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Direct ink writing (DIW) offers significant advantages for efficient manufacturing of complex ceramic composite components. However, the mechanical properties of short carbon fiber-reinforced ceramic composites fabricated by DIW technology were not ideal, mainly be ascribed to the absence of a suitable coating on the fiber as an interface. In this work, C sf /ZrB 2 green bodies were printed by an optimized extrusion process using pyrolytic carbon-coated short carbon fibers (C sf). High-performance C sf /ZrB 2 –SiC composites were obtained through the infiltration and pyrolysis of SiC precursor six times. With increasing C sf content, the dimensional deviations decreased and the mechanical properties increased. When the C sf content was 30 vol%, the dimensional deviation of the C sf /ZrB 2 –SiC composite was less than −0.5 % in the X and Y directions and about −2 % in the Z direction. A marked increase in the flexural strength and fracture toughness of the composite was also obtained, reaching 275.0 MPa and 5.26 MPa m1/2, respectively. [ABSTRACT FROM AUTHOR]

Focus on advancement of energy storage has now turned to curbing carbon emissions in the transportation sector by adopting electric vehicles (EVs). Technological advancements in lithium‐ion batteries (LIBs), valued for their lightweight and high capacity, are critical to making this switch a reality. Integrating structurally enhanced LIBs directly into vehicular design tackles two EV limitations: vehicle range and weight. In this study, 3D‐carbon (3D‐C) lattices, prepared with an inexpensive stereolithography‐type 3D printer followed by carbonization, are proposed as scaffolds for Li metal anodes for structural LIBs. Mechanical stability tests revealed that the 3D‐C lattice can withstand a maximum stress of 5.15 ± 0.15 MPa, which makes 3D‐C lattices an ideal candidate for structural battery electrodes. Symmetric cell tests show the superior cycling stability of 3D‐C scaffolds compared to conventional bare Cu foil current collectors. When 3D‐C scaffolds are used, a small overpotential (≈0.075 V) is retained over 100 cycles at 1 mA cm−2 for 3 mAh cm−2, while the overpotential of a bare Cu symmetric cell is unstable and increased to 0.74 V at the 96th cycle. The precisely oriented internal pores of the 3D‐C lattice confine lithium metal deposits within the 3D scaffold, effectively preventing short circuits. [ABSTRACT FROM AUTHOR]

A kinetic model of the formation of a pyrocarbon layer on the surface of filaments of a carbonized PAN fiber is proposed. The resulting kinetic model is confirmed by experimental data. The formation of a pyrocarbon layer on an individual carbon fiber filament is described with a prediction of an increase in the thickness of the carbon layer on a bundle of filaments after a long cycle of CVD. [ABSTRACT FROM AUTHOR]

The mechanical properties of anisotropic carbons such as the pyrocarbon (pyC) matrices in C/C composites remain poorly documented, especially at elevated temperatures where these materials find most of their applications. We provide here a comprehensive molecular dynamics investigation of the high temperature – up to 4000 K – elastic behavior of six nanoscale pyC models in the context of fast temperature increases, not allowing for major structural modifications such as graphitization. We show that the structure of the most anisotropic and less disordered carbons, like the rough laminar (RL) pyC, is mostly not affected by annealing at the nanosecond timescale, aside from healing unstable defects like two-coordinated atoms at graphene edges. Conversely, highly disordered and less anisotropic carbons like the smooth laminar (SL) pyC show some significant rearrangements at grain boundaries and the development of some limited microporosity. The elastic constants of all highly anisotropic models moderately decrease with increasing temperature, somehow similarly to what is observed for graphite. Elastic constants of the SL pyC show a stronger decrease at high temperature, due to the decrease in density even though all models retain an important degree of stiffness up to 4000 K.

3D printing has emerged as a highly efficient process for fabricating electrodes in hydrogen evolution through water splitting, whereas metals are the most popular choice of materials in hydrogen evolution reactions (HER) due to their catalytic activity. However, current 3D printing solutions face challenges, including high cost, low surface area, and sub-optimal performance. In this work, we introduce metal-deposited 3D printed pyrolytic carbon (PyC) as a facile and cost-effective HER electrode. We adopt an integrated approach of resin 3D printing, pyrolysis, and electrochemical metal deposition. 3D printing of a resin and its subsequent pyrolysis led to 3D complex architectures of the conductive substrate, facilitating the electrochemical metal deposition and leading to layered 3D metal architecture. Both monolayers of metals (such as copper and nickel) and bi-metallic 3D PyC structures are demonstrated. Each metal layer thickness ranges from 6 to10 µm. The metal coatings, particularly the bi-metallic configurations, result in achieving significantly higher mechanical properties under compressive loading and improved electrical properties due to the synergistic contributions from each metal counterpart. The metalized PyC structures are further demonstrated for HER catalysts, contributing to the development of highly efficient and durable catalyst systems for hydrogen production. Among the materials studied here, Ni@Cu bimetallic 3D PyC electrodes are particularly well-suited, demonstrating a low HER overpotential value of 264 mV (100 mA/cm2, KOH (1 M)) with corresponding Tafel slopes of 107 mV/dec, with exceptional stability during a 10 h operation at a high applied current of −50 mA/cm2.

In this work, chopped carbon fibre reinforced silicon carbide (CCF/SiC) composites were fabricated by selective laser sintering (SLS) combined with reaction melt infiltration (RMI), using the SiC interface and pyrolytic carbon layer as a dual protection to protect the CCF from the erosion of molten silicon. The pyrolytic carbon layer encapsulates the CCF@SiC and the outer carbon preferentially reacts with silicon to form a β-SiC layer, which hinders the reaction of liquid silicon to CCF. Moreover, the fine-crystal β-SiC generated by the Si–C reaction optimizes the microstructure and enhances the mechanical performance of CCF/SiC composites. The CCF under the dual protection maintains its original high strength and high modulus, and the toughness of the CCF/SiC composites is significantly improved through the fibre debonding and fibre pull-out mechanism. The bending strength and toughness of CCF/SiC composites are 265.2 MPa and 3.5 MPa m1/2, respectively. The insights gained from this study contribute to a better understanding of microstructural engineering in SLS&RMI-fabricated CCF/SiC composites. This paves the way for future breakthroughs in composite material design and low-cost manufacturing for extreme environments. [ABSTRACT FROM AUTHOR]

While shoulder hemiarthroplasty is still used to treat young patients with shoulder pathology, the use of this procedure has substantially declined in recent years due to its significant complication profile. Glenoid wear with arthrosis is one of the major postoperative complications following shoulder hemiarthroplasty, and efforts to prevent this complication led many scientists to explore alternative weight-bearing surfaces on arthroplasty implants to decrease joint wear and improve patient outcomes. Pyrolytic carbon, or pyrocarbon, is a material that has better biocompatibility, survivorship, strength, and wear resistance compared to the materials used in traditional shoulder hemiarthroplasty. Pyrocarbon implants have been used in orthopedics for over 50 years; recently, their utility in shoulder hemiarthroplasty has garnered much interest. The purpose behind the use of pyrocarbon in shoulder hemiarthroplasty is to decrease the risk of progressive glenoid wear, especially in young active patients in whom joint preservation is important. Promising survivorship and outcomes have been demonstrated by recent studies, including limited glenoid wear following pyrocarbon hemiarthroplasty. Nevertheless, these clinical studies have been limited to relatively small case series with limited long-term follow-up. Accordingly, additional research and comparative studies need to be conducted in order to properly assess the therapeutic efficacy and value of pyrocarbon hemiarthroplasty. [ABSTRACT FROM AUTHOR]

Maskless UV photolithography is increasingly used, especially in research environments where low turn-around time for new designs improves productivity. Here, we fabricate pyrolytic carbon interdigitated microelectrodes with small interelectrode gaps, good adhesion to the carrier substrate, high surface area and excellent electrochemical properties using maskless UV photolithography with two negative epoxy-based photoresists, namely the commonly used SU-8 and the recently developed mr-DWL. The minimum realizable trench width in 15 μm thick photoresist films is 2.4 ± 0.15 μm for mr-DWL 5 and 3.1 ± 0.10 μm for SU-8 2035. After pyrolysis, the two resulting pyrolytic carbon materials show similar electrochemical properties. However, shrinkage during pyrolysis is significantly lower for mr-DWL compared to SU-8, which is beneficial for the fabrication of interdigitated microelectrodes. Furthermore, delamination of the electrodes during processing and operation is prevented due to the introduction of poly silicon adhesion structures. This work provides valuable insights into maskless UV lithography as well as into the pyrolytic carbon process to increase the yield, performance and productivity for fabrication of microelectrodes.

Hemishoulder arthroplasty (HSA) is a more conservative alternative to total shoulder arthroplasty for young and active patients with minimal glenoid erosion or deformity. Pyrocarbon humeral heads were introduced as an alternative to metallic humeral heads, which were associated with glenoid erosion in 28%-43%. The purpose of this study was to evaluate the progression of glenoid erosion and clinical scores of HSA using pyrocarbon humeral heads from short- (2-4 years) to midterm (5-9 years). We retrieved the records of 45 consecutive patients who underwent HSA with pyrocarbon humeral heads from 2013 to 2017. Patients were evaluated radiographically and clinically at a first follow-up (2-4 years) and a second follow-up (5-9 years). Preoperative glenoid morphology was assessed using computed tomography scans, and glenoid erosion was assessed using plain radiographs according to Sperling et al. The Constant score (CS), American Shoulder and Elbow Surgeons (ASES) score, and Subjective Shoulder Value (SSV) score were assessed by an independent observer. From the initial cohort of 45 patients, 2 underwent revision surgery (4.4%) due to persistent pain (without signs of rotator cuff pathology or glenoid erosion) and 6 were lost to follow-up (13%), leaving 37 for outcome assessment (82%). At the first follow-up of 2.2 ± 0.4 years, all clinical scores improved substantially (CS from 29.3 ± 13.5 to 76.7 ± 14.4, ASES from 23.7 ± 15.6 to 87.0 ± 16.0, and SSV from 25.3 ± 12.2 to 84.1 ± 15.2), and at the second follow-up of 6.2 ± 1.2 years, good clinical scores were maintained (CS from 76.7 ± 14.4 to 80.8 ± 16.0, ASES from 87.0 ± 16.0 to 92.3 ± 15.0, and SSV from 84.1 ± 15.2 to 82.8 ± 18.3). At the second follow-up, glenoid erosion was moderate in 9 (24%) and severe in 3 (8.1%). When comparing with immediate postoperative radiographs, 10 shoulders exhibited progression of glenoid erosion by 1 grade (n = 9) or 2 grades (n = 1). Pyrocarbon humeral heads for HSA grant satisfactory clinical scores with minimal glenoid erosion. [ABSTRACT FROM AUTHOR]

The success of traditional shoulder hemiarthroplasty (HA) with cobalt-chromium heads is limited by painful glenoid erosion with problematic bone loss. Hemiprostheses with pyrolytic carbon (PyC) heads have shown reduced glenoid erosion in experimental laboratory studies. Few in vivo data are available. We performed a single-center consecutive cohort study of 31 of 34 patients (91%) who underwent PyC HA between September 2013 and June 2018. In 11 of these patients, concentric glenoid reaming was additionally performed. The mean follow-up period was 5.5 years (range, 3.5-7 years). Standardized radiographs were taken, and clinical function (Constant score) and pain (visual analog scale score) were recorded. Anteroposterior radiographs were analyzed according to an established method by 2 independent observers: A line parallel to the superior and inferior glenoid rim was translated to the most medial point of the glenoid surface. A further parallel line was placed on the spinoglenoid notch. The distance between these 2 lines was measured. Measurements were scaled using the known diameter of the implanted humeral head component. To assess eccentric erosion, anteroposterior and axial images were classified according to Favard and Walch, respectively. Mean medial glenoid erosion measured 1.4 mm at an average of 5.5 years of follow-up. In the first year, 0.8 mm of erosion was observed, significantly more than the average erosion per year of 0.3 mm (P <.001). Mean erosion per year was 0.4 mm in patients with glenoid reaming vs. 0.2 mm in those without reaming (P =.09). An evolution of glenoid morphology was observed in 6 patients, of whom 4 had a progression of the erosion grade. The prosthesis survival rate was 100%. The Constant score improved from 45.0 preoperatively to 78.0 at 2-3 years postoperatively and 78.8 at latest follow-up (5.5 years postoperatively) (P <.001). The pain score on a visual analog scale decreased from 6.7 (range, 3-9) preoperatively to 2.2 (range, 0-8) at latest follow-up (P <.001). There was a weak correlation (r = 0.37) between erosion and pain improvement (P =.039) and no correlation between erosion and change in Constant score (r = 0.06). PyC HA caused little glenoid erosion and a sustained improvement in clinical function in our cohort at mid-term follow-up. PyC demonstrates a biphasic development of glenoid erosion, with a reduced rate after the first year. PyC HA should therefore be considered as an alternative to cobalt-chromium HA and to anatomical total shoulder arthroplasty for patients with a high risk of glenoid component complications. [ABSTRACT FROM AUTHOR]

The accumulation of waste tires has resulted in very urgent environmental problems. Pyrolysis has been regarded as a green eco-friendly technology to deal with waste tires, and it is vital to make use of the pyrolysis carbon. Herein, we propose a new way to utilize pyrolysis carbon, to prepare carbon nanotubes with the help of ferrocene. The optimal preparation processes were determined by optimizing the parameters including the solvent, temperature, time, etc. The results of scanning electron microscopy and transmission electron microscopy evidenced the successful formation of carbon nanotubes. Meanwhile, the Brunauer–Emmett–Teller (BET) method and N2-adsorption showed that the yielded carbon nanotubes featured a large surface area and abundant pore structure in comparison with the pyrolytic carbon. Finally, the as-prepared carbon nanotubes were applied as the supports for Pt-based catalysts for the dehydrogenation of methylcyclohexane to produce hydrogen. The results showed that the Pt/carbon-nanotubes catalyst exhibited the highest conversion of methylcyclohexane (28.6%), stability, and hydrogen evolution rate (336.9 mmol/gPt/min) compared to the resulting Pt/commercial-activated-carbon (13.6% and 160.2 mmol/gPt/min) and Pt/pyrolytic-carbon catalysts (0.19% and 2.23 mmol/gPt/min). [ABSTRACT FROM AUTHOR]

To reduce the lattice oxygen content of Si3N4 green bodies, samples were prepared using an N,N-dimethylacrylamide (DMAA) system. The endothermic and exothermic peaks are related to the decomposition of organic matter and the reaction between pyrolytic carbon and impurity oxides in the sintering process. Multi-step heat preservation during the thermal degreasing process reduced the carbon content and defects. The α→β phase transformation and aspect ratio of grains changed from 89.2% to 4.84:1 at 1640 °C to 96.3% and 7.80:1 at 1700 °C, respectively. The relative density, hardness, fracture toughness, and thermal conductivity of the Si3N4 samples reached 98.5%, 1353 HV, 8.51 MPa·m1/2, and 97.1 W·m−1·K−1, respectively. Pyrolytic carbon can react with SiO2, which reduces the content of the glass phase in the green body and affects the dissolution and precipitation process and lattice oxygen content. In the structure of the Si3N4 sample, carbon particles with sizes of 100–500 nm and near-spherical shapes were observed. Intergranular-phase YMgSi2O5N was formed during the sintering process, which was conducive to improving the thermal conductivity. This article uses lower temperature and no pressure conditions to prepare Si3N4 ceramics, which can provide reference for batch and low-cost production.

The main purpose of these studies was to obtain carbon–carbon composites with a core built of carbon fibers and a matrix in the form of pyrolytic carbon (PyC), obtained by using the chemical vapor deposition (CVD) method with direct electrical heating of a bundle of carbon fibers as a potential electrode material for nerve tissue stimulation. The methods used for the synthesis of PyC proposed in this paper allow us, with the appropriate selection of parameters, to obtain reproducible composites in the form of rods with diameters of about 300 µm in 120 s (CF_PyC_120). To evaluate the materials, various methods such as scanning electron microscopy (SEM), scanning transmission electron microscope (STEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and tensiometer techniques were used to study their microstructural, structural, chemical composition, surface morphology, and surface wettability. Assessing their applicability for contact with nervous tissue cells, the evaluation of cytotoxicity and biocompatibility using the SH-SY5Y human neuroblastoma cell line was performed. Viability and cytotoxicity tests (WST-1 and LDH release) along with cell morphology examination demonstrated that the CF_PyC_120 composites showed high biocompatibility compared to the reference sample (Pt wire), and the best adhesion of cells to the surface among all tested materials. [ABSTRACT FROM AUTHOR]

While shoulder hemiarthroplasty is still used to treat young patients with shoulder pathology, the use of this procedure has substantially declined in recent years due to its significant complication profile. Glenoid wear with arthrosis is one of the major postoperative complications following shoulder hemiarthroplasty, and efforts to prevent this complication led many scientists to explore alternative weight-bearing surfaces on arthroplasty implants to decrease joint wear and improve patient outcomes. Pyrolytic carbon, or pyrocarbon, is a material that has better biocompatibility, survivorship, strength, and wear resistance compared to the materials used in traditional shoulder hemiarthroplasty. Pyrocarbon implants have been used in orthopedics for over 50 years; recently, their utility in shoulder hemiarthroplasty has garnered much interest. The purpose behind the use of pyrocarbon in shoulder hemiarthroplasty is to decrease the risk of progressive glenoid wear, especially in young active patients in whom joint preservation is important. Promising survivorship and outcomes have been demonstrated by recent studies, including limited glenoid wear following pyrocarbon hemiarthroplasty. Nevertheless, these clinical studies have been limited to relatively small case series with limited long-term follow-up. Accordingly, additional research and comparative studies need to be conducted in order to properly assess the therapeutic efficacy and value of pyrocarbon hemiarthroplasty.

Hydrogen production via methane pyrolysis is projected to have a key role in achieving net zero GHG emission by 2050. Carbon makes up to 75% by mass of the products of methane pyrolysis, indicating the importance of a thorough characterization to find its potential applications. A new approach is methane pyrolysis utilizing microwaves, where the carbon product serves as receptors for the microwave energy. In this method, methane decomposes and forms solid carbon. In this study, we evaluated the morphological and structural features of the produced carbon using SEM, XRD, XPS, Raman spectroscopy, and thermogravimetric analysis. The analysis indicates that the pyrolytic carbon produced through this process is highly pure and exhibits a semi-graphitic structure with localized defects. Additionally, the surface morphology of the carbon material was observed to possess a rough cauliflower-like texture. A thorough characterization of carbon revealed several potential applications, including the utilization of granular carbon in electric arc furnace for steelmaking, the feedstock for graphene production, and serving as an anode material in Na-ion batteries with further optimization of the production process. Safe sequestration of the carbon due to limited demand is feasible as the carbon is pure and oxygen-free, indicating its potential to remain unreacted over a long period after sequestration.

Hemiarthroplasty is often considered in the setting of preserved glenoid cartilage given the high risk of revision associated with total shoulder arthroplasty. Pyrocarbon (PyC) has been used as an implant material that theoretically allows for formation of a neo-membrane that would act like cartilage to reduce glenoid wear. The purpose of this study was to evaluate the clinical outcomes, radiographic outcomes, revision rates, and complication rates in the existing literature on shoulder hemiarthroplasty using PyC. The MEDLINE, Embase, and Scopus databases were searched for articles relating to shoulder hemiarthroplasty using the terms "pyrocarbon" or "pyrolytic carbon." Abstracts and articles were screened against predefined inclusion and exclusion criteria, with a minimum of 24 months' follow-up required. Data on patient demographic characteristics, clinical outcome scores, complications, revision rates, and radiographic findings were recorded. Where appropriate, meta-analysis was performed. Twelve studies were selected for final inclusion, with a total of 536 patients. Among the studies reporting preoperative and postoperative range of motion (ROM), an overall improvement in ROM was observed. The mean Constant score was 70.9 points postoperatively, with a mean improvement of 36.2 points (n = 359, 9 studies). Radiographically, 22.8% of patients (n = 536, 8 studies) had evidence of glenoid erosion, 10.4% had changes in implant positioning, and 9.9% had tuberosity thinning. In addition, 1.5% of patients had radiographic subacromial space reduction, whereas 0.7% had an increase in tuberosity thickness. Across all studies, there was an 8.6% complication rate, with the most common cause being glenoid erosion (2.6%, n = 14). There was an overall 7.7% revision rate (n = 41), with 63% of revisions (n = 26) undergoing conversion to reverse or total shoulder arthroplasty. PyC hemiarthroplasty shows overall improvements in ROM and patient-reported outcomes for patients. However, there remains concern for glenoid erosion on radiographic evaluation at minimum 2-year follow-up. Although preliminary studies have shown encouraging results, this systematic review emphasizes the need for longer-term follow-up studies with further radiographic evaluation of the severity of glenoid erosion and the association with functional outcomes and failure risk. [ABSTRACT FROM AUTHOR]

This review focuses on techniques for modifying the surface of carbon that is produced from sustainable resources, such as pyrolytic carbon. Many of these materials display high specific surface area and fine particle distribution. Functionalization of a surface is a commonly used approach in designing desired surface properties of the treated material while retaining its bulk properties. Usually, oxidation is a primary step in carbon functionalization. It can be performed as wet oxidation, which is a type of chemical surface modification. Wet oxidation is usually performed using nitric acid and hydrogen peroxide, as well as using hydrothermal and solvothermal oxidation. On the other side, dry oxidation is representative of physical surface modification. This method is based on corona discharge and plasma oxidation which are promising methods that are in line with green chemistry approaches. Whilst the oxidation of the carbon surface is a well-known method, other chemical modification techniques, including cycloadditions and various radical reactions on graphene layers, are presented as an alternative approach. Regarding secondary functionalization, coupling organosilanes to activated carbon is a common technique. Organosilanes bearing reactive groups present a bridge between inorganic species and polymer systems, e.g., epoxy and polyurethane resins, and facilitate the use of carbonaceous materials as reinforcing components for polymers and thermosetting resins. Along with the presented functionalization methods, this review also provides an overview of new applications of modified (i.e., functionalized) carbon materials, e.g., for the building industry, wastewater treatment, semiconducting materials and many more. [ABSTRACT FROM AUTHOR]

Carbon/carbon-polyimide composites were prepared by chemical vapor infiltration and vacuum-pressure impregnation curing process. Firstly, the carbon felt was deposited with pyrolytic carbon by chemical vapor infiltration method to prepare porous carbon/carbon materials with pyrolytic carbon contents of 7.33%(mass fraction, the same below), 14.55% and 22.00%, respectively. Then, through a specific impregnation curing process, the carbon/carbon-polyimide composites P1, P2 and P3 and the control group P0 without pyrolytic carbon were obtained in turn. Through SEM, linear expansion coefficient test and mechanical properties test, the effects of different pyrolytic carbon contents on the microstructure, average linear expansion coefficient and mechanical properties of carbon/carbon-polyimide composites were investigated. The results show that in the temperature range of 20-300℃, the XY-direction average linear expansion coefficients of P0, P1, P2 and P3 are between (0.67-0.79)×10-6℃-1, and the XY-direction average linear expansion coefficients of four groups are basically the same. The Z-direction average linear expansion coefficients of P1, P2 and P3 decrease by 41.6%, 41.8% and 24.1%, respectively compared with P0. Pyrolytic carbon significantly reduces the Z-direction average linear expansion coefficient of materials. The XY-direction compressive strengths of P0, P1, P2 and P3 are 243.91, 244.73, 216.65 MPa and 210.79 MPa, respectively, and the Z-direction compressive strengths are 269.22, 258.80, 246.68 MPa and 219.20 MPa, respectively. The compressive strength of P1 is equivalent to that of P0. The Z-direction bending strengths of P0, P1, P2 and P3 are 92.77, 77.11, 80.71 MPa and 86.06 MPa, respectively. Different pyrolytic carbon contents have different effects on the mechanical properties of materials. The lower pyrolytic carbon content can basically maintain compressive strength of materials, while the higher pyrolytic carbon content can basically maintain bending strength of materials.

Background: In vitro data demonstrate the potential benefits of the pyrocarbon as a bearing material against cartilage or bone. And pyrocarbon-free interposition arthroplasty has been used with positive outcomes for over 10 years for hand and wrist joint replacements. This study reports the midterm results of a Pyrocarbon Interposition Shoulder Arthroplasty (PISA) in primary and secondary glenohumeral osteoarthritis and in avascular osteonecrosis. Methods: This prospective noncontrolled, multicenter study included 67 consecutive patients who underwent PISA in France and Sweden. Results: A cohort of 48 patients, aged 50 ± 12 years, was available for clinical assessment at a mean follow-up of 67.6 ± 9.3 months. A favorable change was reported with a mean absolute Constant score improvement of 32 ± 20 points. The highest Constant score improvement was observed in patients with avascular osteonecrosis (42 ± 18 points; P ≤ .0001). Between the earliest and the latest follow-up, radiographic analyses revealed only 2 major glenoid erosions and 4 tuberosity thinnings and thus that 86.4% of 44 shoulders remained stable with no or minor radiologic evolutions. The survival rate was 84 % at 65 months of follow-up considering all causes of revision. Conclusion: The radiographic findings seem to confirm the interest of pyrocarbon in preserving bony surfaces. But the risk of tuberosity thinning suggests considering the use of PISA with caution in most degenerative glenohumeral joint pathologies, although the midterm outcomes highlight PISA as a suitable solution for patients presenting with posttraumatic osteonecrosis without malunion of the tuberosities and with an intact rotator cuff.

Polymer-derived pyrolytic carbons (PyCs) are often desirable for low density high-temperature structural applications when they can be reinforced with high stiffness and strength fibers to address brittleness. Nanofibers, such as aligned carbon nanotubes (A-CNTs), can be an ideal reinforcement owing to their high mass-specific properties, and while modeling suggests that properties of A-CNTs at high volume fractions (i.e., 10–30 vol%) could yield significant enhancements, it is unknown how CNT confinement influences processing, as such materials have never been synthesized. Here, we report process development demonstrating the first successful fabrication of fully infused, void-free A-CNT carbon matrix nanocomposites (A/C-NCs) via polymer infiltration pyrolysis (PIP) that establishes a platform to study nanofiber-reinforced polymer-derived ceramics. The size of the average A/C-NC graphitic crystallites increases as CNT vol% increases up to 30 vol%, and the inter-layer separation of the PyC graphitic crystallites decreases, evidencing a nanoscale confinement effect observed in concert with increased mechanical performance. Vickers microhardness testing in the axial CNT direction of A/C-NCs shows agreement with prior data for low vol% CNTs in PyC and mechanical modeling, where specific hardness increases from ∼ 3.3 GPa/(g/cm3) for PyC to ∼ 6.7 GPa/(g/cm3) for 30 vol% A/C-NCs, demonstrating A/C-NCs as an advantaged superhard lightweight material. [Display omitted] • Fabrication of pyrolytic carbon composites with 1-30 vol% aligned carbon nanotubes. • Vacuum- and capillary-assisted infiltration of phenolic resin enable full infusion. • Four polymer infiltration pyrolysis cycles decrease porosity and increases density. • Graphitic crystallites in matrix are longer and denser with nanotube reinforcement. • Specific microhardness increases up to 30 vol% carbon nanotubes, rivaling diamond. [ABSTRACT FROM AUTHOR]

The accumulation of waste tires has resulted in very urgent environmental problems. Pyrolysis has been regarded as a green eco-friendly technology to deal with waste tires, and it is vital to make use of the pyrolysis carbon. Herein, we propose a new way to utilize pyrolysis carbon, to prepare carbon nanotubes with the help of ferrocene. The optimal preparation processes were determined by optimizing the parameters including the solvent, temperature, time, etc. The results of scanning electron microscopy and transmission electron microscopy evidenced the successful formation of carbon nanotubes. Meanwhile, the Brunauer–Emmett–Teller (BET) method and N2-adsorption showed that the yielded carbon nanotubes featured a large surface area and abundant pore structure in comparison with the pyrolytic carbon. Finally, the as-prepared carbon nanotubes were applied as the supports for Pt-based catalysts for the dehydrogenation of methylcyclohexane to produce hydrogen. The results showed that the Pt/carbon-nanotubes catalyst exhibited the highest conversion of methylcyclohexane (28.6%), stability, and hydrogen evolution rate (336.9 mmol/gPt/min) compared to the resulting Pt/commercial-activated-carbon (13.6% and 160.2 mmol/gPt/min) and Pt/pyrolytic-carbon catalysts (0.19% and 2.23 mmol/gPt/min).

In high temperature gas-cooled reactors (HTGRs), Tri-isotropic (TRISO)-coated fuel particles are employed as fuel. In the high burnup coated fuel particle, stress due to fission gas pressure and irradiation-induced pyrolytic carbon (PyC) shrinkage is introduced into the coating layers and consequently the stress could cause failure of coating layers under high burnup irradiation condition. A failure model has developed to predict failure fraction of TRISO-coated particle under high burnup irradiation. In the model, failure probability is strongly dependent on the irradiation characteristics of PyC. This paper describes the outline of the failure model and evaluation result of high burnup fuel irradiation experiment by the model.

Pyrocarbon disc interposition arthroplasty is an effective treatment for thumb base osteoarthritis. However, as with all implant techniques, the disc can (sub)luxate over time. The relationship between disc position, the experienced pain, and the necessity for revision surgery is not known. This study evaluated the effect of radiographic pyrocarbon disc position on the Michigan Hand Questionnaire (MHQ) outcome measurement. In addition, the correlation between disc position and other factors, including pain intensity, thumb strength, and occupation, was assessed. In this retrospective study, we included 136 patients (161 thumbs) with a mean follow-up of 6.7 years (range 3.3–11). Radiographs were scored on disc position and classified as 'well aligned' (Grade 1) up to 'luxated' (Grade 4). A database used for outcome measures included MHQ scores, pain intensity, satisfaction, thumb strength, range of motion, occupation, and hand dominance. In bivariate analyses, we assessed any association between disc position and outcome measurements. Eighty of the 136 implants (59%) were well-positioned (not displaced), 41% were (slightly) displaced (grade 2–3). No relationship existed between the degree of disc displacement and MHQ scores. Manual labor occupation was the only factor that correlated with more severe disc displacement. We could not detect any association between disc position and other outcome variables including pain intensity, thumb strength, or hand dominance. In conclusion, our study suggests that radiographic disc displacement has little clinical consequences. Future studies must assess if there is a causality between heavy mechanical stress to the CMC1 joint and luxation of the pyrocarbon disc over time. Level of evidence: IV Therapeutic—Retrospective case series. [ABSTRACT FROM AUTHOR]

Baicalin obtained from natural plants has essential medical value, so the development of accurate and sensitive quantitative methods for it is one of the most important tasks. Here, the FeO X /Fe@porous carbon composite (Fe@C) was synthesized by solvothermal method and carbonized at different temperatures under an N 2 atmosphere, and an electrochemical sensor designed based on this material was applied to the accurate and rapid determination of baicalin. According to the results of physical and electrochemical characterization, Fe@C at different pyrolysis temperatures exhibited different morphologies and different electrochemical properties, while the Fe@C pyrolyzed at 800 °C had the optimum performance. Compared with NH 2 -MIL-88B, the pyrolysis greatly reduces the charge transfer internal resistance of the material and has a larger porosity and specific surface area, resulting in an eminent electrochemical signal for the detection of baicalin. The sensor Fe@C-800/GCE not only has a linear range of 4 nM–700 nM with a low limit of detection of 1.16 nM for the detection of baicalin, but also has outstanding repeatability, anti-interference and stability for the detection of baicalin in several natural plant samples and herbal medicines samples. This work presents several pyrolytic NH 2 -MIL-88B as electrochemical sensors for the detection of baicalin for the first time, providing a novel idea for the application of MOFs derivatives in environmental analysis. [Display omitted] • Pyrolyzed NH 2 -MIL-88B has large specific surface area and high catalytic activity. • The optimal pyrolysis temperature and catalytic properties of Fe@C has been found. • The baicalin sensor based on Fe@C has been constructed for the first time. • The sensor has high sensitivity and wide linear range for detection of baicalin. • The sensor has shown excellent performance in analysis of actual samples. [ABSTRACT FROM AUTHOR]

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As to the issue that the quality and market application of waste tires derived pyrolytic carbon derived from waste tires directly affect the economy of the pyrolysis process, the pyrolysis techndogy, main influencing factors and recycle utilization of pyrolytic carbon were reviewed. It was found that the pyrolysis of waste was a complex process, which was mainly affected by pyrolysis temperature, heating rate, operating pressure and rection time. The rate of carbon content of pyrolytic carbon of more than 80%. It has been widely used in the preparation of active carbon, the rubber reinforcing agent, the asphalt modifier, the battery and ink materials, etc. In the future, the pyrolysis system of waste tires should be further optimized, and the pyrolysis mechanism and kinetics process should be further studied to realize the precise control of the pyrolysis. Meanwhile, the integrated technology integratingwaste tires pretreatment, pyrolysis and pyrolytic carbon deep processing should be developed to further improve the quality of pyrolytic carbon and broaden its applications, finally realizing the efficient utilization of pyrolytic carbon. [ABSTRACT FROM AUTHOR]

\nIMPACT STATEMENT3D printing has emerged as a highly efficient process for fabricating electrodes in hydrogen evolution through water splitting, whereas metals are the most popular choice of materials in hydrogen evolution reactions (HER) due to their catalytic activity. However Current 3D printing solutions face challenges, including high cost, low surface area, and sub-optimal performance. In this work, we introduce metal-deposited 3D printed pyrolytic carbon (PyC) as a facile and cost-effective HER electrode. We adopt an integrated approach of resin 3D printing, pyrolysis, and electrochemical metal deposition. 3D printing of a resin and its subsequent pyrolysis led to 3D complex architectures of the conductive substrate, facilitating the electrochemical metal deposition and leading to layered 3D metal architecture. Both monolayers of metals (such as copper and nickel), and bi-metallic 3D PyC structures are demonstrated. Each metal layer thickness ranges from 6 to10 µm. The metal coatings, particularly the bi-metallic configurations, result in achieving significantly higher mechanical properties under compressive loading and improved electrical properties due to the synergistic contributions from each metal counterpart. The metalized PyC structures are further demonstrated for HER catalysts, contributing to developing highly efficient and durable catalyst systems for hydrogen production. Among the materials studied here, Ni@Cu bimetallic 3D PyC electrodes are particularly well-suited, demonstrating low HER overpotential value 264 mV (100 mA/cm2, KOH (1 M)) with corresponding Tafel slopes of 107 mV/dec, with exceptional stability during a 10 h operation at a high applied current of -50 mA/cm2.This study introduces electrodeposited bilayer copper-nickel coated 3D printed pyrolytic carbon structures as cost-effective electrodes and demonstrates their performance as effective electrocatalysts in hydrogen evolution reaction applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A macroscopic amount of boron-enriched pyrolytic carbon is fabricated by the high-temperature low-pressure CVD process. • A two-phase crystalline system consisting of intertwined graphene layers nterspersed with boron carbide provids high microhardness of the material. • Tree-like dendritic structures are formed by adding into reactor a small amount of oxygen-containing compounds. • Vertical orientation of the graphite substrate planes allows comparative studying the material depending on the boron content. In this paper we report the synthesis and characterization of the boron-enriched pyrolytic carbon (B-PyC). In the research we aimed to propose a material demonstrating high strength characteristics and heat resistance, durability, chemical inertness and biocompatibility. The material has been synthesized by high temperature low pressure CVD method. The synthesis is carried out on the inner surface of a vertically oriented hollow graphite hexagonal prism heated to the temperatures 1450–1570 °C. Controlled low-density flows of nitrogen, boron trichloride and carbonaceous gas react in this zone producing B-PyC film deposited on the vertical graphite plates. Morphology, mechanical and physical properties of this material was investigated using X-ray diffraction, scanning and transmission electron microscopy, mechanical testing instrumentations, thermogravimetric and thermal analysis. It was found that during the synthesis a two-phase crystalline system is organized comprising fragments of graphene layers (pyrolytic carbon) and boron carbide B 4 C. Such a structure provides high mechanical properties of the material and their stability in a wide temperature range, heat resistance, chemical inertia and biocompatibility. Depending on the synthesis conditions, the micro hardness may vary in a wide range including the range 100–140 HV the most attractive for traumatology and cardiac surgery as well as for a variety of engineering applications. [ABSTRACT FROM AUTHOR]

Carbon's electrochemistry depends on its type and microstructure, and how these affect the electrode's electronic density of states. We demonstrate how pyrolysis of electro-mechanically stressed Polyacrylonitrile (PAN) nanofibers, infused with carbon nanotubes, will result in a unique graphitic electrode, which possesses enhanced and multifaceted electrochemical behavior. As corroborated by materials characterization, the microstructure of the stress-activated pyrolytic carbon (SAPC) characteristically contains a high proportion of disorders in the forms of edge planes and embedded heterogeneous nitrogen atoms. These disorders introduce a range of energy states near the Fermi level, yielding enhanced kinetics in the as-synthesized SAPC electrodes. A comprehensive electrochemical study of the SAPC electrode in surface sensitive ([Fe(CN)6]3-/4-), surface insensitive ([IrCl6]2-/3-), and adsorption sensitive (dopamine) redox probes demonstrates 5–14-fold increases in its heterogeneous electron transfer rate compared to regular PAN-based carbon electrodes. The fast kinetics of SAPC electrodes in adsorption sensitive analytes translates into its capability for simultaneous detection of dopamine, uric acid, and ascorbic acid. The results point to a new class of pyrolytic carbon electrodes with an attractive electrocatalytic capacity, geared toward electrochemical sensing platforms.

Carbon's electrochemistry depends on its type and microstructure, and how these affect the electrode's electronic density of states. We demonstrate how pyrolysis of electro-mechanically stressed Polyacrylonitrile (PAN) nanofibers, infused with carbon nanotubes, will result in a unique graphitic electrode, which possesses enhanced and multifaceted electrochemical behavior. As corroborated by materials characterization, the microstructure of the stress-activated pyrolytic carbon (SAPC) characteristically contains a high proportion of disorders in the forms of edge planes and embedded heterogeneous nitrogen atoms. These disorders introduce a range of energy states near the Fermi level, yielding enhanced kinetics in the as-synthesized SAPC electrodes. A comprehensive electrochemical study of the SAPC electrode in surface sensitive ([Fe(CN)6]3-/4-), surface insensitive ([IrCl6]2-/3-), and adsorption sensitive (dopamine) redox probes demonstrates 5–14-fold increases in its heterogeneous electron transfer rate compared to regular PAN-based carbon electrodes. The fast kinetics of SAPC electrodes in adsorption sensitive analytes translates into its capability for simultaneous detection of dopamine, uric acid, and ascorbic acid. The results point to a new class of pyrolytic carbon electrodes with an attractive electrocatalytic capacity, geared toward electrochemical sensing platforms.

The possibility of using structural carbon materials in molten salt reactors was considered. The influence of the conditions of the main stages of carbon material fabrication processes on the structural and operational characteristics of the resulting materials was analyzed. Directions for the modification of structural graphites were proposed in order to increase their resistance to the internal media of molten salt reactor facilities. [ABSTRACT FROM AUTHOR]

We present a combined experimental and computational study of the elastic behavior of a series of highly anisotropic pyrocarbons, with crystallite sizes L a in the 2–10 nm range, under a -axis compressive load. The materials include a rough laminar and a regenerative laminar pyrocarbon, as-prepared by chemical vapor deposition and after various heat treatments up to 2600 °C, for which a -axis nanoindentation experiments have been performed, showing a significant decrease in the indentation modulus and hardness with increasing L a (or heat treatment temperature). To rationalize this behavior, molecular dynamics simulations of the uniaxial compression of accurate atomistic models of the materials as well as pristine graphite were performed, unraveling significant out-of-plane deformations in the models with increasing compressive strain, leading to elastic softening. More precisely, significant kinks were observed around extended screw dislocation-like defects in the most disordered pyrocarbon at rather large strain levels (∼ 3%). Conversely, graphite rather shows the formation of extended buckles, starting at very low strain values. Finite element modelling shows that such kinking/buckling transitions should take place in a large area under the indenter tip within usual nanoindentation conditions. Both finite element calculation and analytical approximation of the indentation modulus predict the correct trend of decreasing modulus with increasing L a when applied with the elastic tensors computed after the buckling/kinking transitions, certainly proving the importance of the latter in the observed experimental indentation moduli. [ABSTRACT FROM AUTHOR]

The processing of discarded auto tire casings is considered. A thermal process for the treatment of solid organic wastes is developed. A system with little environmental impact is proposed for low-temperature pyrolysis of the auto tires. The products obtained are carbon black (pyrolytic carbon), oils, liquid fuels (gasoline, diesel fuel, and fuel oil), metal cord, and heating oil. The yield and composition of the main pyrolytic products are determined. The production of fuel granules by pressing carbon black and other plant wastes, as well as a combustion accelerator (ammonium nitrate), is assessed. In addition, adsorbent production by creating tablets from carbon black and heat-treated shungite is considered. The sorptional capacity of such tablets is determined. Formulas for the cleavage strength and density of the pressed material are obtained on the basis of static experiment design. Nomograms are obtained for determining the structure and deformational characteristics of the fuel granules and adsorbent, with variation in the pressing parameters. A production line for fuel granules is developed on the basis of the compaction of carbon black and other plant wastes, so as to obtain the product in plate or briquet form. [ABSTRACT FROM AUTHOR]

The main purpose of these studies was to obtain carbon–carbon composites with a core built of carbon fibers and a matrix in the form of pyrolytic carbon (PyC), obtained by using the chemical vapor deposition (CVD) method with direct electrical heating of a bundle of carbon fibers as a potential electrode material for nerve tissue stimulation. The methods used for the synthesis of PyC proposed in this paper allow us, with the appropriate selection of parameters, to obtain reproducible composites in the form of rods with diameters of about 300 µm in 120 s (CF_PyC_120). To evaluate the materials, various methods such as scanning electron microscopy (SEM), scanning transmission electron microscope (STEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and tensiometer techniques were used to study their microstructural, structural, chemical composition, surface morphology, and surface wettability. Assessing their applicability for contact with nervous tissue cells, the evaluation of cytotoxicity and biocompatibility using the SH-SY5Y human neuroblastoma cell line was performed. Viability and cytotoxicity tests (WST-1 and LDH release) along with cell morphology examination demonstrated that the CF_PyC_120 composites showed high biocompatibility compared to the reference sample (Pt wire), and the best adhesion of cells to the surface among all tested materials.

A binary C/C brake disc (i.e., the test brake disc) was prepared with a C/C (pyrolytic carbon/resin carbon) matrix using modified natural gas as the carbon source through the isothermal chemical vapor infiltration (ICVI) process with a directed flow and the pressure impregnation carbonization (PIC) process with liquid-phase furfural acetone resin. The microstructural, mechanical, thermal, friction and wear properties of the test brake disc were comprehensively analyzed and compared with commercial ones. The results showed that the production efficiency of the test brake disc was 36% higher than that of the commercial ones, which were manufactured through a thermal-gradient chemical vapor infiltration (TCVI) process. The favorable mechanical and thermal properties of the test brake disc were comparable to the commercial ones. While the test brake disc had a more consistently rough laminar microstructure on the worn surface of the brake disc than the commercial ones, this avoided the annular grinding grooves on the worn surface after the braking tests. In addition, the test brake disc had a stable friction coefficient with a low dispersion coefficient of 3.90%, which would improve the friction stability of C/C brake discs used in aircrafts. [ABSTRACT FROM AUTHOR]

The solid-state persistent free radicals (PFRs) on pyrolytic carbons are attracting increasing attentions as they can directly degrade pollutants in water, while the redox behaviors and pathways over the PFRs during remediating coexisting aqueous pollutants have never been clarified. Herein, we discovered that the PFRs-induced remediation was an integrated process, where the original PFRs on the model pyrolytic carbon (TLRB) would first deliver electrons to the exterior heavy metals (HMs) forming derivative solid radicals (DSRs). The DSRs then acted as an electroactive bridge to further attract, stabilize, and degrade the surface-bound organic pollutants (OCs), eventually achieving a highly efficient removal of coexisting HMs and OCs. It is appealing to find that the HMs can trigger the in-situ upgrading of original PFRs to the DSRs by acting as an oxidant, rather than a pollutant. Such a peroxide-free regime alleviated the direct self-corrosion by radicals, thus promising a better effectiveness and recyclability of catalytic system. [Display omitted] • • Persistent free radicals (PFRs) coordinating with exterior heavy metals can form strong redox-active sites (DSRs). • The DSRs can directly degrade antibiotics into smaller molecular products without additional oxidant input. • The DSRs facilitated system durability through peroxide-free oxidation. [ABSTRACT FROM AUTHOR]

Surface modification is believed to be one of the most effective solutions to prevent thrombus formation associated with mechanical heart valves. Herein, we report, for the first time, the fabrication of a gradient cobblestone pattern on the pyrolytic carbon (PyC) surface aiming to improve its anti-thrombotic properties. A unique cobblestone pattern with gradient changing interspacing was generated on the PyC surface through laser etching. After coating with fluorosilane, the surface exhibited a water contact angle gradient ranging from 110 to 173°. The morphological and physicochemical properties, mechanical durability, drag reduction, in vitro anti-thrombotic properties, and in vivo biocompatibility of the surface were investigated to evaluate its potential as a heart valve replacement. It was found that the hydrophobic gradient wettability surface exhibited an excellent self-driving effect and mechanical durability, significantly reduced hemolysis rate and platelet adhesion, and prolonged coagulation time compared to the counterpart without gradient wettability. Furthermore, the gradient wettability surface demonstrated excellent in vivo biocompatibility. These findings are important for the design of artificial heart valves with improved anti-thrombotic performance. [Display omitted] [ABSTRACT FROM AUTHOR]

We report a novel hybrid method for fabricating high aspect ratio 3D pyrolytic carbon electrodes combining UV photolithography and additive manufacturing with commercially available SLA 3D printers and materials. By using a 3D printed chip holder, aligned 3D printing on a patterned silicon chip was possible. This allowed for the fabrication of cylindrical polymer micropillars with a height of 2173 ± 26 μm and a width of 316 ± 11 μm on SU-8 precursor structures defining the leads, contact pads and underlying 2D electrode prepared using UV lithography. Microfabrication of 3D structures with these dimensions is impossible to achieve with SU-8 photolithography alone. The hybrid polymer structures were converted into 3D carbon electrodes with high structural integrity using a 3-step pyrolysis process optimized for the specific 3D print resin. During this process, the micropillars shrunk to 30 ± 3% in height and 35 ± 1% in width of the polymer precursor structures, while maintaining the macroscopic shape and microscopic surface roughness. Electrochemical experiments confirmed that the pyrolytic carbon formed a monolithic conductive 3D electrode. The surface roughness contributed to a 17 ± 5% increase in electroactive surface area compared to the geometrical surface area of the micropillars.

The study investigated the morphology, microstructure, structure, texture, and mechanical properties of heat-treated at 1600 °C and 2000 °C pyrolytic carbon (PyC) deposited from methane using various methods such as scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Raman spectroscopy, and ultrasonic dynamic measurements of Young's modulus. The PyC was synthesised at 1100 °C using a chemical vapour deposition (CVD) method with direct electrical heating of the two types of carbon fibres (CFs). The results showed that the PyC had a low- and medium-texture (LT and MT PyC). Analysis of the graphitization trajectory allowed the determination of structural changes in the material as a function of temperature, including the growth of crystallites and an increase in the crystallinity proportion without the significant rearrangement within PyC. The crystallite size and the number of interstitial defects has increased with temperature that controlled mechanical properties. Therefore, based on the results obtained, the most suitable composites for further research in the context of electrodes for stimulation of nervous tissue were obtained at the temperature of their synthesis, i.e. at 1100 °C. [Display omitted] • The matrix area distinguished low-textural (LT) and medium-textural (MT) PyC. • The surface can be significant during the deposition only of initial PyC layers. • Amorphous forms may evolve towards turbostratic ones. • Thermodynamically, the organising process may occur but is kinetically limited. • The mechanism of the graphitization trajectory was the formed domains growth. [ABSTRACT FROM AUTHOR]

This review focuses on techniques for modifying the surface of carbon that is produced from sustainable resources, such as pyrolytic carbon. Many of these materials display high specific surface area and fine particle distribution. Functionalization of a surface is a commonly used approach in designing desired surface properties of the treated material while retaining its bulk properties. Usually, oxidation is a primary step in carbon functionalization. It can be performed as wet oxidation, which is a type of chemical surface modification. Wet oxidation is usually performed using nitric acid and hydrogen peroxide, as well as using hydrothermal and solvothermal oxidation. On the other side, dry oxidation is representative of physical surface modification. This method is based on corona discharge and plasma oxidation which are promising methods that are in line with green chemistry approaches. Whilst the oxidation of the carbon surface is a well-known method, other chemical modification techniques, including cycloadditions and various radical reactions on graphene layers, are presented as an alternative approach. Regarding secondary functionalization, coupling organosilanes to activated carbon is a common technique. Organosilanes bearing reactive groups present a bridge between inorganic species and polymer systems, e.g., epoxy and polyurethane resins, and facilitate the use of carbonaceous materials as reinforcing components for polymers and thermosetting resins. Along with the presented functionalization methods, this review also provides an overview of new applications of modified (i.e., functionalized) carbon materials, e.g., for the building industry, wastewater treatment, semiconducting materials and many more.

[Display omitted] • Pyrolytic carbon from waste tire pyrolysis was used to boost the AD performance. • Pyrolysis temperature for pyrolytic carbon used in AD should be higher than 800 °C. • The conductivity of pyrolytic carbon at 1000 °C is (12.5–25.2) × 104 S/m. • The hydrolysis of vinegar residue is enhanced and the VFA content is 3330 mg/L. • The maximal CH 4 yield is 454.53 mL CH 4 /gVS, representing an increase of 104.4%. Random disposal of waste tires and vinegar residues is deleterious to the environment; these materials can be sufficiently treated using pyrolysis and anaerobic digestion, respectively. In this study, pyrolytic carbon was used to enhance the performance of the anaerobic digestion of vinegar residues, which is a much more economic method comparing with dosing commercial-level carbon based materials. The conductivity of pyrolytic carbon at 1000 °C is much higher than that of commercial activated carbon. At a dosage of 10 g per 29 g of vinegar residues, the maximum volatile fatty acid production was 4225.4 mg COD/L in the reactor (effective volume of 400 mL) with inoculum to substrate ratio (ISR) of 1:1, representing an increase of 50.3% from that of the control reactor. A sufficient dosage is necessary to improve methane yield. The maximum methane yield was obtained at a pyrolytic carbon dosage, obtained at 1000 °C, of 12 g per 29 g of vinegar residues. The results indicated that the differences in the microbial communities of the control and experimental reactors correlated with the performance; however, the deep microbial mechanism of pyrolytic carbon boosting anaerobic digestion performance must be explored in further studies. [ABSTRACT FROM AUTHOR]

The rational design and construction of transition metal catalysts with high performance and low cost are imperative for liquid hydrogen storage materials. In this study, carbon-stabilised ultrathin Co-doped Co x O y nanofilms (C–Co/Co x O y NFs) are prepared by an ionic liquid/water interface strategy for sodium borohydride (NaBH 4) hydrolysis. Owing to its two-dimensional (2D) NFs structure and the protective effect of the composite carbon, C–Co/Co x O y NFs catalyst exhibits remarkable activity and durability in hydrogen generation from NaBH 4 hydrolysis. The hydrogen generation rate achieves 8055 mL·min−1·g Co −1 and the catalyst can be recycled more than 20 times, surpassing most of the reported metal-based catalysts under comparable conditions. This excellent 2D Co-based NFs structure with numerous active sites assists in the activation of NaBH 4 and water molecules to promote hydrogen production. These results provide an in-depth understanding of hydrogen generation from NaBH 4 hydrolysis, as well as an effective strategy for rationally designing 2D NFs catalysts with high activity and durability. [Display omitted] • Stabilized cobalt-based nanofilm exhibit outstanding activity for NaBH 4 hydrolysis • Cobalt-based nanofilm assists the activation of NaBH 4 and water molecules. • Carbon prevent the formation of Co(OH) 2 and avoid the loss of active Co The design and construction of transition metal catalysts with high performance and low-cost characteristics are imperative for liquid hydrogen storage materials. In this study, we prepared ultrathin carbon-stabilized Co-doped Co x O y nanofilms (C–Co/Co x O y NFs) using an ionic liquid/water interface strategy for sodium borohydride (NaBH 4) hydrolysis. Owing to its two-dimensional (2D) NF structure and the protective effects of the composite carbon, the C–Co/Co x O y NF catalyst exhibited remarkable activity and durability for hydrogen generation from NaBH 4 hydrolysis. The hydrogen generation rate reached 8055 mL·min−1·g Co −1 (5106 mL·min−1·g Cat −1) and the catalyst could be recycled more than 20 times, surpassing most reported metal-based catalysts under comparable conditions. In addition, the exceptional 2D Co-based NF structures, with numerous active sites, assisted in the activation of NaBH 4 and water molecules, promoting hydrogen production. Thus, these results provided an in-depth understanding of hydrogen generation from NaBH 4 hydrolysis, and an effective strategy for rationally designing highly active and durable 2D NF catalysts. [ABSTRACT FROM AUTHOR]

The purpose was to report the short-term outcomes and survival of hemiarthroplasty with a pyrocarbon head (HA-PYC) for the treatment of shoulder osteoarthritis in patients aged ≤ 60 years. We hypothesized that HA-PYC could be an alternative to hemi-metal (avoiding the risk of rapid glenoid erosion) and total shoulder arthroplasty (TSA) (avoiding the risk of rapid glenoid loosening) in an active patient population. Sixty-four consecutive patients (mean age, 53 years) who underwent HA-PYC for glenohumeral osteoarthritis were included. The primary outcome was revision to TSA or reverse shoulder arthroplasty. Secondary outcome measures included functional outcome scores; return to work and sports; and radiographic evaluation of humeral reconstruction quality using the "circle method" of Mears, as well as glenoid erosion severity and progression using the Sperling classification. Patients were reviewed and underwent radiography at an average follow-up of 33 months (range, 24-60 months). At last follow-up, the rate of survival of the HA-PYC prosthesis was 92%. Revision was performed in 5 patients, with a mean delay of 24 months (range, 15-37 months): 1 conversion to TSA and 4 conversions to reverse shoulder arthroplasty. The Constant score and Subjective Shoulder Value increased from 36 points (range, 26-50 points) to 75 points (range, 69-81 points) and from 35% (range, 20%-50%) to 80% (range, 75%-90%), respectively (P <.001). Postoperatively, 91% of the patients (42 of 46) returned to work and 88% (15 of 17) returned to sport. The severity of preoperative and postoperative glenoid wear (Sperling grade 3 or 4) had no influence on the functional results. Patients who underwent associated concentric glenoid reaming (n = 23) had similar Constant scores and Subjective Shoulder Values (P =.95) to other patients and did not show more progression of glenoid wear. Nonanatomic reconstruction of the proximal humerus (center of rotation of the prosthesis > 3 mm from the anatomic center) occurred in 29% (18 of 62 patients) and was associated with significantly lower functional and subjective results, more complications (subscapularis insufficiency and/or symptomatic glenoid erosion), and a higher risk of revision. The additional 1.5-mm thickness of the metal disc under the pyrocarbon head was found to be the main reason for oversizing of the prosthetic head. HA-PYC is a reliable procedure to treat shoulder osteoarthritis and allows return to work and sports in a young (≤60 years) and active patient population. The severity of glenoid bone erosion or the association with glenoid reaming does not affect functional outcomes and failure risk. By contrast, nonanatomic reconstruction of the proximal humerus after HA-PYC (because of humeral head oversizing) occurred in one-third of the cases and is associated with lower functional outcomes, as well as higher risks of complications and revision. [ABSTRACT FROM AUTHOR]

A highly sensitive amperometric Prussian blue‐based hydrogen peroxide sensor was developed using 3D pyrolytic carbon microelectrodes. A 3D printed multielectrode electrochemical cell enabled simultaneous highly reproducible Prussian blue modification on multiple carbon electrodes. The effect of oxygen plasma pre‐treatment and deposition time on Prussian blue electrodeposition was studied. The amperometric response of 2D and 3D sensors to the addition of hydrogen peroxide in μM and sub‐μM concentrations in phosphate buffer was investigated. A high sensitivity comparable to flow injection systems and a detection limit of 0.16 μM was demonstrated with 3D pyrolytic carbon microelectrodes at stirred batch condition [ABSTRACT FROM AUTHOR]

A series of pyrolytic carbon–silicon carbide (PyC–SiC) composites were prepared by the co-deposition method. The effects of pyrolysis temperature, H2 concentration and residence time on the microstructure, surface morphology and composition of fabricated composites were investigated. The energy-dispersive X-ray spectroscopy results showed that by increasing the residence time from 2.4 to 4.2 s, the Si content of the composites was increased from 20 to 259%. Also, the Si content of the composites was increased from 2 to 25% by increasing the temperature from 800 to 1100 °C. The Si amount of PyC–SiC was decreased by the addition of H2 gas to the stream of feed (2% for 12.5 vol% H2 gas and 25% for 0 vol% H2). Scanning electron microscopy showed that the surface uniformity of the composites was decreased by increasing the H2 concentration, and decreasing the temperature and residence time. X-ray diffraction analysis showed that the in-plane crystal size (La) of composites was changed by varying residence time, H2 concentration, and temperature. The results of the thermogravimetric analysis showed that the oxidation temperature of composites increased by increasing the amount of the embedded silicon in the composites (about 20–110 °C). Furthermore, the wear resistance of the PyC–SiC composites increased by increasing the silicon amounts (about 5–200%). The oxidation temperature and wear resistance of the composites were also improved by increasing the temperature and the residence time and decreasing the H2 concentration. [ABSTRACT FROM AUTHOR]