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Animal genotyping by means of genome-wide association studies is important for connecting phenotypes of interest with their underlying genetics in livestock. However, the use of whole genome sequencing to investigate chest circumference (CC) in donkeys has rarely been reported. We aimed to use the genome-wide association study approach to detect significant single nucleotide polymorphisms (SNPs) and key genes associated with chest circumference traits in Xinjiang donkeys. We assessed 112 Xinjiang donkeys in this study. The chest circumference of each was measured 2 h before milking. We re-sequenced blood samples from the Xinjiang donkeys, and genome-wide association study analyses were performed using a mixed model with the PLINK, GEMMA, and REGENIE programs. We tested 38 donkeys for candidate SNPs for genome-wide association study using three software programs. Additionally, 18 SNP markers reached genome-wide significance (p < 1.61 × 10−9). On the basis of these, 41 genes were identified. Previously proposed candidate genes for CC traits were supported by this study, including NFATC2 (Nuclear Factor of Activated T Cells 2), PROP1 (PROP Paired-Like Homeobox 1), UBB (Ubiquitin B), and HAND2 (Heart and Neural Crest Derivatives Expressed 2). These promising candidates provide a valuable resource for validating potential meat production genes and will facilitate the development of high-yielding Xinjiang donkey breeds through marker-assisted selection or gene editing.

Using renewable biomass to replace fossil resources for producing low-carbon-footprint but high-value chemicals is a sustainable approach to pursue a carbon-neutral society. Herein, a boron nitrogen doped carbon (BNC) confined Pd single atom catalyst (Pd SAs/BNC) is synthesized and used as a robust catalyst toward the reductive amination reaction to produce low-carbon-footprint amines from renewable biomass. Because of the finely tuned electron structure, the as-synthesized single atom catalyst delivers an ultrahigh turn-over frequency value (max. 1368 h− 1) in the reductive amination of aldehydes/ketones and demonstrates a great conversion capacity for various aldehyde/ketone and amine/nitro-compound substrates. Extensive characterizations and density functional theory calculations show that the highly polar metal-N site formed between the central Pd single atom and its neighboring N and B atoms favors hydrogen activation from the donor (reductants) and hydrogen transformation to the receptor (C = O group), resulting in a great selectivity. This system could be further extended to directly produce various aromatic and furonic amines from renewable lignocellulosic biomass, and their greenhouse gas emission potentials are negative compared to those of fossil-fuel resource-based amines. This work offers a highly efficient and sustainable approach to construct C-N bonds for the production of numerous amines from carbon-neutral biomass resources.

The aim of this study was to investigate the selection signatures at a genome-wide level in 'Pishan' sheep using Specific Locus Amplified Fragment (SLAF)-seq. Blood samples from 126 ewes were sequenced using SLAF tags, and the ovarian tissues from 8 ewes (Bashbay sheep, a single litter size group (SG group); 'Pishan' sheep, double litter size group (DG group)) were collected to detect expression levels by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Selection signature analysis was performed using global fixation index (Fst) and nucleotide diversity (π) ratio. A total of 1,192,168 high-quality SLAFs were identified. Notably, 2380 candidate regions under selection using two approaches were identified. A total of 2069 genes were identified, which were involved in dopaminergic synapses, thyroid hormone synthesis, ovarian steroidogenesis and thyroid hormone signalling pathways. Furthermore, Growth Differentiation Factor 9 (

The conversion of lignocellulosic biomass waste into fuels and chemicals can be regarded as a carbon-neutral circular framework, which is particularly appealing for our sustainable society. In this...

Heterogeneous electro-Fenton is an efficient advanced oxidation process for the degradation of refractory organic contaminants in wastewater, and its efficiency is governed by cathodic catalysts. I...

Heterogeneous Electro-Fenton (EF) enables rapid elimination of recalcitrant organic pollutants without producing undesirable byproducts, but stable functioning of this process remains challenging. ...

Glucose electrolysis offers a prospect of value-added glucaric acid synthesis and energy-saving hydrogen production from the biomass-based platform molecules. Here we report that nanostructured NiFe oxide (NiFeOx) and nitride (NiFeNx) catalysts, synthesized from NiFe layered double hydroxide nanosheet arrays on three-dimensional Ni foams, demonstrate a high activity and selectivity towards anodic glucose oxidation. The electrolytic cell assembled with these two catalysts can deliver 100 mA cm−2 at 1.39 V. A faradaic efficiency of 87% and glucaric acid yield of 83% are obtained from the glucose electrolysis, which takes place via a guluronic acid pathway evidenced by in-situ infrared spectroscopy. A rigorous process model combined with a techno-economic analysis shows that the electrochemical reduction of glucose produces glucaric acid at a 54% lower cost than the current chemical approach. This work suggests that glucose electrolysis is an energy-saving and cost-effective approach for H2 production and biomass valorization. Renewable biomass conversion may afford high-value products from common materials, but catalysts usually require expensive metals and exhibit poor selectivities. Here, authors employ nickel-iron oxide and nitride electrocatalysts to produce H2 and to convert glucose to glucaric acid selectively.

Nanobiochar has received much attention recently among engineered biochar types owing to its useful chemical and physical properties. Research efforts have attempted to discover novel methods for nanobiochar preparation and applications. In this review, we summarize the literature on various aspects of nanobiochar preparation, production and use. Often, the bulk parent biochar is obtained from biomass pyrolysis, and mechanically ground using different milling processes to fabricate nanobiochar. Apart from mechanical means, direct fabrication of nanobiochar through flash heating resulting in graphitic nanosheets has been reported. Process conditions applied to the parent biochar directly influence the properties of the resulting nanobiochar. For instance, over 70% of 33 nanobiochar samples derived from biomass pyrolyzed above 450 °C demonstrated 32 times greater BET specific surface areas than nanobiochar produced at

Carbon-based materials are recognized as promising candidates for pollutant degradation because of their environmental benignity. Massive and cost-effective production and efficient recovery of carbon-based catalysts are crucial to apply this technology. However, various nanostructured carbons with different dimensions are usually utilized as precursors while not considering their complex preparation procedures and the high costs of ingredients. Moreover, catalyst separation and recovery are not given sufficient attention. In this work, a calcium salt-assisted pyrolysis strategy is proposed to tune the catalytic site formation of carbon-based catalysts. Results show that blending equal amounts of Ca

Activation of peroxymonosulfate (PMS) to degrade recalcitrant organic pollutants has attracted much attention, however, this process usually needs expensive or toxic catalysts. Herein, we prepared a Fe functionalized biochar composite that contain Fe0, porous carbon with abundant functional groups and nanofibers (Fe-BC-700) to activate PMS and efficiently remove bisphenol A (BPA). The contribution of different participants in the complicated system involving Fe species, carbon composites, and radicals and nonradicals were quantitatively investigated. Under optimal conditions (0.2 g/L PMS and 0.15 g/L catalyst), 20 mg/L of BPA can be completely removed in 5 min by Fe-BC-700. The effects including the activation of PMS by Fe species to produce sulfate radicals (SO4 −), the electron transfer by the nanofiber-mesoporous carbon structure, and the inherent persistent free radicals (PFR) in biochar, were demonstrated to contribute to the high performance. A series of contrast experiments showed that PMS activated by Fe contributed to about 36% of BPA degradation, while the carbon composites, especially carbon nanofibers contributed to 17%, and the other 47% was ascribed to the adsorption of carbon composites (may further undergoing degradation). Meanwhile, the degradation by SO4 − accounted for about 23% (by quenching experiments), while the nonradical pathway contributed to 30%. This work suggests that the non-activation factors in PMS/porous catalyst/pollutant system cannot be neglected.

Global warming, environmental pollution, and an energy shortage in the current fossil fuel society may cause a severe ecological crisis. Storage and conversion of renewable, dispersive and non-perennial energy from the sun, wind, geothermal sources, water, or biomass could be a promising option to relieve this crisis. Carbon materials could be the most versatile platform materials applied in the field of modern energy storage and conversion. Conventional carbon materials produced from coal and petrochemical products are usually energy intensive or involve harsh synthetic conditions. It is highly desired to develop effective methods to produce carbon materials from renewable resources that have high performance and limited environmental impacts. In this regard, biochar, a bio-carbon with abundant surface functional groups and easily tuned porosity produced from biomass, may be a promising candidate as a sustainable carbon material. Recent studies have demonstrated that biochar-based materials show great application potential in energy storage and conversion because of their easily tuned surface chemistry and porosity. In this review, recent advances in the applications of biochar-based materials in various energy storage and conversion fields, including hydrogen storage and production, oxygen electrocatalysts, emerging fuel cell technology, supercapacitors, and lithium/sodium ion batteries, are summarized, highlighting the mechanisms and open questions in current energy applications. Finally, contemporary challenges and perspectives on how biochar-based materials will develop and, in particular, the fields in which the use of biochar-based materials could be expanded are discussed throughout the review. This review demonstrates significant potential for energy applications of biochar-based materials, and it is expected to inspire new discoveries to promote practical applications of biochar-based materials in more energy storage and conversion fields.

Value-added materials such as biochar and activated carbon that are produced using thermo-chemical conversion of organic waste have gained an emerging interest for the application in the fields of energy and environment because of their low cost and unique physico-chemical properties. Organic waste-derived materials have multifunctional abilities in the field of environment for capturing greenhouse gases and remediation of contaminated soil and water as well as in the field of energy storage and conversion. This review critically evaluates and discusses the current thermo-chemical approaches for upgrading organic waste to value-added carbon materials, performance enhancement of these materials via activation and/or surface modification, and recent research findings related to energy and environmental applications. Moreover, this review provides detailed guidelines for preparing high-performance organic waste-derived materials and insights for their potential applications. Key challenges associated with the sustainable management of organic waste for ecological and socio-economic benefits and potential solutions are also discussed.

Exosomes are a subset of nano-sized extracellular vesicles originating from endosomes. Exosomes mediate cell-to-cell communication with their cargos, which includes mRNAs, miRNAs, lncRNAs, and circRNAs. Exosomal RNAs have cell specificity and reflect the conditions of their donor cells. Notably, their detection in biofluids can be used as a diagnostic marker for various diseases. Exosomal RNAs are ideal biomarkers because their surrounding membranes confer stability and they are detectable in almost all biofluids, which helps to reduce trauma and avoid invasive examinations. However, knowledge of exosomal biomarkers remains scarce. The present review summarizes the biogenesis, secretion, and uptake of exosomes, the current researches exploring exosomal mRNAs, miRNAs, lncRNAs, and circRNAs as potential biomarkers for the diagnosis of human diseases, as well as recent techniques of exosome isolation.

In this study, the catalytic activity and stability of Pd nanoparticles during the reduction of 4-nitrophenol (4-NP) were significantly enhanced by the interaction of Fe3O4/biochar support prepared by pyrolysis of fir sawdust. Compared with the commercial Pd/C with 5% of Pd content, the as-synthesized Pd@Fe3O4/biochar with only 1.58% of Pd content exhibited twice higher catalytic performance toward the 4-NP reduction. The significant enhancement of catalytic activity was ascribed to the interaction between Fe and Pd NPs which lowers the binding energy of Pd on surface of Pd@Fe3O4/biochar, resulting the fast desorption of the intermediate species during the reaction. Furthermore, the carbon skeleton expedites the electron transfer and facilitates the formation of active hydrogen and deprotonation of 4-NP which are key steps of reduction of 4-NP. The abundant oxygen containing groups in biochar may act as pinchers to tightly fix the Pd NPs and improve the stability of Pd@Fe3O4/biochar.

Platinum (Pt) based materials are widely used in electrocatalytic oxygen reduction reaction (ORR) with excellent catalytic activity, but its low abundance and expensive nature impede the broaden application. Alloying Pt with 3d transition metals is a good choice to reduce the Pt content but not decrease its ORR activity. Herein, a nitrogen-doped carbon stabilized Pt–Co bimetallic nanoparticles (Pt–Co/NC) with very low Pt content (0.51 wt %) was facilely synthesized through a metal–organic framwork (MOF) templated approach. The as-synthesized Pt–Co/NC shows favorable ORR catalytic activity with 0.87 V of half-wave potential, higher than many benchmark 20% Pt/C and a lot of previouely reported Pt containing ORR catalysts with high Pt content. Particularly, unlike conventional Pt based ORR catalysts, the Pt–Co/NC presents favorable methanol tolerance. This work provides a new method to prepare cost-effective and multifunctional catalysts using N-containing MOF template.

Searching efficient sustainable approaches for the metal nanoparticles (NPs) synthesis has become a research focus. Bioreduction with metal-reducing bacterium at ambient temperature provides a green route for metal NPs synthesis, especially for precious metals. In this work, activated Pd NPs were synthesized by contacting Pd2+ solution with an efficient metal-reducing Shewanella oneidensis bacterium, in which the bacterium acted as reducing, capping, and stabilizing agents, and the shape and composition of the Pd NPs could be tuned with the activation of KOH at elevated temperatures. The as-activated Pd NPs showed a favorable performance toward catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP), with a remarkable apparent kinetic constant of 5.0 × 10–3 s–1, which was 12 times greater than that of the raw biogenic Pd NPs, even comparable to that of the commercial 5.0 wt % Pd/C. Changes of the Pd NPs aggregates, ratio of Pd to S, and surface area of the support at different temperatures and...

The large scale lignocellulosic biomass wastes could also be regarded as abundantly-available renewable resources, and how to convert them into value-added products via sustainable approaches is still a big challenge. In this work, we demonstrated a facile pyrolysis method to construct N, P-dually doped biochar materials from the lignocellulosic biomass wastes. The as-synthesized N, P-dually doped biochar samples could act as electrocatalysts for oxygen reduction and evolution reactions (ORR/OER), showing excellent catalytic performance and long-term durability, as well as robust tolerance to CO and methanol. The unique hierarchical porous structure, favorable electronic structure modified by the N and P doping, as well as a variety of defect sites induced by the N and P doping into the carbon framework were identified as the main contributions to the prominent catalytic activity of the as-synthesized N, P-dually doped biochar materials. We expect this work would spur more efforts into developing advanced materials from the large scale lignocellulosic biomass wastes.

Microalgae, with robust nutrition intake capacity and rapid growth rate, could enrich large amounts of nutrition elements (N and P) and CO2 from the environment, providing an effective way to counter water eutrophication and global warming. However, how to effectively dispose the massive biomass rich in carbon and nutrition contents is still a big challenge. In this work, the microalgae biomass was used as a precursor to synthesize the N-enriching porous carbon materials via a facile pyrolysis method. The as-synthesized materials exhibited robust electrocatalytic oxygen reduction reaction (ORR) activities in both alkaline and acidic media, showing a superb catalytic ORR activity (high catalytic activity, favorable durability, as well as excellent tolerance to methanol and CO). Large surface area with mesopore structure, as well as abundant active nitrogen sites were mainly responsible for their robust electrocatalytic performance. The pyridinic N species was identified as the ORR catalytic site, and its contribution was quantitatively analyzed. The performance of the as-assembled Zn-air battery equipped with the as-synthesized N-enriching carbon materials for air cathode catalyst further confirms its superb effectiveness for ORR. The results provided in this work would provide a sustainable and cost-effective method to produce high-performance carbon materials for energy storage and conversion from the large-scale biomass wastes.

Lead (Pb) pollution in natural water bodies is an environmental concern due to toxic effects on aquatic ecosystems and human health, while adsorption is an effective approach to remove Pb from the water. Surface interactions between adsorbents and adsorbates play a dominant role in the adsorption process, and properly engineering a material’s surface property is critical to the improvement of adsorption performance. In this study, the magnesium oxide (MgO) nanoparticles stabilized on the N-doped biochar (MgO@N-biochar) were synthesized by one-pot fast pyrolysis of an MgCl2-loaded N-enriched hydrophyte biomass as a way to increase the exchangeable ions and N-containing functional groups and facilitate the adsorption of Pb2+. The as-synthesized MgO@N-biochar has a high performance with Pb in an aqueous solution with a large adsorption capacity (893 mg/g), a very short equilibrium time (

Biomass is increasingly perceived as a renewable resource rather than as an organic solid waste today, as it can be converted to various chemicals, biofuels, and solid biochar using modern processes. In the past few years, pyrolysis has attracted growing interest as a promising versatile platform to convert biomass into valuable resources. However, an efficient and selective conversion process is still difficult to be realized due to the complex nature of biomass, which usually makes the products complicated. Furthermore, various contaminants and inorganic elements (e.g., heavy metals, nitrogen, phosphorus, sulfur, and chlorine) embodied in biomass may be transferred into pyrolysis products or released into the environment, arousing environmental pollution concerns. Understanding their behaviors in biomass pyrolysis is essential to optimizing the pyrolysis process for efficient resource recovery and less environmental pollution. However, there is no comprehensive review so far about the fates of chemical elements in biomass during its pyrolysis. Here, we provide a critical review about the fates of main chemical elements (C, H, O, N, P, Cl, S, and metals) in biomass during its pyrolysis. We overview the research advances about the emission, transformation, and distribution of elements in biomass pyrolysis, discuss the present challenges for resource-oriented conversion and pollution abatement, highlight the importance and significance of understanding the fate of elements during pyrolysis, and outlook the future development directions for process control. The review provides useful information for developing sustainable biomass pyrolysis processes with an improved efficiency and selectivity as well as minimized environmental impacts, and encourages more research efforts from the scientific communities of chemistry, the environment, and energy.

Biochar is a solid material obtained from thermochemical conversion of biomass in an oxygen-limited environment. It is widely used as a soil remediator and carbon sequestrator. However, its biotoxicity to the ecosystem remains unclear. In this study, we assess the toxic effects of three fast pyrolytic biochar extract solutions (rice husk, saw dust, Acorus calamus) on a miocroorganism (Pseudomonas aeruginosa), a plant (Triticum spp.), and an animal (Caenorhabditis elegans). Systematic toxicity tests indicate that the biotoxicity of biochars varies with their biomass sources. Biochars derived from rice husk and sawdust have negligible toxic effects on all the tested organisms, suggesting that biochars obtained from agricultural waste are safe for soil application. By contrast, biochar derived from Acorus calamus shows significant toxicity on all tested organisms at relative high dosage, indicating that risk assessment is necessary before its environmental use. Furthermore, this study found that use of the U...

Glucose electrolysis offers a prospect of value-added glucaric acid synthesis and energy-saving hydrogen production from the biomass-based platform molecules. Here we report that nanostructured NiFe oxide (NiFeOx) and nitride (NiFeNx) catalysts, synthesized from NiFe layered double hydroxide nanosheet arrays on three-dimensional Ni foams, demonstrate a high activity and selectivity towards anodic glucose oxidation. The electrolytic cell assembled with these two catalysts can deliver 100 mA cm−2 at 1.39 V. A faradaic efficiency of 87% and glucaric acid yield of 83% are obtained from the glucose electrolysis, which takes place via a guluronic acid pathway evidenced by in-situ infrared spectroscopy. A rigorous process model combined with a techno-economic analysis shows that the electrochemical reduction of glucose produces glucaric acid at a 54% lower cost than the current chemical approach. This work suggests that glucose electrolysis is an energy-saving and cost-effective approach for H2 production and biomass valorization., Renewable biomass conversion may afford high-value products from common materials, but catalysts usually require expensive metals and exhibit poor selectivities. Here, authors employ nickel-iron oxide and nitride electrocatalysts to produce H2 and to convert glucose to glucaric acid selectively.

The oily sludge is a category of hazardous solid waste generated in petrochemical industries. Pyrolysis is an efficient approach for sustainable treating the oily sludge with limited environmental impacts, but the pollutant emission during the pyrolysis process is still a big challenge. Herein, the emission characteristics of nitrogen (N) and sulfur (S) containing pollutants during the oily sludge pyrolysis with and without catalysis was illuminated via a TG-FTIR-MS system (ThermoGravimetric-Fourier Transform InfaRed-Mass Spectroscopy). The FeMg layer double hydroxide (FeMg LDH) was employed as a catalyst for pyrolysis. The emission characteristics of six inorganic N-/S-containing pollutants, as well as ten organic N- and nine S-containing pollutants were analyzed. The results indicate that the FeMg LDH could efficiently suppress the emission of N-/S-containing pollutants. The amide and heterocyclic-N species were identified as primary resources of N-containing pollutants emission. The aliphatic- and disulfides-S were the main contributions to the S-pollutants emission. Comprehensive analysis of pollutants emission characteristics for oily sludge pyrolysis could provide a better understanding for sustainable managements of the hazardous solid wastes.

Massively produced sewage sludge brings a serious problem to environment. Pyrolysis is a promising and bifunctional technology to dispose the sewage sludge and recover energy, in which a large amount of pyrolytic sludge char is also produced. In this study, we proposed a value-added utilization of sludge char. We prepared an adsorbent with ultrahigh capacity for hydrophobic organic pollutant (1-naphthol) by pyrolysis of sludge and removal of the ash moiety from the sludge char. The adsorptive behavior of the adsorbent is strongly dependent on the pyrolytic temperature of sludge, and the maximum adsorption capacity of 666 mg g(-1) was achieved at 800 °C, which is comparable to deliberately modified graphene. Further exploration indicated that the robust adsorption to 1-naphthol is attributed to the catalytic effect of ash in sludge which facilitated the formation of more orderly graphitic structures and aromaticity at high pyrolytic temperatures.

Controllable integration of metallic nanoparticles and metal–organic frameworks (MOFs) may create a new material with multifunctional applications. In this work, an emerging type of core–shell nanostructure, in which metallic Pd nanoparticle cores were encapsulated by MOF (ZIF-67) shells, was facilely synthesized through an impregnation–reduction process. The as-synthesized Pd@ZIF-67 material, with highly dispersed Pd nanoparticles encapsulated in the porous ZIF-67 structure, exhibited favorable catalytic performance towards the formic acid (HCOOH)-induced reduction of highly toxic hexavalent chromium (Cr(VI)). In this process Cr(VI) was converted to Cr(III) within 5 min, and the material could be reused 10 times without significant loss of its catalytic activity. The highly hydrophilic and swellable nature of the ZIF-67 was proposed to be responsible mainly for the favorable durability of the Pd@ZIF-67. The results provided in this work may pave a way for the concise preparation of nano-hybrid catalysts with high performance and durability for pollutant elimination.

The production of phenol in high yield and selectivity by direct catalytic hydroxylation of benzene (HOB) is challenging. In this study, a carbon supported bimetallic Cu–Ag NPs composite was synthesized (Cu–Ag/C) via one-pot fast pyrolysis of Cu–Ag preloaded sawdust. Characterization of the product using various techniques illustrated that Cu and Ag NPs were monodispersed on the biochar, which were obtained during the fast pyrolysis of biomass. The as-synthesized Cu–Ag/C efficiently catalyzed the HOB reaction, resulting in the production of phenol. The maximum yield of phenol was 34.9%, whereas the selectivity for phenol was 96% at 50 °C. The experimental results using various solvents at different retention times incorporated with GC/MS, ESR, and H2-TPD determinations suggested that ˙OH radicals played a dominant role in the catalytic HOB reaction, where Cu and Ag offered a synergistic interaction. This study may provide a new avenue for the preparation of catalysts and offer insight into the synergistic interaction of bimetallic catalytic HOB reactions.

Lead (Pb) is one of the most widespread toxic heavy metals in water distribution systems and surface water, and how to quickly and completely remove Pb from the water has received global concern. Here we designed and synthesized a 3D nitrogen doped carbon hydrogel/FeMg layered double hydroxide (NC–FeMg LDH) nanocomposite through a one-pot solvothermal process and investigated the Pb removal efficiency and underlying mechanism. Multiple characterization methods including XRD, FTIR, and TEM confirmed that the 3D NC–FeMg LDH is formed by incorporating 2D FeMg-LDH nanosheets with the nitrogen doped carbon hydrogel which is in situ formed in the solvothermal carbonization of glucosamine. The as-synthesized 3D NC–FeMg LDH shows favorable performance in the removal of Pb from aqueous solution with very short equilibrium time (2 min) and large adsorption capacity (344.8 mg g−1). The excellent removal performance toward Pb is demonstrated to be a structure-dependent multiplex surface chemical process between Pb and LDH involving Mg2+/Pb2+ ion exchange, Pb/CO or OC–O, and Pb/pyrrolic N surface complexation. This work may provide an idea for designing hybrid functional materials for selective and high-efficiency removal of other heavy metals from polluted water.

Disposal of heavy metal-contaminated biomass obtained from phytoremediation or biosorption by using environmentally benign methods is a big challenge. In this study, we proposed a win–win strategy to recycle Ag-contaminated biomass by fast pyrolysis to obtain renewable bio-oil and achieve the catalytic reduction of Cr(VI) with the Ag-embedded biochar. We herein focused on the one-pot synthesis of a Ag nanoparticle-embedded biochar hybrid material (Ag@biochar) by fast pyrolysis of the Ag preloaded biomass and its catalytic effect on Cr(VI) reduction. The results show that Ag@biochar can completely catalytically reduce Cr(VI) in aqueous solution within 20 min using formic acid as a reducing agent at 323 K. The particle size of Ag NPs on the biochar was found to be pyrolysis temperature dependent and played an important role in the reduction of Cr(VI). We found that the reduction of Cr(VI) catalyzed by Ag@biochar follows a CO (produced from HCOOH decomposition) reduction mechanism which is quite different from the H2 reduction mechanism with catalysis of some noble metal based catalysts (e.g. Pd and Pt). This study offers a sustainable approach for simultaneous disposal of the biomass waste and synthesis of functional materials and might be expanded in the recycling of other metal-contaminated biomass (e.g. Cu, Ni, Co, Zn, and Fe).

The oxygen reduction reaction (ORR) is critical to various energy conversion and storage systems. Developing cost-effective and high performance metal-free carbon as an alternative to Pt-based ORR electrocatalytsts is a promising strategy for the commercialization of these clean energy conversion technologies. In this work, the microalgae biomass with a high N content was used as a precursor to prepare N-doped biochar material via an ionic liquid-assisted carbonization process. Experimental results show that the sp2/sp3 carbon interface and pore structure of the as-synthesized biochar material could be tuned by the polymerization of the ionic liquids and the catalysis of Fe species in the carbonization process. The as-synthesized N-doped biochar material exhibited robust electrocatalytic ORR performance with a high catalytic activity, excellent long-term stability and great tolerance to methanol and CO. The pyridinic N species was identified as the active catalytic site for the ORR. A Zn-air battery was assembled using the N-doped biochar as the air cathode catalyst and showed favourable performance. This work provides a straightforward strategy to prepare efficient and low-cost functional carbon materials for clean energy conversion from naturally abundant biomass.

In this work, we have found that a new Fe-N module, FexN (x = 2, 3, or 4), in which the N atoms insert the lattice of Fe matrix, also has high catalytic activity towards ORR. We synthesized the FexN module embedded N-doped carbon material (FexN/NC) via a facile metal-organic framework (MOF)-templated approach. The as-synthesized FexN/NC shows a superb catalytic ORR activity as well as high methanol tolerance. The highly efficient catalytic active sites (FexN module and well-doped N species) were mainly responsible for the superb ORR activity. The synergistic mechanisms of the N-doped carbon support and FexN moieties for ORR at molecular level were elucidated by density functional theory calculations. The excellent catalytic ORR performance make the FexN/NC catalyst be a promising candidate to replace the expensive Pt based cathodic catalyst in Zn-air batteries.

The oxygen evolution reaction (OER) catalytic activity of a transition metal oxides/hydroxides based electrocatalyst is related to its pseudocapacitance at potentials lower than the OER standard potential. Thus, a well-defined pseudocapacitance could be a great supplement to boost OER. Herein, a highly pseudocapacitive Ni-Fe-Co hydroxides/N-doped carbon nanoplates (NiCoFe-NC)-based electrocatalyst is synthesized using a facile one-pot solvothermal approach. The NiCoFe-NC has a great pseudocapacitive performance with 1849 F g-1 specific capacitance and 31.5 Wh kg-1 energy density. This material also exhibits an excellent OER catalytic activity comparable to the benchmark RuO2 catalysts (an initiating overpotential of 160 mV and delivering 10 mA cm-2 current density at 250 mV, with a Tafel slope of 31 mV dec-1 ). The catalytic performance of the optimized NiCoFe-NC catalyst could keep 24 h. X-ray photoelectron spectroscopy, electrochemically active surface area, and other physicochemical and electrochemical analyses reveal that its great OER catalytic activity is ascribed to the Ni-Co hydroxides with modular 2-Dimensional layered structure, the synergistic interactions among the Fe(III) species and Ni, Co metal centers, and the improved hydrophily endowed by the incorporation of N-doped carbon hydrogel. This work might provide a useful and general strategy to design and synthesize high-performance metal (hydr)oxides OER electrocatalysts.

A Ag/C3N4 nanocomposite with optimum Ag content is an efficient and green photocatalyst for pollutant degradation under visible light irradiation. In this study, we synthesized Ag NPs using NaBH4 and the squeezed out liquid (SOL) of plant biomass. The Ag NPs thus obtained have been loaded to C3N4 to form Ag/C3N4 nanocomposites that show superior photocatalytic performance toward Rhodamine B (RhB) under visible light irradiation. The photocatalytic activity of both biogenic and chemogenic Ag/C3N4 nanocomposites with different Ag contents is compared. Results show that the biogenically synthesized Ag/C3N4 exhibits better photocatalytic performance than the chemosynthetic composite. Of all the different nanocomposites prepared in this study, Ag48/C3N4 (0.048% of Ag content) exhibits excellent photoreactivity, with a reaction rate constant (k) 7-fold higher that the chemosynthetic Ag/C3N4. The observed improvement in the photoreactivity is mainly attributed to the high dispersion of Ag NPs on C3N4, facilitate...

Lignin valorization is considered an important part of the modern biorefinery scheme. The unique structure and composition of lignin may offer many effective routes to produce several bulk chemicals and functional materials. Thermochemical conversion of lignin to synthesize value-added functional materials has recently attracted a lot of attention. In this review, we have presented currently available approaches and strategies for the thermochemical conversion of lignin to functional carbon materials. The transformation behavior and mechanism of lignin during the thermochemical process (e.g., pyrolysis and hydrothermal carbonization) are illuminated. The characteristics (structure and surface chemistry) of lignin-based functional carbon materials are summarized systematically. The advances in the functionalization of lignin-based carbon materials (surface functionality tuning and porosity tailoring) and the applications of lignin-based functional carbon materials in the fields of catalysis, energy storage, and pollutant removal are reviewed. Perspectives on how lignin-based functional materials would develop and, especially, in which fields the use of these functionalized materials could be expanded are discussed. This review clearly shows that a rational design of the functionalized lignin-based materials will lead to a rich family of hybrid functional carbon materials with various applications toward a green and sustainable future.

Ni–NiFe2O4/carbon nanofiber (Ni–NiFe2O4/CNF) composite materials were synthesized by fast pyrolysis of the FeCl3 and NiCl2 preloaded biomass. The as-synthesized materials showed a favourable catalytic performance in the hydrogenation of aromatic nitro compounds with high yield and selectivity. The catalyst can be easily separated using a magnet and its catalytic activity remains almost unchanged after 7-time reuse.

A chemical modified biochar with abundant amino groups for heavy metal removal was prepared using polyethylenimine (PEI) as a modification reagent, and used as an adsorbent for the removal of Cr(VI) from aqueous solution. The biochars before and after modification were characterized by Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy etc. The adsorption of Cr(VI) by the modified biochar was obeyed pseudo-second-order kinetic model and Langmuir adsorption isotherm model. Its maximum adsorption capacity was 435.7 mg/g, which was much higher than that of pristine biochar (23.09 mg/g). Results also indicated that the removal of Cr(VI) by the PEI modified biochar depended on solution pH, and a low pH value was favorable for the Cr(VI) removal. The results herein revealed that the PEI modified biochar had a good potential as a suitable material for sorption and detoxification of Cr(VI) from aqueous solution.

Tetracycline (TC), a commonly used personal care and veterinary drug, is produced in large-scale, during which high concentrations of wastewater is discharged into environment and difficult to biodegrade. Adsorption is a cost-effective and environment-friendly approach to TC wastewater. In this study, ubiquitous rice husk biochar was modified by methanol to improve TC adsorption capacities and reduce the inherent organic compound content in the biochar. The modified biochar showed approximately 45.6% enhancement of adsorption capacity in 12 h and 17.2% in equilibrium time compared with Ori-char. X-ray photoelectron spectroscopy suggested that the main factor responsible for the enhancement of TC adsorption is the change in O-containing groups in the modified biochar, which affects π–π electron–donor–acceptor interactions between the biochar and TC. The fixed bed experiment show that the effective filtration volume of MeOH-char is 1059 bed volumes, which is approximately 2-fold of that of Ori-char.

This article explored the design and implementation problems of Sustainability Assessment Data Warehouse for Shanghai Airport. According to the characteristics of Shanghai airport, the airport data collection platform layer and six theme databases were designed in this paper. This paper also designed the operator assessment models and the user evaluation models, which strong guaranteed and supported the validity of the evaluation of sustainable development at the airport.

As an emerging new class of materials comprising two different metals, bimetallic nanoparticles (NPs) exhibit new functions because of the synergistic rather than merely additive effects of the metals. Compared with monometallic Fe NPs, bimetallic Fe NPs have markedly enhanced physical and chemical properties, including magnetism and reducing ability. However, bimetallic Fe NPs with controlled morphology, size, composition, and structure are often difficult to synthesize. This review summarizes recent advances in the synthesis and environmental application of bimetallic Fe NPs. Different methods of synthesizing bimetallic NPs with different structures, sizes, compositions, and surface properties are summarized. Focus is also given to the catalytic elimination of various environmental pollutants using bimetallic Fe NPs because they have emerged as a promising catalyst for environmental remediation. Their strong reducing ability can be used to remove numerous environmental pollutants (e.g., heavy metals, halogenated organic compounds, nitro and azo compounds, and oxyanions). Reactions between the bimetallic NPs and these pollutants mainly fall into four categories: (1) catalytic replacement reaction for heavy-metal removal, (2) hydrodehalogenation for halogenated hydrocarbons, (3) nitro and azo hydrogenation for nitro and azo compounds, and (4) hydrodeoxygenation for oxyanions. Compared with monometallic Fe NPs, bimetallic Fe NPs have considerable separability and catalytic ability to degrade nonbiodegradable pollutants.

A two-step digestion–ultraviolet (UV) spectrophotometry method for total nitrogen (N) determination in solid samples is described in this work. Three influencing factors (amount of hydrogen peroxide, amount of sulfuric acid, and digestion time) of the digestion are optimized, and for digestion of a 0.1-g solid sample, the optimal conditions are 0.5 mL of sulfuric acid, 0.2 mL of hydrogen peroxide, and 40 min of the digestion time. The results of ion chromatography show that under the optimal conditions the organic nitrogen almost quantitatively mineralizes into ammonium in the first digestion. The nitrogen content in six real samples has been analyzed under the optimal conditions, and the nitrogen recovery rates of standard compounds added in the real samples were between 88% and 99%. The results obtained by two-step digestion–UV spectrophotometry method are consistent with those by classical Kjeldahl method (correlation coefficient is 0.9999). The possible degradation pathways of three amino acids were a...