approach. Herein, a self‐healing, environment tolerant, intrinsically conductive, and recyclable eutectogel with multiple responses is developed via one‐step solar‐initiated polymerization of deep eutectic solvents (DESs) and ionic liquids (ILs). Abundant hydrogen bonds and ion‐dipole interactions impart eutectogels with high mechanical strength (8.8 MPa), ultra‐stretchability (>1100%), strong self‐adhesion (≈12 MPa), recyclability, and autonomously self‐healing ability. Furthermore, the intrinsically conductive eutectogels with appealing versatile sensations on strain, temperature, and humidity can serve as wearable sensors for wireless motion recognition and human–computer interaction control. More importantly, the eutectogel‐assembled single‐electrode triboelectric nanogenerator (TENG) exhibits extreme environment‐tolerant and fast self‐healable properties that contribute to maintaining excellent and stable electrical outputs in a wide work temperature range (approximately −40–60 °C), which appear to be promising in self‐powered flexible electronics with high environmental adaptability. [ABSTRACT FROM AUTHOR]

The application of lithium metal batteries is limited by the drawbacks of safety problems and Li dendrite formation. Quasi-solid-state electrolytes (QSSEs) are the most promising alternatives to commercial liquid electrolytes due to their high safety and great compatibility with electrodes. However, Li dendrite formation and the slow Li+ diffusion in QSSEs severely hinder uniform Li deposition, thus leading to Li dendrite growth and short circuits. Herein, an eco-friendly and low-cost sodium lignosulfonate (LSS)-assisted PVDF-based QSSE is proposed to induce uniform Li deposition and inhibit Li dendrite growth. Li symmetric cells with 5%-LSS QSSE possess a high Li+ transfer number of 0.79, and they exhibit a long cycle life of 1000 h at a current density/areal capacity of 1 mA cm−2/5 mAh cm−2. Moreover, due to the fast electrochemical dynamics endowed by the improved compatibility of the electrodes and fast Li+ diffusion, the LFP/5%-LSS/Li full cells still maintain a high capacity of 110 mAh g−1 after 250 cycles at 6C. This work provides a novel and promising choice that uses eco-friendly LSS as an additive to PVDF-based QSSE in Li metal batteries. [ABSTRACT FROM AUTHOR]

Ultrahigh hydrogen evolution from photocatalytic water splitting using CaTiO3 is difficult due to its low photon-to-electron conversion efficiency. Herein, a facile post-loading strategy was developed for preparing a RuS2@CaTiO3-x heterojunction by anchoring RuS2 on a multi-shelled hollow cube of CaTiO3, which successfully achieved ultrahigh hydrogen evolution through water splitting with the assistance of a photocatalytic biorefinery. After RuS2 anchoring, the utilization of visible light and the separation/migration rate of photo-generated carriers of RuS2@CaTiO3-x enhanced significantly, resulting in a high photon-to-electron conversion efficiency. Correspondingly, the hydrogen evolution rate reached 8140.7 μmol g−1 h−1 in the RuS2@CaTiO3-10 system with the assistance of the photocatalytic selective oxidation of biomass-derived monosaccharides, and it was 45.5- and 4.2-fold greater than those of pristine CaTiO3 and RuS2, respectively. Furthermore, 89.0% yield of lactic acid was obtained in the corresponding system. Electron spin-resonance (ESR) characterization combined with radical capture experiments indicated that ˙OH played a significant role in lactic acid production. Moreover, RuS2@CaTiO3-10 not only exhibits excellent reusability and stability, but also has been successfully used for different biomass-based monosaccharide reforming coupled with water-splitting to co-produce lactic acid and hydrogen. This work sheds light on the development and design of photocatalytic systems. [ABSTRACT FROM AUTHOR]

The selective photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water for co-producing chemicals and H2 is of great significance, but limited successes have been reported. In this study, a RuS2@CN-x photocatalyst with only exposed crystal face (200) was prepared by anchoring RuS2 nanoparticles on carbon nitride (CN) nanosheets and successfully used in photocatalytic C–C bond cleavage of biomass-based sugars coupling with water splitting to co-generate lactic acid and hydrogen. Interestingly, the RuS2 (200) crystal face combined with the interfacial synergism between CN and RuS2 in RuS2@CN-x effectively improved visible light absorption and enhanced the transfer/separation efficiency of photo-generated carriers. The RuS2@CN-2 exhibited superior photocatalytic activity towards synchronous water splitting and biomass conversion to co-produce hydrogen (8698.3 μmol g−1 h−1) and lactic acid (91.5%). Furthermore, the experimental and DFT calculation results indicated that the exposed crystal face (200) of RuS2 significantly enhanced the photocatalytic activity of RuS2@CN-2. Moreover, this reaction system not only has excellent recyclability but also displays excellent universality for small molecule biomass-derived monosaccharides and macromolecular xylan. This work provides a novel route to efficiently co-produce hydrogen and fine chemicals from photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water. [ABSTRACT FROM AUTHOR]

All‐solid‐state Li batteries (ASSLBs) with solid‐polymer electrolytes are considered promising battery systems to achieve improved safety and high energy density. However, Li dendrite formation at the Li anode under high charging current density/capacity has limited their development. To tackle the issue, Li‐metal alloying has been proposed as an alternative strategy to suppress Li dendrite growth in ASSLBs. One drawback of alloying is the relatively lower operating cell voltages, which will inevitably lower energy density compared to cells with pure Li anode. Herein, a Li‐rich Li13In3 alloy electrode (LiRLIA) is proposed, where the Li13In3 alloy scaffold guides Li nucleation and hinders Li dendrite formation. Meanwhile, the free Li can recover Li's potential and facilitate fast charge transfer kinetics to realize high‐energy‐density ASSLBs. Benefitting from the stronger adsorption energy and lower diffusion energy barrier of Li on a Li13In3 substrate, Li prefers to deposit in the 3D Li13In3 scaffold selectively. Therefore, the Li–Li symmetric cell constructed with LiRLIA can operate at a high current density/capacity of 5 mA cm−2/5 mAh cm−2 for almost 1000 h. [ABSTRACT FROM AUTHOR]

The efficient application of solar energy to realize photocatalytic biomass conversion to value-added chemicals is of significance. Herein, we propose a novel metal-free photocatalyst (4CzIPN@CMC-HG), which was prepared by encapsulating 1,2,3,5-tetrakis(carbazole-9-yl)-4,6-dicyanobenzene (4CzIPN) in a carboxymethylcellulose-based hydrogel (CMC-HG) using a one-step thermal polymerization strategy. 4CzIPN@CMC-HG has an efficient photon-to-electron conversion rate, excellent visible light absorption, fast photogenerated carrier migration/separation, and high photocatalytic activity, with 90.7% yield of lactic acid (LA) and 100.0% conversion of xylose due to the synergistic effects between 4CzIPN and CMC-HG. 4CzIPN@CMC-HG showed remarkable universality and excellent stability, and the 1000-times amplification system indicated that this system has a potential industrial application in LA production. Furthermore, trapping experiments indicated that ˙OH, h+, 1O2, and ˙O2− contributed to LA synthesis, with ˙O2− taking a leading role. These results showed the promising application prospects of metal-free photocatalysts in the photocatalytic biomass conversion to value-added chemicals. [ABSTRACT FROM AUTHOR]

Residual lignin plays an inhibitory role in the enzymatic hydrolysis of cellulosic biomass. In this study, we examined the structural changes in isolated lignins from the hot water hydrothermal pretreatment of aspen and their inhibitory effects on the enzymatic hydrolysis of Avicel. The functional groups of the isolated lignins were determined using quantitative 13C, 2D HSQC and 31P NMR. The increase in pretreatment severity significantly increased the condensed and non-condensed syringyl and guaiacyl OH group content in the isolated lignins, but decreased the aliphatic OH, p-hydroxybenzoate OH and carboxylic OH group content. A compelling adverse association (r2 = 0.998) was observed between the condensed syringyl and guaiacyl phenolic OH group content in lignins and their inhibitory effects on enzymatic hydrolysis. Langmuir adsorption isotherms showed that a higher pretreatment severity resulted in a higher binding ability between the isolated lignins and the cellulase enzymes, which led to more non-productive binding. It is hypothesized that condensed syringyl and guaiacyl phenolic units are mainly responsible for the inhibitory effect of lignin on enzymatic hydrolysis, in which the condensed aromatic rings enhance the hydrophobic interactions and the phenolic OH group boosts the hydrogen bonding. The combination of hydrophobic interactions and hydrogen bonding can further intensify undesirable non-productive binding. [ABSTRACT FROM AUTHOR]

A series of linoleic acid conjugated hydroxyethyl cellulose polymers (HEC- g -LA) were synthesized and characterized. And their solubilities in a variety of solvents were compared. The prepared HEC- g -LA polymers showed typical properties of amphiphilic polymers and were able to self-assemble into spherical nanomicelles in aqueous solution. The micelle sizes and critical micelle concentrations (CMC) were found correlated with the molecular structure of polymers, and were varied in the range of 20–50 nm and 1.92–21.76 μg/ml, respectively. Furthermore, the hydrophobic active component β-carotene (β-C) was successfully encapsulated into the HEC- g -LA micelles by sonication-dialysis method. The β-C encapsulation efficiency and loading content were found to be as high as 84.67% (w/w) and 4.23%. The results of in vitro release showed that the encapsulated β-C was continuously released from the micelles in phosphate buffered saline (PBS) medium for about 7 days. The self-assembled HEC- g -LA nanomicelles are potential nanocarriers of hydrophobic active compounds for functional food applications. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)/cellulose paper was prepared by adding aqueous dispersion of GO into cellulose fiber pulp in a traditional papermaking procedure. Cationic polyacrylamide (CPAM) was added as a mordant to induce the self-assembly of GO layers on the fiber surfaces. The surface morphology, mechanical properties and gas permeability of GO/cellulose paper with varying GO contents were investigated by scanning electron microscopy (SEM), tensile test, burst test, tear test and densometer. It was found that CPAM could prevent the self-aggregation of GO in fiber matrix and increase the loading efficiency of GO to up to 16 wt% without sacrificing the mechanical performances of the paper. This finding permitted the large scale preparation of GO/cellulose paper with high doping amount of GO, which exhibited dense and compact geometry and low gas permeability ideal for potential packaging applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • BP loading and rolling edge morphology were achieved in BP- s -CN synchronously. • Photocatalytic hydrogen evolution and biorefinery were achieved simultaneously. • Just 4.0 at% BP addition increases hydrogen yield by 4.8 times. • Ultra-high hydrogen evolution rate of 1.45 mmol h−1 was obtained by BP- s -CN. Photocatalytic biorefinery synchronously assisted hydrogen evolution is promising, but limited research has been implemented. Here, the biorefinery-assisted ultra-high hydrogen evolution photocatalyzed by black phosphorus sensitized carbon nitride (BP- s -CN) was achieved. The BP- s -CN was prepared by ultrasonic-assisted assembly and freeze-drying of a mixture of CN and 2D BP. It was proved that the interfacial interaction between 2D BP and CN significantly improves the visible light utilization of CN and accelerates the separation of photo-induced carrier. The BP- s -CN displays ultra-high hydrogen release rate of 1.45 mmol h−1 with the best lactic acid yield (74.4%). Just 4.0 at% BP addition increases hydrogen yield by 4.8 times. The BP- s -CN photocatalytic system is also applicable to different biomass-based monosaccharides, and pentoses were more appropriate to produce lactic acid than hexoses. Interestingly, among of h+, O 2 −, OH, and 1O 2 , the O 2 − played a major role for lactic acid production. [ABSTRACT FROM AUTHOR]

[Display omitted] • BP loading and rolling edge morphology were achieved in BP- s -CN synchronously. • Photocatalytic hydrogen evolution and biorefinery were achieved simultaneously. • Just 4.0 at% BP addition increases hydrogen yield by 4.8 times. • Ultra-high hydrogen evolution rate of 1.45 mmol h−1 was obtained by BP- s -CN. Photocatalytic biorefinery synchronously assisted hydrogen evolution is promising, but limited research has been implemented. Here, the biorefinery-assisted ultra-high hydrogen evolution photocatalyzed by black phosphorus sensitized carbon nitride (BP- s -CN) was achieved. The BP- s -CN was prepared by ultrasonic-assisted assembly and freeze-drying of a mixture of CN and 2D BP. It was proved that the interfacial interaction between 2D BP and CN significantly improves the visible light utilization of CN and accelerates the separation of photo-induced carrier. The BP- s -CN displays ultra-high hydrogen release rate of 1.45 mmol h−1 with the best lactic acid yield (74.4%). Just 4.0 at% BP addition increases hydrogen yield by 4.8 times. The BP- s -CN photocatalytic system is also applicable to different biomass-based monosaccharides, and pentoses were more appropriate to produce lactic acid than hexoses. Interestingly, among of h+, O 2 −, OH, and 1O 2 , the O 2 − played a major role for lactic acid production. [ABSTRACT FROM AUTHOR]

Activation of lignin by demethylation for improving the reactivity has attracted extensive attentions. However, it still faces many challenges, such as the unsatisfied increase of hydroxyl content and the undesired cracking of linear linkages. Here, the efficient demethylations for significantly increasing the hydroxyl content and protecting the structure of industrial lignin were explored using lewis acid as modification reagent. As BBr 3 was used, the phenolic hydroxyl content (Ar-OH) was increased by 80.65 %, but the lignin structure might be destroyed. About 75 % of the β- O -4 linkages could be fortunately retained by using AlCl 3. This method could also be used for the demethylation of alkaline poplar lignin with up to 171.67 % increase of Ar-OH (from 1.80 to 4.89 mmol/g). After activation, the antioxidant properties were improved 4.64-fold and 2.58-fold for 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, respectively. This work would provide a theory guidance for activation of lignin and facilitate its high-value application. • The phenolic hydroxyl content of the activated alkaline poplar lignin increases by 171.67 %. • The lignin activated by AlCl 3 retains most of its macromolecular structure. • The reaction time and the demethylation reagent are the key reasons for controlling the activation process. • The activated lignin shows significantly increased antioxidant properties for DPPH and ABTS+. [ABSTRACT FROM AUTHOR]

Simultaneous direct production of fuels and chemicals via photocatalytic biomass conversion is an effective strategy to achieve the carbon-neutral goal but no studies on the co-production of CO and xylonic acid have been reported. Here, an efficient CIS/GO@3D-OMA photocatalyst of CdIn2S4 (CIS) anchored on graphene oxide (GO) nanosheets in a three-dimensional ordered mesoporous aerogel was prepared and successfully used in the co-generation of CO and xylonic acid. Experimental results showed that CIS/GO@3D-OMA-3 has broad light absorption, high charge density, and fast charge space separation. Correspondingly, the CO and xylonic acid yield achieved 1213.88 μmol g−1 h−1 and 76.76% in the xylose system, respectively. Interestingly, the system is also applicable to xylan (CO: 187.20 μmol g−1 h−1; xylonic acid: 0.2 g gxylan−1). All h+, ˙OH, 1O2 and ˙O2− were conductive to CO and xylonic acid production, in which h+ played a primary role. This study provides a fresh perspective for biomass utilization. [ABSTRACT FROM AUTHOR]

[Display omitted] There is rapid progress in the field of 3D printing technology for the production of electrodes, electrolytes, and packages of batteries due to the technique's low cost, a wide range of geometries printable, and rapid prototyping speed by combining computer-aided design with advanced manufacturing procedures. The most important part of 3D printing applied in batteries is the printing of electrodes, electrolytes, and packages. These will affect the battery energy/power density. However, there are still several challenges that need to be overcome to print active and stable electrodes/electrolytes for energy storage systems that can rival that of the state-of-the-art. In this review, the printing materials, and methods for batteries from liquid to solid-state batteries are discussed and recent examples of this technique applied in high power/energy batteries are highlighted. This review for batteries will cover 3D printing technologies, printed cathode, and anode in conventional batteries, and printed solid-state electrolytes in solid-state batteries. The working principles, advantages, and limitations for solid-state batteries via the 3D printing method will be discussed before highlighting the printing materials for electrodes and electrolytes. We will then discuss how to modify the electrode and solid-state electrolyte to raise the electrochemical performance of solid-state batteries using 3D printing. Finally, we will give our insights into the future perspectives of this printing technique for fabricating batteries. [ABSTRACT FROM AUTHOR]

The application of photocatalysis in biomass reforming meets the needs of contemporary society for green and sustainable development, and its comprehensive utilization is appealing but challenging. Here, a novel metal-free photocatalyst (CQDs@4CzIPN) composed of carbon quantum dots (CQDs) anchored on 1,2,3,5-tetrakis(carbazole-9-yl)-4,6-dicyanobenzene (4CzIPN) was successfully prepared via a one-step hybrid evaporation–drying method. The sensitization of CQDs for 4CzIPN significantly broadened the absorption range of visible light by regulating the energy band structure, and also accelerated the migration/separation of photo-induced carriers. It is found that CQDs@4CzIPN exhibited excellent catalytic activity with a maximum lactic acid yield of 96.9%. CQDs@4CzIPN shows excellent stability and reusability in which the lactic acid yield retained 91.0% of its original value in the 5th cycle; meanwhile, this CQDs@4CzIPN system exhibited excellent universality for the photocatalytic conversion of biomass-derived monosaccharides to lactic acid, but interestingly, the activities of pentoses are significantly better than those of hexoses. Moreover, ·O2−, 1O2, h+ and ·OH were produced in the photocatalytic system, and their contents increased with visible light irradiation time. Oxidative active species capture experiments indicated that all of them are beneficial for lactic acid production, in which ·O2− plays a leading role. This work provides a green approach for biorefining, and will inspire researchers to develop metal-free photocatalysts and apply them to photocatalytic biomass conversion. [ABSTRACT FROM AUTHOR]

Conductive hydrogels have shown great promise in the field of sustainable power sources due to their unique features of sufficient flexibility, durability, and functional diversification. However, time‐ and energy‐consuming polymerization process and poor adaptability in extreme environments severely impede their practical application in such an emerging field. Herein, a facile and universal self‐catalytic system (AL‐Cu2+) based on alkali lignin (AL) macromolecule has been designed to rapidly fabricate conductive and transparent organohydrogels in alkaline water–ethylene glycol (EG) binary solvent, which displays extreme environment applicability (‒40 to 60 °C), eligible stretchability (≈800% elongation), and robust self‐adhesion (≈31.4 kPa). Interestingly, the introduced EG accelerates the polymerization, endows extreme freezing/drying resistance, and improves self‐adhesion for the organohydrogels. The organohydrogel (water/EG = 2/3) that combines the above merits inspires the construction of triboelectric nanogenerator (O‐TENG) for mechanical energy harvesting and converting regardless of low‐ or high‐temperature environments. The generated electricity by the O‐TENG can be used directly or stored to drive commercial electronics and installed on human joints for movement monitoring. This work sheds light on designing environment‐resistant flexible TENGs based on multifunctional soft materials with fast gelation strategy, provoking more attention to sustainable high‐value utilization of lignin for advanced applications. [ABSTRACT FROM AUTHOR]

The rational regulation of the structure of photocatalysts with an enhanced visible‐light absorption property and rapid charge dynamics is promising and challenging. Here, a facile method was developed for preparing oxygen‐doped carbon nitride bundles with porous hollow trunk‐shaped structures (Ox@CNB) using melamine with assistance of hydrochloric acid. Experimental results and density functional theory (DFT) calculations indicated that Ox@CNB exhibited controllable bandgaps (2.20–2.60 eV) and a low photoluminescence intensity. Interestingly, Ox@CNB displayed excellent photocatalytic activity for the synthesis of lactic acid (81.4 %) and universality for the reforming of biomass‐derived monosaccharides to lactic acid. The oxidation active species of h+, ⋅OH, ⋅O2− and 1O2 all promoted the lactic acid production, and h+ played a major role. A possible reaction mechanism of lactic acid synthesis was proposed by combining the experimental with the DFT results. A one‐thousand‐fold up‐scaled experiment demonstrated the significant application potential of the system for the industrial production of lactic acid. [ABSTRACT FROM AUTHOR]

The simultaneous production of hydrogen and biomass-based chemicals from biomass-derived feedstock aqueous solutions via photocatalysis is appealing because no additional sacrificial agent is needed. However, limited success has been achieved. This paper reports efficient nori-shaped carbon nitride-based photocatalysts with potassium/oxygen co-doping and cyano group introduction for efficient conversion of biomass-derived monosaccharides to produce lactic acid and hydrogen simultaneously. The obtained photocatalyst has an adjustable bandgap, fast migration/separation rate of photo-generated carriers and displays excellent photocatalytic performance with respect to xylose conversion (∼95.0%), lactic acid selectivity (90.5%) and hydrogen generation (∼33 380 μmol g−1 h−1) in the presence of visible light. The h+, ˙OH, ˙O2− and 1O2 drive xylose conversion and lactic acid production. For biomass-derived pentoses and hexoses, the reaction system also exhibits excellent photocatalytic activity of lactic acid selectivity and hydrogen generation; the reported photocatalyst has excellent reusability. This paper provides a new perspective for hydrogen generation and biorefineries via a photocatalyst. [ABSTRACT FROM AUTHOR]

Designing an ultra-light and controllable structure for multifunctionality of low-cost aerogels is of great significance but remains a huge challenge because of the limitations of structural processability and mechanical vulnerability. Herein, we demonstrated a facile approach to synthesize a low-cost, ultralight, elastic, and highly recyclable superabsorbent from renewable fibers via environmentally friendly physical bonding and freeze-drying. Our approach introduces skin-core structure polyester (SPFs) into natural agriculture plant kapok, through which fibers entanglement and bonding to construct aerogel with adjustable hierarchical structure and desirable shapes. The resultant composite aerogel can be easily modified by organosilane, demonstrating durable superhydrophobicity (158.5°), advanced absorption capacity (128.4 g/g), good mechanical performance, self-cleaning, and thermal insulating (0.020 W/(m·K)). Therefore, the sustainable and multifunctional composite fibrous porous aerogels are potential materials for oil absorption applications and thermal management. [Display omitted] • An multifunctionality and economical aerogel was achieved. • A porous structure was constructed via natural fibers entanglement and bonding. • The introduction of skin-core structure polyester resulted in a better formability. • The aerogel exhibited advanced absorption capacity and thermal insulation property. • Excellent reusability and sustainability of recycled aerogel. [ABSTRACT FROM AUTHOR]

S-scheme heterojunctions have become an emerging type of effective photocatalysts to convert biomass. However, there are few reports on the synergistic S-type heterojunction and oxygen vacancy enhanced photocatalytic biomass conversion. Here, an AgInS 2 @CeO 2 -x S-scheme heterojunction photocatalyst with abundant oxygen vacancies was developed through a simple thermal and mild annealing process, allowing for the simultaneous production of xylonic acid and CO. Under visible light, the xylonic acid yield and CO evolution rate reached 60.0% and 3689.9 μmol g−1 h−1, respectively, through the decomposition of xylose. It was found that the S-scheme staggered band structure could improve sunlight utilization, increase the reduction power of photogenerated electrons, and enhance the separation and transfer of photogenerated charge carriers. Furthermore, oxygen vacancies on the surface of CeO 2 for AgInS 2 @CeO 2 -x heterojunction can suppress the recombination of generated electrons and holes. This study offers a promising approach for designing artificial photosynthetic systems to promote photocatalytic biomass conversion. [Display omitted] • The AgInS 2 @CeO 2 -x S-scheme heterojunctions with enhanced CeO 2 oxygen defects were designed. • The synergism between S-scheme heterojunctions and oxygen vacancies accelerated charge separation of AgInS 2 @CeO 2 -x. • The CO evolution and xylonic acid yield reached 3689.9 μmol g−1 h−1 and 60.0%. • The yields of xylonic acid and CO via AgInS 2 @CeO 2 -20 were 1.39 and 1.44 times greater than AgInS 2. [ABSTRACT FROM AUTHOR]

Photocatalytic biorefinery integrated with CO 2 reduction to co-produce value-added chemicals and fuels is significant but challenging. Herein, a novel photocatalyst with dual active sites is constructed, in which Ru single atoms coordinated with N 2 O 2 on phosphorus-doped carbon nitride (Ru 1 N 2 O 2 @PCN x) via a pre-assembled pyrolysis strategy. Ru 1 N 2 O 2 @PCN 1.0 catalyst exhibits an exceptional performance in both CO 2 reduction and biorefinery processes, originating from the high photon-to-electron conversion rate. It achieves an extraordinary CO 2 reduction and biorefinery, with 100.1 μmol g−1 h−1 evolution of CO and 91.2% yield of lactic acid. Furthermore, the as-prepared Ru 1 N 2 O 2 @PCN 1.0 is successfully used in biomass-derived monosaccharides and xylan systems, validating the universality for broad applications. Experimental and theoretical analysis indicates that doping P in CN by replacing a corner C atom facilitates charge transfer/separation. Additionally, the introduction of Ru-N 2 O 2 coordination regulates the electronic structure of CN and reduces the reaction energy barrier. [Display omitted] • The dual active moieties of Ru-N 2 O 2 and P-N on CN nanosheets were designed. • Photocatalytic CO 2 reduction and biorefinery were achieved simultaneously. • CO evolution rate over Ru 1 N 2 O 2 @PCN x is 2.02 times higher than pure CN. • A high lactic acid yield of 91.2% was obtained over Ru 1 N 2 O 2 @PCN x. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design strategies and adsorption mechanisms of lignin-based adsorbent are reviewed. • The application of lignin-based adsorbents in wastewater is summarized. • Summarizing the regeneration and reuse of lignin-based adsorbents. • Future outlooks for lignin-based adsorbents are presented. The heavy metals, pesticides and dyes in agriculture and industry caused serious water pollution have increased the urgency for the advancement of biomass-based adsorbents due to their merits of low cost, high efficiency, and environmental sustainability. Thus, this review systematically examines the recent progress of lignin-based adsorbents dedicated to wastewater purification. Commencing with a succinct exposition on the intricate structure and prevalent forms of lignin, the review proceeds to expound rational design strategies tailored for lignin-based adsorbents coupled with adsorption mechanisms and regeneration methods. Emphasis is placed on the potential industrial applications of lignin-based adsorbents, accentuating their capacity for recovery and direct utilization post-use. The future challenges and outlooks associated with lignin-based adsorbents are discussed to provide novel perspectives for the development of high-performance and sustainable biosorbents, facilitating the effective removal of pollutants and the value-added utilization of resources in a sustainable manner. [ABSTRACT FROM AUTHOR]

Stretchable and tough hydrogels are highly required for various flexible devices. Liquid metal (LM) emerges as an attractive applicant in preparing functional hydrogels due to its unique features. However, the high fluidity of LM and incompatibility between LM and polymer matrix make it hard to fabricate tough hydrogels. Herein, inspired by the function of ligaments in biological structure, graphene oxide (GO) nanosheets are introduced to encapsulate LM droplets. GO nanosheets form strong interaction with both LM and polymer matrix to create a stable shell that prevents LM droplet from fracture and exudation to polymer network. The flexible LM/GO core–shell microstructure avoids phase separation and produces a tough hydrogel with stress of high up to 303 kPa at 1240% elongation. It also shows notch insensitivity and strong adhesion to various surfaces. This study opens the possibility of using LM in stretchable and tough hydrogels. [ABSTRACT FROM AUTHOR]

Pinoresinol structures, featuring a β-β′-linkage between lignin monomer units, are important in softwood lignins and in dicots and monocots, particularly those that are downregulated in syringyl-specific genes. Although readily detected by NMR spectroscopy, pinoresinol structures largely escaped detection by β-ether-cleaving degradation analyses presumably due to the presence of the linkages at the 5 positions, in 5-5′- or 5- O-4′-structures. In this study, which is aimed at helping better understand 5-linked pinoresinol structures by providing the required data for NMR characterization, new lignin model compounds were synthesized through biomimetic peroxidase-mediated oxidative coupling reactions between pre-formed (free-phenolic) coniferyl alcohol 5-5′- or 5- O-4′-linked dimers and a coniferyl alcohol monomer. It was found that such dimers containing free-phenolic coniferyl alcohol moieties can cross-couple with the coniferyl alcohol producing pinoresinol-containing trimers (and higher oligomers) in addition to other homo- and cross-coupled products. Eight new lignin model compounds were obtained and characterized by NMR spectroscopy, and one tentatively identified cross-coupled β -O-4′-product was formed from a coniferyl alcohol 5- O-4′-linked dimer. It was demonstrated that the 5-5′- and 5- O-4′-linked pinoresinol structures could be readily differentiated by using heteronuclear multiple-bond correlation (HMBC) NMR spectroscopy. With appropriate modification (etherification or acetylation) to the newly obtained model compounds, it would be possible to identify the 5-5′- or 5- O-4′-linked pinoresinol structures in softwood lignins by 2D HMBC NMR spectroscopic methods. Identification of the cross-coupled dibenzodioxocin from a coniferyl alcohol 5-5′-linked moiety suggested that thioacidolysis or derivatization followed by reductive cleavage (DFRC) could be used to detect and identify whether the coniferyl alcohol itself undergoes 5-5′-cross-linking during lignification. [ABSTRACT FROM AUTHOR]

Abstract: The Schiff''s bases of cellulose derivatives, o-pheylene diimido carboxymethyl cellulose (PDIMCMC) and p-sulfophenyl imodo carboxymethyl cellulose (SPIMCMC), were synthesized by the reaction of dialdehyde carboxymethyl cellulose (DACMC) with o-phenylene diamine (PDM) and p-aminobenzen sulfonic (ASA), respectively. Their structures were characterized by FTIR. The fluorescence spectra (FS) appeared and the Schiff''s bases had strong fluorescence intensities (FI). These FSs and FIs were influenced by either pH or solute concentration. For example the PDIMCMC results indicated that its FI reached maximum at pH=6.48 and its FS shifted to a longer wavelength in acidity; its FI is the strongest in 1.2×10−3 gmL−1. [Copyright &y& Elsevier]

Abstract: Chemical modification is the most important method to design novel biopolymer and biomaterials from the abundant and biocompatible hemicelluloses. In this paper, an efficient method to synthesize hemicellulosic derivatives with bifunctional groups was developed by the etherification of hemicelluloses with acrylamide in the butanol/water medium. Varying the reaction condition such as reaction time, reaction temperature, and the amount of acrylamide and so on, the optimized hemicellulosic derivative with a higher total degree of substituent (DS) of 0.92 and with the 0.43 ratio of carbamoylethy groups and carboxyethyl groups was obtained. 13C NMR analysis showed that the etherification occurred preferably at C-3 position of xylose. A significant degradation of the polymers occurred during the etherification. The shear-thinning of the hemicellulosic derivatives became more dramatic. The solution of the hemicellulosic derivatives showed lower viscosity and modulus as compared with the native hemicelluloses, exhibiting a less elastic behavior. [Copyright &y& Elsevier]

Abstract: Dewaxed wheat straw was treated with acetic acid–H2O (65/35, v/v), acetic acid–H2O (80/20, v/v), acetic acid–H2O (90/10, v/v), formic acid–acetic acid–H2O (20/60/20, v/v/v), formic acid–acetic acid–H2O (30/60/10, v/v/v), methanol–H2O (60/40, v/v) and ethanol–H2O (60/40, v/v) using 0.1% HCl as a catalyst at 85°C for 4h, in which 78.2, 80.0, 88.2, 89.4, 94.1, 23.5 and 37.4% of the original lignin, and 42.4, 58.7, 70.0, 65.1, 76.5, 14.2 and 22.2% of the original hemicelluloses was released, respectively. Lignins obtained were characterized by their content of hemicelluloses, composition of phenolic acids and aldehydes, molecular weight, thermal stability and by UV, Fourier transform infrared (FT-IR), 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The results showed that aqueous organic acid was more effective than aqueous organic alcohol for extensive delignification and selective fractionation of cellulose, lignin and hemicelluloses from the straw. In particular, the addition of formic acid gave a significant effect on the dissolution of lignin. All the acid-insoluble lignin fractions contained small amounts of contaminated hemicelluloses as shown by their content of neutral sugars, 0.9–4.3%, and had weight-average molecular weight between 3960 and 4340gmol−1. An increase in concentration of acetic acid or formic acid in organosolv resulted in an increment in release of guaiacyl units and in lignin condensation. However, the lignin preparations released during the treatment with aqueous organic alcohol without organic acid contained almost equal amounts of non-condensed guaiacyl and syringyl units with fewer p-hydroxyphenyl units. The β-O-4 ether bonds together with β-β, β-5 and 5-5′ carbon–carbon linkages were identified to be present in lignin substructures. [Copyright &y& Elsevier]

The selective oxidation of monosaccharides into sugar acids is an important reaction for the production of biomass-based chemicals, but the design of an efficient catalyst remains a big challenge. Herein we report a series of efficient and stable surface functionalized carbon nanotube supported palladium catalysts for the selective oxidation of monosaccharides into sugar acids at room temperature. The palladium nanoparticles supported on alkaline carbon nanotubes (Pd/CNT-N) showed the highest reaction activity. The maximum gluconic acid yield of 98.3% and xylonic acid yield of 95.8% were obtained at 30 °C within 180 min. DFT calculations revealed that the mechanism of xylose oxidation to xylonic acid involved the activation of OH−, adsorption of xylose, dissociation of the formyl C–H bond in xylose, formation of chemisorbed xylonic acid, and desorption of xylonic acid. The activation energy barrier for xylose oxidation over Pd/CNT-N is lower than that of Pd/CNT-O, explaining that the basic groups on CNT are more beneficial for accelerating monosaccharide oxidation and enhancing the sugar acid selectivity. This work not only presents a new facile route to produce sugar acid at room temperature, but also provides a basis to design and develop efficient catalysts with surface functionalized supports for various catalytic reactions. [ABSTRACT FROM AUTHOR]

Development of lignin-derived carbon adsorbents with ultrahigh phosphate adsorption activity and rapid adsorption kinetics is of great importance, yet limited success has been achieved. Herein, we develop a CeO 2 functionalized N-doped lignin-derived biochar (Ce@NLC) via a cooperative modification strategy for effective and fast phosphate capture. The novel modification strategy not only contributes greatly to the loading of well-dispersed CeO 2 nanoparticles with a smaller size, but also significantly increases the relative concentration of Ce(III) species on Ce@NLC. Consequently, an enhanced capture capacity for phosphate (196.85 mg g−1) as well as extremely rapid adsorption kinetics were achieved in a wide operating pH range (2–10). Interestingly, Ce@NLC exhibited a strong phosphate adsorption activity at even low-concentration phosphorus-containing water. The removal efficiency and final P concentration reached 99.87% and 2.59 μg P L−1 within 1 min at the phosphate concentration of 2 mg P L−1. Experiments and characterization indicated that Ce(III) species plays a predominant role for the phosphate capture, and ligand exchange, together with electrostatic attraction, are the main adsorption mechanism. This work develops not only an efficient carbon-based adsorbent for phosphate capture, but also promotes the high-value application of industrial lignin. Nitrogen-doped lignin-derived biochar with enriched loading of CeO 2 nanoparticles for highly efficient and rapid phosphate capture. [Display omitted] • Ce@NLC with smaller and Ce(III)-enriched CeO 2 nanoparticles is developed. • The maximum phosphate capture capacity of Ce@NLC reaches 196.85 mg g−1. • Ce@NLC exhibits a rapid phosphate capture in wide operating pH range (2–10). • Ce@NLC possesses strong adsorption activity at even a low phosphate concentration. [ABSTRACT FROM AUTHOR]

A rapid analytical procedure, which enables convenient quantitative determination of individual components in rice straw lipophilic extractives, has been developed in this study. The method comprises a Soxhlet extraction with toluene–ethanol (2 : 1, v/v), chloroform, petroleum ether, dichloromethane, or hexane, silylation, and gas chromatography on a medium-length capillary column. The chemical composition of five lipophilic extractives has been examined. Free fatty/resin acids, sterols, waxes, steryl esters, and triglycerides were identified as the major five classes of lipids. Over all the free fatty acids, the most abundant free fatty acids were palmitic acid (C16 : 0, 3.82–8.11%), linoleic acid (C18 : 2) and/or oleic acid (C18 : 1, 1.22–3.35%), hexadecenoic acid (C16 : 1, 1.36–2.96%), and heptadecanoic acid (C17 : 0, 0.86– 1.50%). β-Sitosterol and stigmasterol were the predominant components identified in a class of sterols, comprising over 90% of the total sterols. Palmitic acid palmity ester and palmitic acid oleyl ester were the major components analyzed in a group of waxes. The steryl esters identified were composed mainly of steryl palmitate, steryl oleate, steryl myristate, steryl heptadecanoate, and steryl laurate. Of the triglycerides identified, triolein was the dominant compound. Tripalmitin and dipalmitoyl-oleoylglycerol were also found in small amounts in this class of lipids. Diglycerides accounted for only minor amounts (0.19–0.33%) of the total extractives. [ABSTRACT FROM AUTHOR]

The photocatalytic selective oxidation of biomass-derived feedstocks to high-value organic acids is promising and challenging, especially for the production of xylonic acid. Herein, novel phosphorus-doped carbon nitride with grafted sulfonic acid groups (P@CN-SO3H) was prepared and successfully used in the photocatalytic-reforming of xylose to xylonic acid. The successful doping of phosphorus and grafting of sulfonic acid groups significantly extend the visible light adsorption range and decrease the photoluminescence intensity of the resulting carbon nitride, thereby enhancing its photocatalytic activity. P@CN-SO3H can efficiently catalyze the synthesis of xylonic acid (88.1%) from xylose with excellent stability and reusability. Electron spin-resonance results indicate that the contents of h+, ˙OH, ·O2−, and 1O2 increase with the irradiation time, facilitating the synthesis of xylonic acid, in which ˙O2− plays a primary role. The economic benefits and results of the present xylonic acid production system indicate its huge potential for industrial applications. [ABSTRACT FROM AUTHOR]

A simple and efficient photocatalytic method for the synthesis of dihydropyrimidinones (DHPMs) and their derivatives via porous ultrathin carbon nitride nanosheets (p-CNNs) without solvents was demonstrated. The yields of 3,4-dihydropyrimidin-2(1H)-ones/thiones and their derivatives were up to 97.0%. Furthermore, the yield of 5-ethoxycarbonyl-6-methyl-4-phenyl-3,4-dihydropyrimidin-2(1H)-one in the 10th cycle retained 98.9% of its 1st value. Considering the environmental and economic benefits, this work exhibits various merits including excellent yields, environmental friendliness, inexpensiveness, and avoiding the use of solvents and metal-based photocatalysts. In addition, the excellent performance of the p-CNNs and environmentally benign reaction system have also been checked by the photocatalytic synthesis of 12-phenyl-9,9-dimethyl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one and 5-phenyl-1(4-methoxyphenyl)-3[(4-methoxy-phenyl)-aminol]-1H-pyrrol-2(5H)-one. This work paves a new way for carrying out a three-component reaction using metal-free photocatalysts under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The utilization of photocatalysis for the simultaneous production of valuable fine chemicals and fuels from biomass-derived feedstocks holds significant promise; however, its practical implementation remains constrained. In this study, we present the development of an Fe-doped gallium nitride (GaN) catalyst treated by calcination (Fe@GaN-X) for the selectively conversion of biomass-based monosaccharides and xylan into lactic acid and carbon monoxide (CO). Fe@GaN-400 exhibited broader visible light absorption, lower resistance, and reduced photoluminescence intensity in comparison to pristine GaN, thereby affording exceptional photocatalytic activity (lactic acid yield: 71.38%; CO evolution rate: 385.74 μmol g−1 h−1). When monosaccharides and xylan were used as substrates, the Fe@GaN-400 system demonstrated outstanding photocatalytic activity, particularly in the case of xylan system (CO evolution rate = 923.21 μmol g−1 h−1). Additionally, the experimental results revealed the generation of distinctive reactive species, encompassing holes (h+), superoxide anion (·O 2 -), hydroxyl radical (·OH) and singlet oxygen (1O 2) within this catalytic system. Remarkably, the ·O 2 - and h+ exhibit heightened selectivity towards CO and lactic acid, respectively. This work establishes a novel pathway for the co-production of fine chemicals and fuels through the photocatalytic conversion of biomass. [Display omitted] • A Fe-doped GaN photocatalyst was successfully developed by calcination treatment. • Up to 71.38% of lactic acid and 385.74 μmol g−1 h−1 of CO were co-produced. • Fe@GaN-400 demonstrated excellent universality for monosaccharides and xylan. • ·O 2 - and h+ exhibited the highest selectivity for CO and lactic acid, respectively. [ABSTRACT FROM AUTHOR]