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In the field of robot thermosensitive touch recognition systems, it is a major challenge to achieve high thermal conductivity and adhesion properties simultaneously in thermosensitive touch sensors to improve their sensitivity. To address this challenge, this study synthesized a copolymer of polydimethylsiloxane-co-poly([[(butylamino)carbonyl]oxy]ethylester) (PDMSPBA) using UV light polymerization. Then, a core–shell LABN filler was prepared using the principle of electronic hole coordination by combining boron nitride (BN) particles with liquid alloy (LA). The LABN core–shell structured filler was introduced into the PDMSPBA copolymer matrix to prepare PDMSPBA/LABN composite material. The LABN core–shell structure can reduce the distance of phonon transfer inside the composite material and promote the formation of a continuous heat channel. A series of tests showed that the thermal conductivity of PDMSPBA/LABN composite material was 3.75 W m−1 K−1, the electrical conductivity value was 10–6–10–8 S/m, and the surface adhesion was 1.23 × 104 N/m2. Most importantly, the PDMSPBA/LABN composite material was used as the core thermal interface material in the robot thermosensitive touch recognition system. Surprisingly, this intelligent touch recognition system can distinguish rock types in the dark within a specific range using the PDMSPBA/LABN composite material. In summary, the PDMSPBA/LABN composite material has great potential for application in the field of tactile perception of mining robots. [ABSTRACT FROM AUTHOR]

In this work, high temperature resistant materials based on waste electrical porcelain were prepared successfully by pressureless sintering method using waste electrical porcelain with different particle sizes, flint clay and dolomite as raw materials. Effects of sintering temperature and different amounts of flint clay on the properties of the prepared high temperature resistant materials were investigated. The analysis of XRD suggested that the temperature promoted the calcium aluminum silicate → gehlenite → anorthite phases transformation, which can also be proved from SEM images. The mechanical properties and volume stability of materials were improved by the formation of a large amount of interwoven plate-like anorthite. Besides, excessive sintering temperature (1300 °C) had adverse effects on microstructure and mechanical properties. The appropriate amount of flint clay additions led to more plate-like anorthite productions. With 30 wt% addition of flint clay, the sample exhibited the optimum comprehensive performance after sintering at 1250 °C showing the highest flexural and compressive strengths of 32.83 MPa and 89.59 MPa. The bulk density and apparent porosity of samples were 2.21 g/cm3 and 3.27%, respectively. This study provides an experimental basis for the large-scale high-value utilization and recycling of waste electric porcelain. [ABSTRACT FROM AUTHOR]

Prosthetic joint infection (PJI) is a prevalent and severe complication characterized by high diagnostic challenges. Currently, a unified diagnostic standard incorporating both computed tomography (CT) images and numerical text data for PJI remains unestablished, owing to the substantial noise in CT images and the disparity in data volume between CT images and text data. This study introduces a diagnostic method, HGT, based on deep learning and multimodal techniques. It effectively merges features from CT scan images and patients' numerical text data via a Unidirectional Selective Attention (USA) mechanism and a graph convolutional network (GCN)-based Feature Fusion network. We evaluated the proposed method on a custom-built multimodal PJI dataset, assessing its performance through ablation experiments and interpretability evaluations. Our method achieved an accuracy (ACC) of 91.4% and an area under the curve (AUC) of 95.9%, outperforming recent multimodal approaches by 2.9% in ACC and 2.2% in AUC, with a parameter count of only 68 M. Notably, the interpretability results highlighted our model's strong focus and localization capabilities at lesion sites. This proposed method could provide clinicians with additional diagnostic tools to enhance accuracy and efficiency in clinical practice. [ABSTRACT FROM AUTHOR]

Photocatalysis coupled with sulfate radical-based advanced oxidation process (SR-AOPs) is an efficient strategy to enhance the degradation efficiency of organic pollution. Herein, a Z-scheme CuFe 2 O 4 /MnO 2 composite catalyst was successfully fabricated by the hydrothermal method. A series of characterizations demonstrated that the higher CuFe 2 O 4 particle dispersion and larger BET surface area of CuFe 2 O 4 /MnO 2 catalyst contributed to a high catalytic activity toward the phenol removal compared with pure CuFe 2 O 4. The effects of catalyst concentration, pH, and peroxymonosulfate (PMS) concentration were studied according to the Box-Behnken Design (BBD) method. The results indicated that 100 mg/L 100 mL phenol could be degraded completely at 0.5 g/L CuFe 2 O 4 /MnO 2 catalyst, pH = 4.8 and 0.5 mM PMS within 30 min. Moreover, the excellent reusability and stability of CuFe 2 O 4 /MnO 2 were indicated by the results of recycling degradation and ion leaching test. The free radical quenching experiments and electron spin resonance (ESR) confirmed that h+, SO 4 •-, and •OH were the main reaction species for phenol oxidation. Based on the results of gas chromatography-mass spectrometry (GC-MS) and ion chromatography, the degradation pathway of phenol was proposed, and the toxicity of phenol degradation intermediates was evaluated. This work may provide new insights into the design of heterojunction photocatalysts for PMS activation to remove organic pollutants. • The Z-scheme CuFe2O4/MnO2 heterojunction was constructed via hydrothermal method. • The photocatalytic coupled with SR-AOPs significantly improves the removal efficiency of phenol. • The h+, SO4.•-, and •OH were the main reaction species for phenol oxidation. • The optimization operation of removal phenol according to RSM based on BBD. • The degradation intermediates of phenol were evaluated toxicity analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient CuHCF/C electrode was prepared for Cu2+ removal by CDI. • CuHCF/C achieved high Cu2+ adsorption capacity of 134.47 mg g−1 at low applied voltage of 0.8 V. • CuHCF/C manifested excellent Cu2+ selectivity in multi-ion coexisting solution. • The mechanism of removing Cu2+ by Faradaic pseudocapacitance was explained. The efficient capture of copper ions (Cu2+) in wastewater has dual significance in pollution control and resource recovery. Prussian blue analog (PBA)-based pseudocapacitive materials with open frameworks and abundant metal sites have attracted considerable attention as capacitive deionization (CDI) electrodes for copper removal. In this study, the efficiency of copper hexacyanoferrate (CuHCF) as CDI electrode for Cu2+ treating was evaluated for the first time upon the successful synthesis of copper hexacyanoferrate/carbon sheet combination (CuHCF/C) by introducing carbon sheet as conductive substrate. CuHCF/C exhibited significant pseudocapacitance and high specific capacitance (52.92 F g−1) through the intercalation, deintercalation, and coupling of Cu+/Cu2+ and Fe2+/Fe3+ redox pairs. At 0.8 an applied voltage and CuSO 4 feed liquid concentration of 100 mg L−1, the salt adsorption capacity was 134.47 mg g−1 higher than those of most reported electrodes. Moreover, CuHCF/C demonstrated excellent Cu2+ selectivity in multi-ion coexisting solutions and in actual wastewater experiments. Density functional theory (DFT) calculations were employed to elucidate the mechanism. This study not only reveals the essence of Cu2+ deionization by PBAs pseudocapacitance with promising potential applications but also provides a new strategy for selecting efficient CDI electrodes for Cu2+ removal. [ABSTRACT FROM AUTHOR]

Research on perovskites has grown exponentially in the past decade due to the potential of methyl ammonium lead iodide in photovoltaics. Although these devices have achieved remarkable and competitive power conversion efficiency, concerns have been raised regarding the toxicity of lead and its impact on scaling up the technology. Eliminating lead while conserving the performance of photovoltaic devices is a great challenge. To achieve this goal, the research has been expanded to thousands of compounds with similar or loosely related crystal structures and compositions. Some materials are "re-discovered", and some are yet unexplored, but predictions suggest that their potential applications may go beyond photovoltaics, for example, spintronics, photodetection, photocatalysis, and many other areas. This short review aims to present the classification, some current mapping strategies, and advances of lead-free halide double perovskites, their derivatives, lead-free perovskitoid, and low-dimensional related crystals. [ABSTRACT FROM AUTHOR]

Solution-based deposition, with its simplicity and possibility for upscaling through printing, is a promising process for low-cost electronics. Metal oxide semiconductor devices, especially indium oxide with its excellent electrical properties, offer high performance compared to amorphous Si-based rivals, and with a form factor conducive to flexible and wearable electronics. Here, rectifying diodes based on an amorphous spin-coated indium oxide are fabricated for high-speed applications. We report a solution-processed diode approaching the UHF range, based on indium oxide, with aluminum and gold as the electrodes. The device was spin-coated from a precursor material and configured into a half-wave rectifier. The J – V and frequency behavior of the diodes were studied, and the material composition of the diode was investigated by X-ray photoemission spectroscopy (XPS). The 3-dB point was found to be over 700 MHz. The results are promising for the development of autonomously powered wireless Internet-of-Things systems based on scalable, low-cost processes. [ABSTRACT FROM AUTHOR]

The discovery of novel polymeric materials with variable heat transport properties could revolutionize the utilization and manipulation of thermal energy to keep devices working optimally. Here, we synthesized a poly-1-butyl-5-((4-(phenyldiazenyl)phenoxy)methyl)2-ethyl-2,4,4-trimethylpentanedioate (AzoBmapolymer) containing photoisomerization's groups through reversible addition-fragmentation chain transfer polymerization. Firstly, using a thermal conductivity (TC)-measuring instrument, we demonstrate the TC of photoresponsive AzoBmapolymer that reversibly switches between low (0.13 ± 0.02 Wm−1 K−1) and high (0.24 ± 0.02 Wm−1 K−1) states. And surprisingly, the 84.6% change of TC was achieved by the modulation of the AzoBmapolymer containing photoisomerization's groups through green and ultraviolet photoirradiation. What is more, our synthesized photosensitive AzoBmapolymer is capable of TC transition within 7 s controlled by photoirradiation, and its photoregulated TC transition rate is dozens or hundreds of times higher than that driven by magnetic field molecular orientation (0.17 h), electrochemical oxygenation (0.5 h), or temperature modulation (1 h). Theoretically, the photoisomerization's groups of AzoBmapolymer can lead to different spatial configurations of macromolecules. Meanwhile, this conformational transition results in a change in the π–π stacking (dπ–π) spatial configuration and an amorphous-to-crystal transition. More importantly, X-ray diffraction, crosspolarized optical microscopy, and TC-measuring instrument jointly demonstrate that photoirradiation reversibly change the thermophysical properties of AzoBmapolymer phonon transport. In other words, this result illustrates a powerful manipulation of the thermophysical properties of the polymers by photoirradiation. The AzoBmapolymer could complement traditional metal heat transfer materials used in applications; for instance, heat exchangers, electronic packaging, and heat sink. [ABSTRACT FROM AUTHOR]

The tremendous growth of disposable electrode-based portable devices for point-of-care testing requires mass production of disposable electrodes in a low-cost and sustainable manner. Here, we demonstrate a green route for the conversion of biomass lignin, patterning, and reduction of the lignin-derived graphene electrodes by sequential laser lithography, water lift-off and sodium borohydride (NaBH 4) treatment, and their use for electrochemical lactate biosensors. Energy-saving and localized laser lithography converted the aromatic ring-rich lignin into porous laser-induced graphene (LIG). The conductivity and attachment of the LIG to the substrate were optimized in a factorial experiment with laser power and scan speed as variables. Characterization results revealed the conversion of partial heteroatoms (e.g., Na, S, O) into granular inorganic compounds on the LIG surface under laser treatment. Water was used as an eco-friendly solvent for the patterning of the LIG (P-LIG) by a lift-off process, where the inorganic residues and un-reacted lignin were dissolved, exposing the macro-/micro-pores in the P-LIG. NaBH 4 induced a reduction of the P-LIG (P-rLIG) resulting in improved electrochemical kinetics with lower charge transfer resistance (27.3 Ω) compared to the LIG (248.1 Ω) and the P-LIG (61.4 Ω). The porous P-rLIG served as a 3D electrode for the deposition of Prussian blue and lactate oxidase for disposable electrochemical lactate biosensors, delivering a good analytical performance towards lactate detection with a linear range up to 16 mM and a high sensitivity (1.21 μA mM−1). These lignin-derived disposable electrodes, utilizing renewable resources together with low-energy consumption fabrication and patterning, may contribute to the sustainable manufacturing of biosensors for point-of-care and point-of-use applications. [ABSTRACT FROM AUTHOR]

Mullite–cordierite ceramic saggar is a necessary consumable material used in the synthesis process of LiCoO2 that is easily eroded during application. In our study, we systematically investigated the characteristics and surface corrosion behavior of waste saggar samples. We divided the cross sections of waste saggar into the attached layer, hardened layer, permeability layer, and matrix layer. Then, we examined the high-temperature solid-state reactions between saggar powder and lithium carbonate or cobalt oxide to identify erosion reactants correlating with an increase in the number of recycled saggars. The results of time-of-flight secondary ion mass spectrometric analysis (TOF-SIMS) prove that the maximum erosion penetration of lithium can reach 2 mm. However, our morphology and elemental distribution analysis results show that the erosion penetration of cobalt was only 200 μm. When enough lithium carbonate reacted, lithium aluminate and lithium silicate were the main phases. Our X-ray computed tomography (X-ray CT) analysis results show that the change in phase volume before and after the reaction, including the generation of oxygen and carbon dioxide gas, led to the internal crack expansion of the material–saggar interface. Our results can contribute to improving saggar and upgrading waste saggar utilization technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe, Cu co-doped promotes electron transfer of ORR. • Fe, Cu co-doped adjust d-band of elements. • Fe, Cu act synergistically through redox coupling. • FeCu@CN shows the remarkable stability in application of MFC. Air cathode microbial fuel cell (AC-MFC) cannot be used on a large scale because of its low oxygen reduction reaction (ORR) efficiency. Despite the fact that bimetallic catalysts can greatly enhance the oxygen reduction rate by regulating the electronic structure of the active site, the flaws of insufficient exposure of the active site and easy metal agglomeration limit its catalytic activity. Herein, we report on the preparation of a stable heteroatomic substrate using a copper material organic framework as a precursor, covered by Fe-based active sites. As a result of dipole-dipole interactions, the reduced product Fe2+ forms a weak Fe-O surface that is conducive to the adsorption of active substances. The presence of Fe0 enhances the electrical conductivity of the catalytic, thus promoting ORR efficiency. Through redox coupling, the D-band center of Fe at FeCu@CN is optimized and brought close to the Fermi level to facilitate electron transfer. Notably, FeCu@CN demonstrates a superior power density of 2796.23 ± 278.58 mW m−3, far exceeding that of Pt/C (1363.93 ± 102.56 mW m−3), in the application of microbial fuel cells (MFCs). Meanwhile, the MFC-loaded FeCu@CN maintains excellent stability and outstanding output voltage after 1000 h, which provides feasibility for large-scale application. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) suffer from significant nonradiative recombination at perovskite/charge transport layer heterojunction, seriously limiting their power conversion efficiencies. Herein, solution‐processed chromium multioxide (CrOx) is judiciously selected to construct a MAPbI3/CrOx/Spiro‐OMeTAD hole‐selective heterojunction. It is demonstrated that the inserted CrOx not only effectively reduces defect sites via redox shuttle at perovskite contact, but also decreases valence band maximum (VBM)‐HOMO offset between perovskite and Spiro‐OMeTAD. This will diminish thermionic losses for collecting holes and thus promote charge transport across the heterojunction, suppressing both defect‐assisted recombination and interface carrier recombination. As a result, a remarkable improvement of 21.21% efficiency with excellent device stability is achieved compared to 18.46% of the control device, which is among the highest efficiencies for polycrystalline MAPbI3 based n–i–p planar PSCs reported to date. These findings of this work provide new insights into novel charge‐selective heterojunctions for further enhancing efficiency and stability of PSCs. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI) is a high-performance, low-energy consumption, and environmentally friendly water treatment technology with a broad application prospect in heavy metal removal. Selecting electrode materials with high capacitance and low resistance is essential for improving CDI's desalting efficiency. This article discusses the utilization of sugarcane bagasse (C-N-X) and the production procedures of CDI materials. The unique 3D cross-linked structure of C-N-X provides excellent mass transfer properties and significant advantages in capacitance and conductivity. The results of X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared Spectrometer (FTIR) show that bagasse biochar with graphene-like structure and abundant functional groups provides active sites for Cu2+ removal. In this paper, C-N-X is first used as CDI electrode material to remove Cu2+. Electrochemical tests show that the specific capacitance of C-N-X is still stable at about 47 F g−1, and the removal capacity of Cu2+ (25 mg L−1) reaches 66.79 mg g−1 within 4 h after 700 cycles. The experimental results and DFT calculations confirm the adsorption selectivity of C-N-700 for Cu2+. [Display omitted] [ABSTRACT FROM AUTHOR]

• With a small applied potential, we can create large concentration of S vacancies in amorphous MoS 2 structure when deposited on semimetal CoMoP 2. • As electrocatalyst for hydrogen evolution, the current density of vacancy-rich MoS 2 is increased by 221% at a given overpotential. • Both theoretical and experiment confirmed the formation energy of S vacancies can decreased significantly by using CoMoP 2 as supporting material. The presence of elemental vacancies in materials are inevitable according to statistical thermodynamics, which will decide the chemical and physical properties of the investigated system. However, the controlled manipulation of vacancies for specific applications is a challenge. Here we report a facile method for creating large concentrations of S vacancies in the inert basal plane of MoS 2 supported on semimetal CoMoP 2. With a small applied potential, S atoms can be removed in the form of H 2 S due to the optimized free energy of formation. The existence of vacancies favors electron injection from the electrode to the active site by decreasing the contact resistance. As a consequence, the catalytic current is increased by 221% with the vacancy-rich MoS 2 as electrocatalyst for hydrogen evolution reaction (HER). A small overpotential of 75 mV is needed to deliver a current density of 10 mA cm−2, which is considered among the best values achieved for MoS 2. It is envisaged that this work may provide a new strategy for utilizing the semimetal phase for structuring MoS 2 into a multi-functional material. [ABSTRACT FROM AUTHOR]

The metal-free carbon-based catalyst with low cost and high oxygen reduction reaction (ORR) activity is urgently desired to satisfy the demands of microbial fuel cells (MFCs). However, it is still a great challenge to develop a facile and feasible strategy to construct efficient active sites of heteroatom doping for carbon-based electrocatalyst. Herein, we report a strategy based on an ammonium fluoride (NH 4 F) gas-steamed metal-organic frameworks (MOFs) to heighten structural defects and density of N, F active sites of metal-free catalyst. Oxygen temperature-programmed deposition and density functional theory results confirm that the NH 4 F gas-steamed process greatly enhances the adsorption affinity of O 2 and oxygen intermediates on the catalysts. The resulted N and F co-doped porous carbon cage (FNC-15) demonstrates outstanding ORR catalytic activity and long-term stability in alkaline and neutral electrolytes. This work proposes a facile and efficient in situ gas-steamed strategy to develop metal-free cathode catalysts with superior performance. [Display omitted] • NH 4 F gas-steamed strategy introduce defects and N, F active sites within catalysts. • Defect sites enhance the oxygen molecules adsorption affinity of catalysts. • Remarkably enhanced ORR catalytic activity and stability. • The metal-free FNC-15 exhibits superior performance in microbial fuel cell. [ABSTRACT FROM AUTHOR]

The oxygen reduction reaction (ORR) kinetics are well known to strongly rely on the activives of electrocatalysts. Herein, a Fe-N-doped porous carbon-based electrocatalyst combined with zinc (Zn) -based metal-organic frameworks (MOFs) (Fe x -N@MOF) was designed and successfully fabricated via a facile process combined immersion doping and pyrolysis. By controlling the formation of Fe 3 C, the physical structure of porous carbon was significantly altered, and the active chemical sites of Fe species can be formed to catalyze ORR. The uniform N-doped three-dimensional interpenetrating network structure yielded a high surface area. Both Fe 3 C and Fe-N x could offer an abundance of active sites and thus promoted Fe 0.05 -N@MOF to exhibit high ORR activity in alkaline, neutral and acid electrolytes. Fe 0.05 -N@MOF showed extraordinary stability and methanol tolerance under a varied pH range conditions, it could be applied as cathode electrocatalyst in different fuel cells such as Zn-air fuel cell (ZFC), microbial fuel cells (MFCs), as well as direct methanol fuel cell (DMFC). Fe 0.05 -N@MOF is a promising material to replace Pt-based electrocatalysts as non-precious metal catalysts. [Display omitted] • The synergistic catalysis of Fe-N x and Fe 3 C on oxygen reduction reaction. • The transformation of carbon spheres to nanotubes was regulated by Fe species. • High electrocatalytic activity in alkaline, neutral and acidic media. • As cathode catalyst was applied to the various fuel cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co/Fe co-doped ZIF-8 derived porous carbon for CDI removal of Cu2+ ions. • A stable carbon cage encapsulated a porous carbon structure. • CoFe-NC has better selectivity for Cu2+ ions. • CoFe-NC shows higher electrosorption capacity in application of CDI. Due to a threat to human life from heavy metal ions pollution, unprecedented interest has been gained in the development of water purification technologies. Here, we explore another new approach to exploit a prospective carbon material for removing copper ions from aqueous solution based on rapid and easy capacitive deionization (CDI). Reasonable carbon materials modification with ideal composition and improved morphological structure is essential to additionally optimize the capabilities of CDI. We prepared a nitrogen-rich hierarchically porous carbon composites (CoFe-NC) with uniform cobalt (Co) and iron (Fe) doped metal in carbon skeleton by a simple impregnation and pyrolysis method, derived from zeolitic imidazolate framework-8, to use as highly effective CDI electrode for copper ions removal. The addition of Fe can facilitate the uniform dispersion of metals, and enable the formation of a stable carbon cage after pyrolysis. It can sufficiently expose active sites of the electrode materials and promote interfacial charge transfer, thus improving CDI electrosorption efficiency. CoFe-NC composites electrode can achieve outstanding deionization capacity (91.31 mg g−1) in 25 mg L−1 CuSO 4 solution. The carbon cage structure of CoFe-NC not only prevents aggregation of metals and avoids destruction of rich multistage pore system by pyrolysis, but also induces a faster ions transport rate. In addition, density functional theory calculations demonstrated that the co-doping of Co and Fe can remarkably increase the adsorption energies of Cu2+ ions, leading to excellent selectivity, which indicates that CoFe-NC composites can be a desired CDI electrode material. [ABSTRACT FROM AUTHOR]

Cathode electrocatalyst is quite critical to realize the application of microbial fuel cells (MFCs). Perovskite oxides have been considered as potential MFCs cathode catalysts to replace Pt/C. Herein, Cu-doped perovskite oxide with a stable porous structure and excellent conductivity was successfully prepared through a sol-gel method. Due to the incorporation of Cu, CaFe 0.9 Cu 0.1 O 3 has more micropores and a larger surface area, which are more conducive to contact with oxygen. Doping Cu resulted in more Fe3+ in B-site and thus enhanced its binding capability to oxygen molecules. The data from electrochemical test demonstrated that the as-prepared catalyst has good conductivity, high stability, and excellent ORR properties. Compared with Pt/C catalyst, CaFe 0.9 Cu 0.1 O 3 exhibits a lower overpotential, which had an onset potential of 0.195 V and a half-wave potential of −0.224 V, respectively. CaFe 0.9 Cu 0.1 O 3 displays an outstanding four-electron pathway for ORR mechanism and demonstrates superiors corrosion resistance and stability. The MFC with CaFe 0.9 Cu 0.1 O 3 has a greater maximum power density (1090 mW m−3) rather than that of Pt/C cathode (970 mW m−3). This work demonstrated CaFe 0.9 Cu 0.1 O 3 is an economic and efficient cathodic catalyst for MFCs. • Cu-doped double B-site perovskite forms microporous structure. • Cu promotes the combination of Fe–O and O. • CaFe 0.9 Cu 0.1 O 3 shows outstanding and highly stable ORR catalytic performance. • CaFe 0.9 Cu 0.1 O 3 can be used as a highly efficient cathode catalyst in MFCs. [ABSTRACT FROM AUTHOR]

Exploiting a facile way to synthesize low-cost and high-performance oxygen reduction reaction (ORR) catalysts is a core issue in microbial fuel cells (MFCs). Hence, a facile and extensible method has been developed to prepare efficient ORR catalysts by using robust UiO-66 as a precursor, modified with melamine and trithiocyanuric via the impregnation method. Benefiting from the hierarchical structure of UiO-66, the NS@UiO-66 has excellent stability, more active sites and improved mass transfer. Significantly, the half-wave potential and the current density of the NS@UiO-66 are 0.546 V vs. RHE and 6.19 mA cm−2 respectively, which is better than that of benchmark Pt/C in neutral conditions. Furthermore, the power density of MFCs assembled with the NS@UiO-66 catalyst is 318.6 ± 2.15 mW m−2. The density functional theory calculation demonstrates that the reaction barrier can be reduced effectively for accelerating the ORR process through the synergistic effect of N and S. The NS@UiO-66, as an ideal candidate to substitute for the commercial Pt/C counterpart, is expected to promote the scaling-up production and application of MFCs due to low-cost elements doping and facilely synthetic method. [Display omitted] • A facile synthesis way for preparing NS@UiO-66 porous carbon is proposed. • UiO-66 is a stable platform exposing more active sites and boosting mass transfer. • N, S co-doping induces charge redistribution and reduces the activation barrier. • The stable NS@UiO-66 shows great ORR property and application prospects in MFCs. [ABSTRACT FROM AUTHOR]

Abstract: Nano-crystalline diamond (NCD)-coated surfaces were efficiently functionalized with bone morphogenetic protein-2 (BMP-2) by means of physisorption. Due to their randomly oriented texture, NCD-coated surfaces appear to bind complex molecules firmly. Applying various highly sensitive analytical methods, the interaction was found extremely stable. The strength of the experimentally measured adherence between BMP-2 and NCD was further corroborated by theoretical calculations. Oxygen treatment rendered NCD hydrophilic by the appearance of surface oxygen containing groups. This particular NCD surface exhibited even higher binding energies towards BMP-2 than the hydrophobic surface, and this surface was also favoured by cultured cells. Most importantly in this context, bound BMP-2 was found fully active. When cultured on BMP-2-treated NCD, osteosarcoma cells strongly up-regulated alkaline phosphatase, a specific marker for osteogenic differentiation. Hence, this simple method will allow generating highly versatile surfaces with complex biomimetic coatings, essentials for novel medical devices and implants as well as for innovative scaffolds in tissue engineering. [Copyright &y& Elsevier]

Stable perovskite oxide is considered as a potential cathode for microbial fuel cells (MFCs). Herein, Zn is used as an effective element to modify the micro-structure and oxygen vacancy of perovskite to be a novel cathode catalyst. Physical characterizations show that due to partial volatilization at high temperature of Zn, perovskite forms hierarchically porous structures. Moreover, Zn is precipitated in electrochemical reaction to generate Zn vacancy in situ; thus, the active center of Fe has a superior interaction with oxygen-containing species, promoting the production of oxygen vacancy and forms a mixed valence state of Fe2+/Fe3+. The Zn-doped perovskite material CaFe 0·7 Zn 0·3 O 3 exhibits remarkable oxygen reduction reaction (ORR) performances with outstanding onset potential (0.194 V vs. Ag/AgCl) and half-wave potential (−0.219 V vs. Ag/AgCl) under alkaline condition, which is better than Pt/C catalyst. Besides, CaFe 0·7 Zn 0·3 O 3 shows an excellent four-electron pathway of ORR mechanism with remarkable corrosion resistance and stability, which enables a more reliable cathode electrocatalyst. The maximum power density of CaFe 0·7 Zn 0·3 O 3 (892.10 ± 90.79 mW m−3) testing on microbial fuel cell is comparable to the maximum power density (1012.86 ± 84.03 mW m−3) of Pt/C. The findings of this work provide the feasibility of exploring inexpensive and high-performance cathode catalyst. Image 1 • Zn-doped CaFeO 3 promotes mesoporous formation. • The incorporation of Zn creates more oxygen vacancies. • CaFe 0·7 Zn 0·3 O 3 shows the remarkable catalytic activity and stability during ORR. • Applying as the cathode catalyst in microbial fuel cells. [ABSTRACT FROM AUTHOR]

As a promising energy conversion equipment, the performance of microbial fuel cell (MFC) is affected by slow kinetics of oxygen reduction reaction (ORR). It is of great significance to explore electrocatalysts with high activity for sustainable energy applications. Herein, we synthesize the in-situ grown carbon nanotubes decorated electrocatalyst derived from copper-based metal organic frameworks (MOFs) co-doped with cobalt and nitrogen (CuCo@NCNTs) through straightforward immersion and pyrolysis process. The carbon nanotubes produced by metallic cobalt and high-activity bimetallic active sites formed by nitrogen doping enable CuCo@NCNTs to have the best oxygen reduction reaction (ORR) performance in alkaline electrolyte, with limit current density of 5.88 mA cm−2 and onset potential of 0.91 V (vs. RHE). Moreover, CuCo@NCNTs nanocomposite exhibits obvious antibacterial activity, and inhibiting the biofilm on cathode surface in antibacterial test and biomass quantification. The maximum power density (2757 mW m−3) of MFC modified with CuCo@NCNTs is even higher than Pt/C catalyst (2313 mW m−3). In short, CuCo@NCNTs nanocomposite can be an alternative cathode catalyst for MFC. Image 1 • Carbon nanotubes grew in situ on carbon precursors. • Abundant active nitrogen components and bimetal active sites. • High catalytic activity and inhibition of biofilm formation. • As cathode catalyst applied to the air-microbial fuel cell. [ABSTRACT FROM AUTHOR]

Van der Waals heterostructures combining hexagonal boron nitride (h-BN) and graphene offer many potential advantages, but remain difficult to produce as continuous films over large areas. In particular, the growth of h-BN on graphene has proven to be challenging due to the inertness of the graphene surface. Here we exploit a scalable molecular beam epitaxy based method to allow both the h-BN and graphene to form in a stacked heterostructure in the favorable growth environment provided by a Ni(111) substrate. This involves first saturating a Ni film on MgO(111) with C, growing h-BN on the exposed metal surface, and precipitating the C back to the h-BN/Ni interface to form graphene. The resulting laterally continuous heterostructure is composed of a top layer of few-layer thick h-BN on an intermediate few-layer thick graphene, lying on top of Ni/MgO(111). Examinations by synchrotron-based grazing incidence diffraction, X-ray photoemission spectroscopy, and UV-Raman spectroscopy reveal that while the h-BN is relaxed, the lattice constant of graphene is significantly reduced, likely due to nitrogen doping. These results illustrate a different pathway for the production of h-BN/graphene heterostructures, and open a new perspective for the large-area preparation of heterosystems combining graphene and other 2D or 3D materials. [ABSTRACT FROM AUTHOR]