Controlled oxygen doping in highly dispersed Ni-loaded g-C3N4 nanotubes for efficient photocatalytic H2O2 production

Hydrogen peroxide (HO) is both a key component in several industrial processes and a promising liquid fuel. The production of HO by solar photocatalysis is a suitable strategy to convert and store solar energy into chemical energy. Here we report an oxygen-doped tubular g-CN with uniformly dispersed nickel nanoparticles for efficient photocatalytic HO generation. The hollow structure of the tubular g-CN provides a large surface with a high density of reactive sites and efficient visible light absorption during the photocatalytic reaction. The oxygen doping and Ni loading enable a fast separation of photogenerated charge carriers and a high selectivity toward the two-electron process during the oxygen reduction reaction (ORR). The optimized composition, Ni/OtCN, displays an HO production rate of 2464 μmol g·h, which is eightfold higher than that of bulk g-CN under visible light irradiation (λ > 420 nm), and achieves an apparent quantum yield (AQY) of 28.2% at 380 nm and 14.9% at 420 nm.IREC and ICN2 acknowledge funding from Generalitat de Catalunya, projects 2017 SGR 1246 and 2017 SGR 327, respectively. The authors thank the support from the project COMBENERY (PID2019-105490RB-C32) and NANOGEN (PID2020-116093RB-C43), funded by MCIN/ AEI/10.13039/501100011033/. ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706) and is funded by the CERCAProgramme / Generalitat de Catalunya. Baoying Li and Jianbin Chen greatly appreciate the financial support from the National Natural Science Foundation of China (Nos. 22171154 & 21801144), the Youth Innovative Talents Recruitment and Cultivation Program of Shandong Higher Education, The Project Supported by the Foundation (No. ZZ20190312) of State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences)

SnS2/g-C3N4/graphite nanocomposites as durable lithium-ion battery anode with high pseudocapacitance contribution

Altres ajuts: the CERCA Programme /Generalitat de Catalunya. Part of the present work has been performed in the framework of Universitat Autònoma de Barcelona Materials Science PhD program.Tin disulfide is a promising anode material for Li-ion batteries (LIB) owing to its high theoretical capacity and the abundance of its composing elements. However, bare SnS suffers from low electrical conductivity and large volume expansion, which results in poor rate performance and cycling stability. Herein, we present a solution-based strategy to grow SnS nanostructures within a matrix of porous g-CN (CN) and high electrical conductivity graphite plates (GPs). We test the resulting nanocomposite as anode in LIBs. First, SnS nanostructures with different geometries are tested, to find out that thin SnS nanoplates (SnS-NPLs) provide the highest performances. Such SnS-NPLs, incorporated into hierarchical SnS/CN/GP nanocomposites, display excellent rate capabilities (536.5 mA h g at 2.0 A g) and an outstanding stability (∼99.7% retention after 400 cycles), which are partially associated with a high pseudocapacitance contribution (88.8% at 1.0 mV s). The excellent electrochemical properties of these nanocomposites are ascribed to the synergy created between the three nanocomposite components: i) thin SnS-NPLs provide a large surface for rapid Li-ion intercalation and a proper geometry to stand volume expansions during lithiation/delithiation cycles; ii) porous CN prevents SnS-NPLs aggregation, habilitates efficient channels for Li-ion diffusion and buffer stresses associated to SnS volume changes; and iii) conductive GPs allow an efficient charge transport

Effect of Trichoderma viride on rhizosphere microbial communities and biocontrol of soybean root rot

Biological seed dressing is a cost-effective means to protect plant roots from pathogens. Trichoderma is generally considered as one of the most common biological seed dressings. However, there is still a dearth of information on the effects of Trichoderma on microbial community of rhizosphere soil. High-throughput sequencing was used to analyze the effects of Trichoderma viride and a chemical fungicide on microbial community of soybean rhizosphere soil. The results showed that both T. viride and chemical fungicide could significantly reduce the disease index of soybean (15.11% for Trichoderma and 17.33% for Chemical), while no significant difference was observed between them. Both T. viride and chemical fungicide could affect the structure of rhizosphere microbial community, they increased the β-diversity of microbial community and significantly reduce the relative abundance of Saprotroph-Symbiotroph. Chemical fungicide could reduce the complexity and stability of co-occurrence network. However, T. viride is beneficial for maintaining network stability and increasing network complexity. There were 31 bacterial genera and 21 fungal genera significantly correlated with the disease index. Furthermore, several potential plant pathogenic microorganisms were also positively correlated with disease index, such as Fusarium, Aspergillus, Conocybe, Naganishia, and Monocillium. From this work, T. viride may be used as a substitute for chemical fungicide to control soybean root rot and be more friendly to soil microecology

In Situ Electrochemical Oxidation of Cu2S into CuO Nanowires as a Durable and Efficient Electrocatalyst for Oxygen Evolution Reaction

Development of cost-effective oxygen evolution catalysts is of capital importance for the deployment of large-scale energy-storage systems based on metal-air batteries and reversible fuel cells. In this direction, a wide range of materials have been explored, especially under more favorable alkaline conditions, and several metal chalcogenides have particularly demonstrated excellent performances. However, chalcogenides are thermodynamically less stable than the corresponding oxides and hydroxides under oxidizing potentials in alkaline media. Although this instability in some cases has prevented the application of chalcogenides as oxygen evolution catalysts and it has been disregarded in some others, we propose to use it in our favor to produce high-performance oxygen evolution catalysts. We characterize here the in situ chemical, structural, and morphological transformation during the oxygen evolution reaction (OER) in alkaline media of CuS into CuO nanowires, mediating the intermediate formation of Cu(OH). We also test their OER activity and stability under OER operation in alkaline media and compare them with the OER performance of Cu(OH) and CuO nanostructures directly grown on the surface of a copper mesh. We demonstrate here that CuO produced from in situ electrochemical oxidation of CuS displays an extraordinary electrocatalytic performance toward OER, well above that of CuO and Cu(OH) synthesized without this transformation

Selective Ethylene Glycol Oxidation to Formate on Nickel Selenide with Simultaneous Evolution of Hydrogen

There is an urgent need for cost-effective strategies to produce hydrogen from renewable net-zero carbon sources using renewable energies. In this context, the electrochemical hydrogen evolution reaction can be boosted by replacing the oxygen evolution reaction with the oxidation of small organic molecules, such as ethylene glycol (EG). EG is a particularly interesting organic liquid with two hydroxyl groups that can be transformed into a variety of C1 and C2 chemicals, depending on the catalyst and reaction conditions. Here, a catalyst is demonstrated for the selective EG oxidation reaction (EGOR) to formate on nickel selenide. The catalyst nanoparticle (NP) morphology and crystallographic phase are tuned to maximize its performance. The optimized NiS electrocatalyst requires just 1.395 V to drive a current density of 50 mA cm −2 in 1 potassium hydroxide (KOH) and 1 EG. A combination of in situ electrochemical infrared absorption spectroscopy (IRAS) to monitor the electrocatalytic process and ex situ analysis of the electrolyte composition shows the main EGOR product is formate, with a Faradaic efficiency above 80%. Additionally, C2 chemicals such as glycolate and oxalate are detected and quantified as minor products. Density functional theory (DFT) calculations of the reaction process show the glycol-to-oxalate pathway to be favored via the glycolate formation, where the C-C bond is broken and further electro-oxidized to formate. A combination of in situ and ex situ analysis shows the main product of the ethylene glycol (EG) oxidation reaction (EGOR) is formate with a Faradaic efficiency above 80%, and glycolate and oxalate as minor chemicals on nickel selenide nanoparticles (NPs). Further density functional theory (DFT) calculation reveals the electrooxidation mechanism to these products

Key defatting tissue pretreatment protocol for enhanced MALDI MS Imaging of peptide biomarkers visualization in the castor beans and their attribution applications

IntroductionCastor bean or ricin-induced intoxication or terror events have threatened public security and social safety. Potential resources or materials include beans, raw extraction products, crude toxins, and purified ricin. The traceability of the origins of castor beans is thus essential for forensic and anti-terror investigations. As a new imaging technique with label-free, rapid, and high throughput features, matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) has been gradually stressed in plant research. However, sample preparation approaches for plant tissues still face severe challenges, especially for some lipid-rich, water-rich, or fragile tissues. Proper tissue washing procedures would be pivotal, but little information is known until now.MethodsFor castor beans containing plenty of lipids that were fragile when handled, we developed a comprehensive tissue pretreatment protocol. Eight washing procedures aimed at removing lipids were discussed in detail. We then constructed a robust MALDI-MSI method to enhance the detection sensitivity of RCBs in castor beans.Results and DiscussionA modified six-step washing procedure was chosen as the most critical parameter regarding the MSI visualization of peptides. The method was further applied to visualize and quantify the defense peptides, Ricinus communis biomarkers (RCBs) in castor bean tissue sections from nine different geographic sources from China, Pakistan, and Ethiopia. Multivariate statistical models, including deep learning network, revealed a valuable classification clue concerning nationality and altitude

Selective Ethylene Glycol Oxidation to Formate on Nickel Selenide with Simultaneous Evolution of Hydrogen

There is an urgent need for cost-effective strategies to produce hydrogen from renewable net-zero carbon sources using renewable energies. In this context, the electrochemical hydrogen evolution reaction can be boosted by replacing the oxygen evolution reaction with the oxidation of small organic molecules, such as ethylene glycol (EG). EG is a particularly interesting organic liquid with two hydroxyl groups that can be transformed into a variety of C1 and C2 chemicals, depending on the catalyst and reaction conditions. Here, a catalyst is demonstrated for the selective EG oxidation reaction (EGOR) to formate on nickel selenide. The catalyst nanoparticle (NP) morphology and crystallographic phase are tuned to maximize its performance. The optimized NiS electrocatalyst requires just 1.395 V to drive a current density of 50 mA cm-2 in 1 m potassium hydroxide (KOH) and 1 m EG. A combination of in situ electrochemical infrared absorption spectroscopy (IRAS) to monitor the electrocatalytic process and ex situ analysis of the electrolyte composition shows the main EGOR product is formate, with a Faradaic efficiency above 80%. Additionally, C2 chemicals such as glycolate and oxalate are detected and quantified as minor products. Density functional theory (DFT) calculations of the reaction process show the glycol-to-oxalate pathway to be favored via the glycolate formation, where the CC bond is broken and further electro-oxidized to formate.This work was supported by the start-up funding at Chengdu University and the Natural Science Foundation of Sichuan (NSFSC) project funded by the Science and Technology Department of Sichuan Province (Project No. 2022NSFSC1229), and also the open project from Hebei Key Laboratory of Photoelectric Control on Surface and Interface (Project No. ZD2022003). It was also supported by the European Regional Development Funds and by the Spanish Ministerio de Ciencia e Innovación through the project COMBENERGY (Project No. PID2019-105490RB-C32). Y.-Y.Y. acknowledges funding from the National Natural Science Foundation of China (NSFC, Grant No. 22172121), the Natural Science Foundation of Sichuan Province (NSFSC, Grant No. 23NSFSC6266) and the Fundamental Research Funds for the Central Universities, Southwest Minzu University (Grant No. xiao2021102). X.H. has received funding from the CSC-UAB Ph.D. scholarship program. X.H. and J.A. acknowledge funding from Generalitat de Catalunya 2021SGR00457. ICN2 acknowledges support from the Severo Ochoa Programme from Spanish MCIN/AEI (Grant No. CEX2021-001214-S). ICN2 authors thank the support from the project NANOGEN (PID2020-116093RB-C43), funded by MCIN/AEI/10.13039/501100011033/ and by "EDRF a way of making Europe", by the "European Union". IREC and ICN2 were funded by the CERCA Programme/Generalitat de Catalunya. Part of the present work was performed in the framework of the Universitat Autònoma de Barcelona Materials Science Ph.D. program. This study was also supported by MCIN with funding from European Union NextGenerationEU (Grant No. PRTR-C17.I1) and Generalitat de Catalunya.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2021-001214-S)Peer reviewe

Supporting Information for Adv. Sci., DOI 10.1002/advs.202300841 Selective Ethylene Glycol Oxidation to Formate on Nickel Selenide with Simultaneous Evolution of Hydrogen

16 pages. -- SEM-EDS characterization. -- HRTEM characterization. -- XPS spectra. -- Electrochemical characterization. -- EGOR Electrocatalytic performance comparision with previous results. -- Sample characterization after CA operation. -- IC Profile. -- Electrolytic cell coupling HER and EGOR. -- DFT data.Peer reviewe

Identifying the Role of the Cationic Geometric Configuration in Spinel Catalysts for Polysulfide Conversion in Sodium-Sulfur Batteries

An AB2X4 spinel structure, with tetrahedral A and octahedral B sites, is a paradigmatic class of catalysts with several possible geometric configurations and numerous applications, including polysulfide conversion in metal-sulfur batteries. Nonetheless, the influence of the geometric configuration and composition on the mechanisms of catalysis and the precise manner in which spinel catalysts facilitate the conversion of polysulfides remain unknown. To enable controlled exposure of single active configurations, herein, Cotd2+ and Cooh3+ in Co3O4 catalysts for sodium polysulfide conversion are in large part replaced by Fetd2+ and Feoh3+, respectively, generating FeCo2O4 and CoFe2O4. Through an examination of electrochemical activation energies, the characterization of symmetric cells, and theoretical calculations, we determine that Cooh3+ serves as the active site for the breaking of S-S bonds, while Cotd2+ functions as the active site for the formation of S-Na bonds. The current study underlines the subtle relationship between activity and geometric configurations of spinel catalysts, providing unique insights for the rational development of improved catalysts by optimizing their atomic geometric configuration.This work was supported by the Innovation fund for small and medium-sized Enterprises in Gansu Province (No. 22CX3JA006), Lanzhou Talent Innovation and Entrepreneurship Project (No. 2022-2-81), National Natural Science Foundation of China (Grant Nos. 61801200), and partially by the Fundamental Research Funds for the Central Universities (Grant No.: lzujbky-2021-it33). J.S. Li acknowledges financial support from the Natural Science Foundation of Sichuan province (2022NSFSC1229). ICN2 acknowledges funding from Generalitat de Catalunya 2021SGR00457. This study is part of the Advanced Materials programme and was supported by MCIN with funding from European Union NextGenerationEU (PRTR-C17.I1) and by Generalitat de Catalunya. The authors thank the support from the project NANOGEN (PID2020-116093RB-C43), funded by MCIN/AEI/10.13039/501100011033/ and by “ERDF A way of making Europe”, by the “European Union”. ICN2 is supported by the Severo Ochoa program from Spanish MCIN/AEI (Grant No.: CEX2021-001214-S) and is funded by the CERCA Programme/Generalitat de Catalunya. AGM has received funding from Grant RYC2021-033479-I funded by MCIN/AEI/10.13039/501100011033 and by European Union NextGenerationEU/PRTR. L.B. thanks the Ministry of Science and Innovation of Spain through the OXISHOT project (PID2021-128410OB-I00). ICN2 acknowledges funding from Project IU16-014206 (METCAM-FIB) from Generalitat de Catalunya and by “ERDF A way of making Europe”, by the European Union.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe