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Currently, promoting solar absorption ability and photoexcited charge separation and transfer of semiconductors is of significance for enhancing their solar-to-hydrogen (STH) efficiency. Hollow-structured design and element doping strategy have proven to be effective in strengthening solar absorption and manipulating the charge dynamics. Herein, an ingenious design of doping phosphors (P) into hollow-structured CdS octahedrons is applied for achieving effective photocatalytic hydrogen production. The P-doped CdS semiconductor has a hollow interior for enhancing the photon absorbance and a narrow bandgap with upshift of valence band for facilitating photoinduced charge separation and transport, all of which contribute to their improved photocatalytic performance. Consequently, the synergistic effect in the designed archicture leads to an enhanced hydrogen production rate of up to 9.58 mmol·g−1 h−1, being about 11.7 fold higher than the reported CdS nanorods. Our work offers a new way for developing other types of sulfur-based semiconductors towards effective solar-to-hydrogen conversion. [Display omitted] • Phosphors-doped CdS hollow octahedrons have been successfully synthesized. • P-doped CdS exhibits an enhanced photocatalytic hydrogen production rate. • It is attributed to synergy effect of structural design and dopant strategy. • The present approach gives a reference to design advanced semiconductors. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) carbonaceous aerogel derived from biomass bacterial cellulose (BC) is introduced as a flexible framework for iron oxides in Li-ion batteries (LIBs). The 3D carbonized BC (CBC) with highly interconnected nanofibrous structure exhibits good electrical conductivity and mechanical stability. The amorphous Fe 2 O 3 is tightly coated on the nanofibers of CBC through a simple in situ thermal decomposition method. The obtained amorphous Fe 2 O 3 anode (denoted as A-Fe 2 O 3 @CBC) exhibits stable cycling performance and high rate capability when assembled into a half-cell, which is supposed to benefit from the well-dispersed Fe 2 O 3 nanoshells and the hierarchical pores in A-Fe 2 O 3 @CBC composite. The rational design of the nanostructure could improve the transportation of electrons/ions and effectively alleviate volume changes of Fe 2 O 3 during the electrochemical cycling. Meanwhile, the amorphous nature of the Fe 2 O 3 in anode provides an enhanced capacitive-like lithium storage and flexible structure of the active materials, resulting in much higher specific capacity and longer cycle life when compared with its crystalline counterpart. This work provides a promising approach to design and construct the flexible metal oxide anode materials based on 3D carbonaceous aerogel for high-performance LIBs. [ABSTRACT FROM AUTHOR]

Efficient solar absorption and photoinduced charge separation are extremely important for solar-energy conversion on semiconductor photocatalysts. To advance the photocatalytic performance, we developed a general templated-assisted reverse cation exchange strategy to successfully synthesize hollow-structured CdS semiconductors with the textile structural surface. The crystal phase, particle morphology, optical/electrical properties, and photocatalytic performance of the as-syntheszied sample are investiagted by XRD, SEM, TEM, XPS, DSR, PL, ESR photoelectrochemical measurements, and Photocatalytic H 2 evolution test. The final CdS sample exhibits an enhanced photocatalytic hydrogen evolution rate of up to 965 μmol·g−1 h−1, 2.8 times higher than the reported CdS nanorods. Based on the experimental and characterization results, the improved photocatalytic activity of the cadmium sulfide semiconductor can be ascribed to the special hollow cubic structure with a thin shell, which can enhance the light-harvesting ability and provide abundant photocatalytic active sites for facilitating the separation of photogenerated electron/hole pairs. This synthetic strategy may pave a new path for the rational design of efficient sulfur-based semiconductor photocatalysts for solar driven H 2 production. Hollow-structured CdS cubes have been successfully synthesized via reverse cation exchange strategy for enhanced photocatalytic hydrogen production. [Display omitted] • CdS nanocubes were synthesized via templated-assisted cation exchange strategy. • CdS exhibits enhanced photocatalytic H 2 evolution rate of up to 965 μmol·g−1 h−1. • The photocatalytic performance is attributed to hollow structure of CdS nanocubes. • This strategy may pave a new way for rational design of efficient photocatalysts. [ABSTRACT FROM AUTHOR]

Metal sulfides have been considered as potential candidates for photocatalytic hydrogen production, but their practical applications are still limited by incident light utilization and charge separation despite the impressive advances in recent decades. To address these challenges, the construction of hollow nanostructure with exposing high active facets offers a desirable pathway for developing novel and high-efficiency photocatalysts. Here, by taking wurtzite CdS as an example, we first develop a general template-assisted cation exchange route for the preparation of hollow CdS nanostructures with diverse exposed facets. The obtained hollow CdS octahedrons with dominant {101} facets exhibit superior photocatalytic H 2 evolution rate under visible-light irradiation compared with common CdS nanorods. According to the characterization results and density functional theory calculations, the excellent photocatalytic performance is attributed to the construction of hollow nano-octahedrons with exposed {101} active facets, which facilitates efficient light harvesting and photoinduced charge separation of CdS photocatalyst. The present approach gives a reference to design advanced semiconductors with remarkable photocatalytic activity for realizing efficient solar-to-chemical conversion. [Display omitted] • Hollow CdS with different exposed facets were successfully synthesized via a general template-assisted cation exchange strategy. • Hollow-structured CdS octahedrons with exposed {101} facets exhibit superior photocatalytic H2 evolution rate. • The improved photocatalytic performance is attributed to the construction of hollow octahedrons with {101} active facets. • This strategy is exploited to other sulfide-based photocatalysts for realizing efficient solar-to-chemical conversion. [ABSTRACT FROM AUTHOR]

Two-dimensional Sn-based metal compounds (e.g. SnS, SnS 2 and SnO 2 ) are exceptionally attractive due to their excellent ion intercalation response and are suitable for use in energy storage devices (e.g. lithium-ion batteries and supercapacitors). However, the application of these dichalcogenides in Li-ion batteries is hindered by limitations in large-scale solution synthesis of SnS nanobelts. In this study, we developed a universal hydrothermal approach for the synthesis of SnS nanobelts and proposed an underlying mechanism for the formation reaction. When used as anode materials for lithium-ion batteries, SnS nanobelts maintain a discharge capacity of 889.9 mAhg −1 after 50 cycles at a current density of 0.1 A/g. The nanobelts also exhibit high electrochemical performance, high rate capacity, and high reversible capacity. These results demonstrate that SnS nanobelts are potential anode materials for high-performance energy storage applications. [ABSTRACT FROM AUTHOR]

Graphene-based nanocomposites have been widely investigated as promising anode materials because of the high specific capacity and good rate capability. However, effective distributing the nanomaterials into graphene conductive network still remains some challenges. In this study, the supercritical carbon dioxide (SC-CO 2 ) route as a good strategy is developed to prepare SnS 2 /reduced graphene oxide (RGO) nanocomposites, which integrates the complementary effect of ultrasmall SnS 2 nanopaticle and RGO nanosheet in the nanocompositions. The SnS 2 /RGO nanocomposite exhibits high initial discharge capacity of 1466.1 mA h g −1 (100 mA g −1 ), good capacity retention of about 492 mA h g −1 (100 mA g −1 ) after 70 cycles and good rate capacity as an anode material for lithium ion batteries. These results demonstrate that supercritical CO 2 (SC-CO 2 ) possess significant technological value to enhance the energy storage properties of other two-dimensional (2D) nanocomposites. [ABSTRACT FROM AUTHOR]

Two-dimensional transition-metal dichalcogenides, such as tungsten disulfide (WS 2 ), have been actively studied as suitable candidates for anode materials used in lithium ion batteries recently, due to their remarkable ion intercalation properties. However, the difficulties in the synthesis of phase-pure WS 2 , restacking between WS 2 nanosheets, low electronic conductivity and brittle nature of WS 2 severely limit its Li-ion batteries application. Here, we adopt a one-pot method for synthesizing of WS 2 /reduced Graphene Oxide (rGO) composite to improve the battery performance dramatically. The WS 2 /rGO anode shows a stable discharge capacity of 431.2 mAh/g, at a current density of 0.1 A/g after 100 cycles, while the capacity of bare WS 2 is only 65.5 mAh/g under the same condition. The added graphene oxide is reduced to rGO in reaction process and constitute stable composite with WS 2 , not only avoiding the restacking between WS 2 nanosheets and improving the conductive properties, but also promoting the reduction of WO 3 effectively. Our work may provide a possible route to avoid oxygen impurities in transition metal dichalcogenides. [ABSTRACT FROM AUTHOR]

Organic anodes for K-storage have attracted much attention because of high theoretical capacity, low cost and extensive natural resource although facing serious dissolving issues with conventional electrolytes and persistent capacity decay. Therefore, 2-methylimidazole (mIm), an imidazolium-based small molecule restricted with high electronic conductivity carbon nanotubes (mIm/CNTs) is applied for potassium-ion batteries (PIBs). Furthermore, this as-prepared anode is accompanied to the potassium bis(fluorosulfonyl)imide (KFSI)-ethylene carbonate (EC) and diethyl carbonate (DEC) electrolytes (KFSI/EC + DEC) with modifiable solvation structures. At current density of 50 mA g−1, the mIm/CNTs composite coupled with the optimized 3 mol L−1 KFSI/EC + DEC electrolyte provides an average reversible capacity of 240 mAh g−1 (composites) with coulombic efficiency (CE) of 99.5 %. After 500 cycles, a high sustained capacity of 200 mAh g−1 (composites) is attained at 200 mA g−1. This enhanced K-storage performance of mIm/CNTs in 3 mol L−1 KFSI/EC + DEC electrolyte can be attributed to distinctive solvation structure, which is dominated by contact ion pairs (CIPs) and aggregates (AGGs). This structure intensively mitigates dissolution issues and greatly promotes K+ reaction kinetics. This work emphasizes the significance of electrolyte regulation for organic anodes and will supply a comprehensive appreciating of electrochemistry performance for advanced energy storage systems. A novel mIm/CNTs anode, fabricated via restricting mIm with high electronic conductivity carbon nanotubes (CNTs), exhibited a high average reversible capacity of 240 mAh g−1 (composites) at 50 mA g−1 with a high coulombic efficiency (CE) up to 99.5 %, and maintained 200 mAh g−1 (composites) after 500 cycles at 200 mA g−1 (99.3 % of CE) in 3 M KFSI/EC + DEC electrolyte, demonstrating the superior electrochemical performance with enhanced capacity and cycle life when compared with previous organic anode potassium-ion batteries. [Display omitted] • A novel imidazolium-based molecule is proposed as K-storage anode. • An optimized ester-based electrolyte is matched with the organic anode. • Superior capacity of 240 mAh g−1 after 200 cycles at 50 mA g−1 is achieved. • Enhanced properties are attributed to electrolyte regulation. [ABSTRACT FROM AUTHOR]

Pyr 13 + effects on ionic liquid-based electrolytes were firstly and thoroughly explored in K-ion batteries, producing a special solvation structure and dense, elastic SEI on PTA/CMK3 anode, thus satisfactory compatibility with K metal and excellent K-storage of 190 mAh/g (composites) at 200 mA/g after 600 cycles were obtained in the optimized PTA/CMK3||KFSI/Pyr 13 FSI. [Display omitted] • Ionic liquid electrolytes of 1.0 M KFSI/Pyr 13 FSI was first designed for PTA/CMK3 composites in potassium-ion batteries. • Stable and robust F-rich and N-rich SEI layer was generated by facilely regulatable content of K+-FSI− aggregates. • PTA/CMK3 composites delivered a reversible capacity of 190 mAh/g (composites) at 200 mA/g even after 600 cycles. Ionic liquid-based electrolytes (ILEs) show great potential in mitigating the dissolution of organic electrode materials as well as manipulating the interfacial electrochemistry for long lifespan of potassium-ion batteries (PIBs). Herein, KFSI/Pyr 13 FSI ILEs with varying K+ and Pyr 13 + ratios were designed to match a novel organic K-storage anode of p-toluic acid/CMK3 (PTA/CMK3). These ILEs exhibited facilely manipulated solvation structures, resulting into excellent compatibility with K-metal as well as promotion of the generation of robust solid-electrolyte interphase (SEI) for stable K-storage. As a result, the optimized PTA/CMK3||KFSI/Pyr 13 FSI K-storage system delivered a reversible capacity of 190 mAh/g (composites) alongside high coulomb efficiency of 99.7 % at a current density of 200 mA/g for 600 cycles. This work provides a fresh insight on rational design of ILEs-based advanced PIBs with high energy density and safety. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel hydrogen accelerated oxygen reduction Fenton reaction system was constructed based on Pd/UiO-66(Zr), H 2 and Fe(II). • The Pd/UiO-66(Zr) promoted to selfgenerated H 2 O 2 by the 2e ORR pathway and reduce Fe(III) directly via reduction of [H]. • As high as 100 % TMP removal was achieved in 60 min by MHORF-UiO-66(Zr) system. • Mechanisms of H 2 O 2 generation and Fe(III) reduction were proposed. Both the iron sludge and usage of H 2 O 2 restrict the promotion of the Fenton reaction. Herein, we proposed a hydrogen-accelerated oxygen reduction Fenton reaction system named MHORF-UiO-66(Zr) to try to solve the two problems under normal temperature and pressure. The active hydrogen, which is derived from H 2 catalyzed by the composite of Pd/UiO-66(Zr), could accelerate the reduction of Fe(III) and promote the electron transfer of two-electron oxygen reduction reaction to realize the self-generation of H 2 O 2. And 45.9 mM of H 2 O 2 could be detected. As expected, 91 % of trimethoprim (TMP) could be degraded within 30 min in this system in the condition of 25 μM Fe(II), H 2 30 mL·min−1, and Pd/UiO-66(Zr) 2g·L−1, which was 2.94 times that of the control Fenton system. Based on these results, the feasibility of fundamentally achieving zero emission of iron sludge was successfully verified. It was confirmed that both the hydroxyl radical and singlet oxygen played the dominant roles during the reaction process through the analysis of electron spin resonance spectroscopy. After six reaction cycles, the removal efficiency of TMP could be maintained at least 94 %. It found that both the properties and morphology of this composite could remain based on the systematic characterization. [ABSTRACT FROM AUTHOR]

Abstract: CuO nanoparticles are directly formed on graphene nanosheets through the in situ chemical decomposition of Cu(NO3)2·3H2O and are anchored tightly on the graphene surface. The lithiation-induced strain is naturally accommodated, owing to the constraint effect of the graphene matrix. Electrochemical characterization shows that CuO nanoparticles anchored on graphene sample exhibits a high capacity of about 660mAh/g at a discharge current density of 100mA/g and a good cycling ability. During the charge–discharge process, graphene nanosheets not only served as a three-dimensional conductive network for CuO nanoparticles, but also improve the detachment and agglomeration of CuO nanoparticles. This CuO/graphene nanocomposite displays superior Li-battery performance with large reversible capacity, excellent cyclic performance, and good rate capability. [Copyright &y& Elsevier]

Acute pancreatitis (AP) is characterized by excessive release of pro-inflammatory cytokines and provokes multiorgan dysfunction. Disruption of the intestinal epithelium often occurs during and following acute pancreatitis and may aggravate systemic organ injuries. Although it has been widely investigated, to date, there is no satisfactory clinical therapy to restore the inflammatory damage. BML-111 is an endogenous lipid mediator that is analogous to LipoxinA4. It has been shown that BML-111 has a stable and potent anti-inflammatory ability. However, it is unclear whether BML-111 is involved in the process of relieving acute pancreatitis and its induced intestinal barrier damage, and the underlying mechanism of this effect. Here, we demonstrated that BML-111 could enhance the expression of E-cadherin, alleviate apoptosis, and mitigate the accumulation of reactive oxygen species in intestinal epithelial cells, thereby contributing to the anti-inflammatory efficacy in vitro and in vivo. Mechanistically, BML-111 upregulates the expression of Nrf2, which is a key regulator of the antioxidant response, and activates its downstream HO-1/NQO-1 pathway to protect against oxidative stress-induced cell death and tissue injury, consequently ameliorating pancreatitis and intestinal epithelium injury. In Nrf2-deficient cell and Nrf2-knockout mouse models, the depletion of Nrf2 blocked BML-111-induced antioxidant effects and thus was unable to exert protective effects in tissue. Taken together, BML-111 attenuated AP-related intestinal injury via an Nrf2-dependent antioxidant mechanism. Targeting this pathway is a potential therapeutic approach for AP-related intestinal injury. Image 1 • Oxidative stress is critical for acute pancreatitis-intestinal injury pathogenesis. • We tested the BML-111 as antioxidant therapy for intestinal damage following AP. • BML-111 shows therapeutic potential for AP-intestinal injury in vivo and vitro. • BML-111 enhances E-cadherin expression, alleviates apoptosis and mitigates ROS accumulation. • BML-111 exert the effectively efficacy by activating antioxidant enzymes Nrf2 signaling. [ABSTRACT FROM AUTHOR]

Comparison research on the flame temperature, soot productions, the morphology, the nanostructure and the oxidation reactivity of the soot particles sampled from ethylene inverse diffusion flames with blending biodiesel surrogates of saturated methyl butyrate (MB) and unsaturated methyl crotonate (MC) were carried out. The flame temperature was measured by a thermocouple, soot morphology and nanostructures were investigated by using Transmission Electron Microscopy (TEM) and High Resolution TEM, the graphitization and oxidation reactivity were analyzed by X-ray Diffraction and Thermogravimetric Analyzer. Effects of blending rate of biodiesel surrogates of MB and MC were discussed. The results show that, with the increasing of MB additions, the flame temperatures is lifted, soot production increases firstly and then decreases because of a comprehensive effect depending on the oxygen content from oxygenated saturated MB. With MC blending, the flame temperature declines, but the soot production jumps approximately double due to the synergistic effect of C C double bonds and oxygen functional groups in oxygenated unsaturated MC. Because of oxygen components in MB and MC, soot particles sampled from MB and MC blending flames have been oxidized to be more mature with larger fringe length, bigger fringe tortuosity, higher graphitization degrees and lower oxidation reactivity. • Saturated ester MB and unsaturated ester MC were chosen as additives. • Soot productions and flame temperatures were tested. • Nanostructure and nanoscale parameters of soot particles from IDF were studied. • Graphitization and oxidation reactivity of soot particles were investigated. • Effects of MB and MC additions on soot characteristics were discussed. [ABSTRACT FROM AUTHOR]

• Modified g-C 3 N 4 nanostructures was fabricated by a preorganization approach. • g-C 3 N 4 photocatalysts demonstrate improved degradation and hydrogen production. • Nanostructure engineering accelerates charge carrier dynamics. • Tunable band structure and high-performance solar photocatalysis are achieved. Pristine graphitic carbon nitride (g-C 3 N 4) suffers from poor photocatalytic activity due to its limited light adsorption, small specific surface area and feasible recombination of photogenerated charge carriers. One practical approach to solve the problem of low solar-to-hydrogen efficiency is nanostructuring the morphology of g-C 3 N 4 to enhance its light-harvesting property and boost the rate of charge-carrier transportation. Here, we present a strategy to optimize the textural properties and catalytic performance of g-C 3 N 4 via using oxamide (OA) as a chemical modifier in the precursor solution, which significantly make the light absorption edge shift from 440 to 650 nm. Moreover, the nanostructure of the resultant g-C 3 N 4 can be easily tuned with increasing the amount of oxamide. The morphological features of g-C 3 N 4 materials change from sheet-like structure to tubular structure, porous nanotube and eventually interconnected porous sheet. More interestingly, the unique g-C 3 N 4 nanostructure offers advantages of a broader solar absorption spectrum and accelerates charge carrier dynamics that are favorable for advancing photocatalytic performance. The findings provide insightful information that can be used to understand the structure-property relationship in g-C 3 N 4 nanostructures for improved solar-to-fuel conversion. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (AZIBs), with the merits of high safety, environmental friendliness, abundant resources, and competitive energy density are recognized as a promising secondary battery technology and are anticipated to be a great alternative to organic lithium-ion batteries (LIBs). However, the commercial application of AZIBs is severely hindered by intractable issues, including high desolvation barrier, sluggish ion transport kinetics, growth of zinc dendrite, and side reactions. Nowadays, cellulosic materials are frequently employed in the fabrication of advanced AZIBs, because of the intrinsically excellent hydrophilicity, strong mechanical strength, sufficient active groups, and unexhaustible production. In this paper, we start from reviewing the success and dilemma of organic LIBs, followed by introducing the next-generation power source of AZIBs. After summarizing the features of cellulose with great potential in advanced AZIBs, we comprehensively and logically analyze the applications and superiorities of cellulosic materials in AZIBs electrodes, separators, electrolytes, and binders with an in-depth perspective. Finally, a clear outlook is delivered for future development of cellulose in AZIBs. Hopefully, this review can offer a smooth avenue for future direction of AZIBs by means of cellulosic material design and structure optimization. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract α-Fe 2 O 3 nanoparticles with different sizes were successfully synthesized by a simple SDS-assisted grinding reaction and subsequent heating treatment process. Effects of calcination temperatures on crystal structure, optical and photocatalytic properties of the products were investigated by TG-DSC, FTIR, XRD, TEM, HRTEM, and UV–Vis techniques. Results showed that growth of the α-Fe 2 O 3 nanoparticles was very slow, and the average crystallite size gradually increased with increasing calcination temperatures. Optical measure and calculation showed that there is an increasing trend for the band gap with increase of calcination temperature. The α-Fe 2 O 3 nanoparticles obtained at 500 °C revealed higher photocatalytic degradation efficiency for MB than the other samples, attributing to the optimal value between transiting electrons and recombination of electron-hole pairs. Radical scavengers experiments implied that ·OH and e− played important roles in the photocatalytic process. The photodegradation time was greatly shortened, and the photocatalytic efficiency was further enhanced and raised to over 90% after adding H 2 O 2 , which is due to generation of a large number of the highly oxidative ·OH by photo-Fenton reaction. Highlights • α-Fe 2 O 3 nanoparticles were successfully synthesized by decomposing precursor. • Precursor was obtained by a simple SDS-assisted grinding reaction. • High photocatalytic efficiency of 99.6% was obtained for α-Fe 2 O 3 within 40 min. • It is due to generation of a large number of the ·OH by Photo-Fenton reaction. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mesoporous NiO/GNS composites were fabricated by in-situ thermal deposition. • Graphene matrix serves as an efficient conductive network for supercapacitor electrodes. • Graphene matrix offered accessible electroactive sites for electrochemical reactions. • The nanocomposites exhibited high performance as supercapacitor electrodes. Abstract Scholars have attached increasing attention to Graphene nanosheet (hereinafter referred to as GNS)-loaded transition metal oxide composites owing to the ability of attaching inorganic nanoparticles with better capacity and capacitance and better capacity than GNS of conductive polymer materials. A novel mesoporous structure of NiO nanoplates encapsulated in graphene matrix was synthesized and designed rationally. The composite composed of GNS and mesoporous NiO nanoplates can expand the approximate specific surface area of electrolyte. It has various advantages, such as good charge transport and short ion diffusion path. In addition, the interconnected graphene conducting network, as an adhesive, can maintain structural stability and promote charge transport by encapsulating mesoporous NiO nanoplates. The specific capacity is increased to 1050 F g−1 through the improved optimized NiO/GNS hybrid electrodes. This study provides a new idea for the design and manufacture of high performance transition metal oxide energy storage devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Using graphene as a conductive matrix, the homogeneous distribution of Co 3 O 4 nanoparticles was accomplished and volume changes in the nanoplates during charge–discharge process were effectively accommodated, resulting in the excellent electrochemical performance of the composites. The mesoporous structure of the Co 3 O 4 nanoparticles was suitable for the transfer of Ionic electrolyte by the electrochemical reaction. Co 3 O 4 /graphene nanocomposites are a candidate material for high-capacity, low-cost, and nontoxic electrode for supercapacitors. Highlights • Co 3 O 4 /graphene composites were prepared via an in situ thermal deposition method. • Graphene serves as an efficient conductive network for electrochemical reactions. • The nanocomposites exhibited high performance as supercapacitor electrodes. Abstract In situ synthesis of mesoporous Co 3 O 4 nanoparticles embedded in reduced graphene oxide nanosheets (GNSs) was implemented through coprecipitation method and pyrolytic process. In the charge-discharge process, electrolyte ions can fill with three-dimensional GNS matrix with connected pore network structures and mesoporous Co 3 O 4 nanoparticles with uniform nanoscale structures as double ion buffer reservoirs. The capacitance value of Co 3 O 4 /GNS nanocomposites is 1085.6 F g−1 at the current density of 2 A g−1 in 2 M KOH solution. The composite has good cyclic stability, and the maximum capacitance loss is only 17.3% in 10,000 successive cycles. [ABSTRACT FROM AUTHOR]

Two types of ternary metal oxides, MnCo 2 O 4.5 and MnNi 6 O 8 nanoparticles have been separately synthesized through chemical transformation from the corresponding bimetallic coordination polymer particles precursor under high-heating conditions. Series of electrochemical measurements are performed to examine the MnCo 2 O 4.5 and MnNi 6 O 8 electrodes, and the result shows that MnCo 2 O 4.5 structure, especially for Mn/Co-600, has much higher capacitance than that of MnNi 6 O 8 nanoparticles, indicating MnCo 2 O 4.5 electrode is more suitable for applying in neutral electrolyte system. The Mn/Co-600 electrode exhibits a specific capacitance of 158 F g −1 at 5 mV s −1 , good rate capability of 53.8% with a 20 times current density increase, good cycle performance (92.9% capacitance retention after 1000 cycles) and high power density (a specific power of 5760 W kg −1 at 4.0 A g −1 ) with low charge transfer resistance value of 1.8 Ω. [ABSTRACT FROM AUTHOR]

Amorphous core–shell CoO@C and Mn 3 O 4 @C composites have been synthesized by documenting a simple glucose–ethanol-assisted approach and characterized by SEM, TEM, X-ray diffraction, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Electrochemical measurements are performed to examine the CoO@C composites, and the result shows that CoO@C structure has much higher capacitance, higher energy and power density and better cycling performance than that of C/CoO hybrids. This improvement can be attributed to the nature of core–shell structure, which promotes fast Faradaic charging and discharging reaction and also minimizes both the ionic and electronic transportation distances and therefore improves the resulting electrode kinetic performance. [ABSTRACT FROM AUTHOR]

Abstract: Co3O4/graphene nanosheet (GNS) composites were synthesized via the in situ growth of mesoporous Co3O4 nanoparticles on graphene. The as-prepared Co3O4/GNS composites exhibited superior Li-ion battery performance and showed a large reversible capacity, excellent cycling, and good rate capability when used as an anode material in lithium ion batteries (LIBs). The uniform coating of Co3O4 around the graphene surface ensured tight electrical contact, resulting in a material with higher specific capacity and enhanced cycling performance compared with pure Co3O4 electrodes. The composites delivered a reversible capacity of 900mAhg−1 at a discharge current density of 100mAg−1 with good cycling ability. Moreover, the composites showed exceptional high-current charge–discharge performance, achieving 650mAhg−1 at a current density of 1000mAg−1. [Copyright &y& Elsevier]

Abstract: A MnO nanoparticle/graphene composite was prepared via in situ carbothermal reduction of Mn3O4 on the surface of graphene nanosheets. The formed MnO nanoparticles with diameters ranging from 20nm to 250nm integrated tightly with the graphene nanosheets. As anode material for lithium-ion batteries, the nanocomposite showed a high specific capacity of approximately 700mAhg−1 at 100mAg−1, excellent cyclic stability, and good rate capability. During the charge-discharge process, graphene nanosheets served as a three-dimensional conductive network for MnO nanoparticles. Furthermore, the detachment and agglomeration of MnO nanoparticles were effectively prevented due to the tight combination of MnO nanoparticles and graphene. [Copyright &y& Elsevier]

To better understand the occurrence state and characteristics of naturally formed TiO 2 in the environment, four types of different natural media were collected from nine areas distributed throughout five different provinces in China. For the first time, this study demonstrated that naturally formed TiO 2 nanoparticles are widely distributed in various media (soil solid, underground water, geogas and organisms) on the surface of the earth. With the help of a high-resolution transmission electron microscope (TEM), the morphology, chemical composition and crystal structure of TiO 2 nanoparticles in natural media were obtained. The characteristics of natural TiO 2 nanoparticles were found to be different from those of engineered TiO 2 nanoparticles, while natural TiO 2 nanoparticles in different media were found to have similar characteristics. In general, single naturally formed TiO 2 nanoparticles usually appear as complete or incomplete polygons, while aggregations of naturally formed TiO 2 nanoparticle are mostly irregular in shapes. The main growth stages of TiO 2 crystals in natural media were also investigated in this study. In brief, along with the crystal shapes of the TiO 2 particles changing from imperfect to perfect, the degree of crystallinity of the particles was also gradually improved. Furthermore, natural TiO 2 nanoparticles were found to always carry some amount of other elements related to the surrounding environment, resulting in a more complex composition. This phenomenon may contribute to the interpretation of elemental migration and ore prospecting to some degree, but the potential environmental hazards associated with TiO 2 nanoparticles may be enhanced as well. Unlabelled Image [ABSTRACT FROM AUTHOR]

• A composite photocatalyst of Ag 3 PO 4 particles decorated on modified crispy g-C 3 N 4 flake was fabricated. • Photocatalytic oxygen evolution over Z-scheme heterojunction is roughly 7-fold higher than that in Ag 3 PO 4. • Highly efficient oxygen-evolving performance is mainly attributed to accelerated interfacial charge transfer. • Surface modification and nitrogen atmosphere favor well-organized g-C 3 N 4 nanostructures and enhanced photocatalytic activity. Searching for highly efficient photocatalysts for water oxidation is the footstone for the development of overall water splitting systems and has been actively pursued. The construction of artificial Z-scheme heterojunction photocatalysts has been conclusively proven to be effective in boosting charge transport property and in improving the OER performance. Herein, Ag 3 PO 4 particles anchored on modified crispy g-C 3 N 4 flakes have been successfully fabricated. KOH-assisted surface modification of g-C 3 N 4 flakes and intimate interfacial contact favor the accelerated charge transfer and highly improved OER efficiency. Ultrafast spectroscopy results reveal that modified g-C 3 N 4 with crispy nanostructures possesses more trap-induced long-lived photogenerated holes, which are extremely helpful to combine with photo-generated electrons from the conduction band (CB) position of Ag 3 PO 4 via the specific Z-scheme configuration, leaving more holes in the valence band (VB) of Ag 3 PO 4 for the enhanced OER. Superb oxygen-evolving performance highlight the great promise of Z-scheme Ag 3 PO 4 -based heterojunctions in solar-driven photocatalytic water splitting. [ABSTRACT FROM AUTHOR]

• 1D CdS/2D Ti3C2 MXene Schottky heterojunction was successfully fabricated. • In situ constructed Schottky photocatalyst exhibits enhanced HER performance. • Ultrathin 2D MXene enhances light absorption and accelerates charge transport. • The specific Schottky interface is responsible for the improved HER activity. Benefiting from excellent metallic conductivity, full-spectrum solar energy absorption and rich active sites on the surface, atomically thin two-dimensional transition metal carbide (2D MXene) shows great promise in improving solar-to-hydrogen efficiency and has drawn intense interest in the field of photocatalysis. However, controllable construction of ultrathin 2D MXene-based heterojunction photocatalysts still remains a significant challenge. Herein, one-dimensional (1D) CdS nanorod/2D MXene nanosheet heterojunctions with well-defined nanostructures and strong interfacial coupling are fabricated by in situ assembling solvothermally-generated CdS nanorods on ultrathin Ti 3 C 2 MXene nanosheets. Due to their specific interface characteristics, 1D/2D Schottky heterojunction is capable of providing accelerated charge separation and a lower Schottky barrier for solar-driven hydrogen evolution from water splitting. As expected, the Schottky-based photocatalyst is 7-fold more active in the illuminated hydrogen evolution reaction (HER) than pristine CdS nanorods, implying the synergistic effects between n-type semiconductor CdS and highly conductive 2D Ti 3 C 2 MXene nanosheets. [ABSTRACT FROM AUTHOR]

• Nanoparticles in groundwater were investigated using TEM. • Nanoparticles with different contents of ore-forming elements can be grouped into three main types. • A relationship between metal-bearing nanoparticles and concealed orebodies was demonstrated. • Classification of ore-related nanoparticles was important for the detection of mineralization information. The characterization of nanoparticles in groundwater is recognized as an important tool that can be applied to mineral exploration. In this paper, we investigate the concealed orebodies of the Qujia gold deposit in the Jiaojia orefield of eastern China by analyzing ore-related nanoparticles in groundwater using transmission electron microscopy. The nanoparticles contain variable amounts of ore-related elements (e.g., Ag, Cu, Zn, La, Ce, Pb, Pt, and S). Some of these elements are rarely found in natural settings unrelated to orebodies or mineral extraction, but are strongly linked to concealed orebodies in the study area. These nanoparticles, which are diverse in their shapes, aggregated features, and degrees of crystallinity, can be grouped in terms of composition as: (i) native metal nanoparticles, (ii) metal-based nanoparticles, and (iii) carrier nanoparticles associated with trace elements. We propose that these three main types of nanoparticles enable the efficient transport of ore-forming elements in groundwater. The results of this study provide insights into the migratory behaviour of ore-related nanoparticles in groundwater, and our methods could be applied for detecting deep-seated mineral deposits. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C 3 N 4) is sprouted as an efficient and cost-effective visible-light-responsive photocatalyst for yielding hydrogen from water splitting. However, a brisk recombination of light-induced electron-hole (e− - h+) pairs in the bulk g-C 3 N 4 effectuate poor quantum efficiency in the hydrogen evolution reaction (HER). The shuttle redox mediator manifests ample potential in accelerating photo-induced carrier segregation and in boosting charge transport in the HER. Here, we report that exploiting Ag/Ag(I) and Fe(III)/Fe(II) shuttle redox mediators, the hydrogen-evolving rate of the aforementioned g-C 3 N 4 nanosheets can reach 3213.3 μmol g−1 h−1 under visible-light irradiation, which is eight times higher than that of pure g-C 3 N 4 (404.82 μmol g−1 h−1). The effective coupling between a hydrogen-evolving catalyst and appropriate shuttle redox mediators significantly improves the HER-photocatalytic performance of native g-C 3 N 4 nanosheets. Density functional theory calculations show that the presence of Ag/Ag(I) and Fe(III)/Fe(II) shuttle redox mediators can effectively promote H atom adsorption and facilitate a H 2 O reduction reaction. This work envisages a new and deft approach for contriving high-performance g–C 3 N 4 –based photocatalysts for highly efficient solar-to-fuel conversion. • Ag/Ag(I) and Fe(III)/Fe(II) shuttle redox were loaded on the surface of g-C 3 N 4. • The modified g-C 3 N 4 showed excellent photocatalytic H 2 activity and chemical stability. • Double shuttle redox on the g-C 3 N 4 boost the separation of photoexcited charges. [ABSTRACT FROM AUTHOR]

• 2D g-C 3 N 4 nanosheet was fabricated by the supramolecular assembly approach. • Assembled 2D g-C 3 N 4 photocatalyst demonstrates enhanced HER performance. • 2D nanostructure accelerates charge transport and solar-to-hydrogen efficiency. • Ultrafast spectroscopy reveals charge carrier dynamics in 2D g-C 3 N 4 nanosheets. Two-dimensional graphitic carbon nitride (2D g-C 3 N 4) nanostructures have been the focus of substantial research interest recently owing to their promising photoactive properties for use in solar-to-fuel conversion. However, the synthesis of 2D g-C 3 N 4 nanomaterials remains a significant challenge. Here we successfully synthesized 2D g-C 3 N 4 nanosheets via a supramolecular chemistry approach. 2D g-C 3 N 4 nanostructures not only enhance the visible light-harvesting property but also provide more catalytic sites for improved hydrogen evolution reaction (HER). More importantly, we describe experimental findings concerning the dynamics of charge and energy transfer by using ultrafast spectroscopy in combination with in-situ electron spin resonance (ESR) characterization. The mechanistic investigation reveals that the introduction of a benzene-substituted melamine motif can remarkably accelerate the electron-hole separation and suppress the recombination of photogenerated charge carriers. The carrier separation dynamics is expected to be tailored by engineering the surface and morphology of g-C 3 N 4 , which favors enhanced solar photocatalytic HER efficiency. [ABSTRACT FROM AUTHOR]

• A facile in situ synthesis of well-dispersed reduced graphene oxide-phenol formaldehyde composites (GPF). • Graphene could act as an enhanced radical scavenger in the resin matrix under the gamma irradiation environment. • Graphene could maintain the anti-corrosion properties of GPF under the gamma irradiation environment. As a category of long-term protective coating, phenol formaldehyde (PF) has been extensively applied in the nuclear industry. However, PF might emerge adverse degradation processes under the γ ray irradiation environment, which greatly restricts its further applications as the highly-efficient protective coatings. For the sake of addressing this issue, herein, a novel phenol noncovalent modified graphene oxide/phenol formaldehyde nanocomposite (GPF) has been constructed via in situ guiding phenol formaldehyde micromolecules format on the well-dispersed graphene oxide surface. Electron spin resonance and electrochemical tests intensively demonstrate that the highly dispersed graphene could act as an enhanced radical scavenger and retain the corrosion resistance properties for the GPF composites under the gamma irradiation environment. [ABSTRACT FROM AUTHOR]