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Objectives: The micro‐nano structure of 3D‐printed porous titanium (Ti) alloy with excellent performance in avoiding stress shielding and promoting bone tissue differentiation provides a new opportunity for the development of bone implants, but it necessitates higher requirements for bone tissue differentiation and the antibacterial properties of bone implants in clinical practice. Methods: This study investigated the preparation, antimicrobial properties, and osteogenesis‐promoting ability of the 3D printed porous Ti alloy anodic oxidized Ag‐carrying (Ag@3D‐TiO2) scaffolds. The 3D printed porous Ti alloy (3D‐Ti), anodized 3D printed porous Ti alloy (3D‐TiO2), and Ag@3D‐TiO2 scaffolds were synthesized using electron beam melting. The antimicrobial properties of the scaffolds were examined using antibacterial tests and their cytocompatibility was assessed using a cell proliferation assay and acridine orange/ethidium bromide (AO/EB) staining. In vitro cellular assays were used to investigate the effects of the scaffold microstructural features on cell activity, proliferation, and osteogenesis‐related genes and proteins. In vivo animal experiments were used to evaluate the anti‐inflammatory and osteogenesis‐promoting abilities of the scaffolds. Results: The Ag@3D‐TiO2 scaffolds exhibited sustained anti‐microbial activity over time, enhanced cell proliferation, facilitated osteogenic differentiation, and increased extracellular matrix mineralization. In addition, alkaline phosphatase (ALP), collagen type I (COL‐I), and osteocalcin (OCN)‐related genes and proteins were upregulated. In vivo animal implantation experiments, the anti‐inflammatory effect of the Ag@3D‐TiO2 scaffolds were observed using histology, and a large amount of fibrous connective tissue was present around it; the Ag@3D‐TiO2 scaffolds were more bio‐compatible with the surrounding tissues compared with 3D‐Ti and 3D‐TiO2; a large amount of uniformly distributed neoplastic bone tissue existed in their pores, and the chronic systemic toxicity test showed that the 3D‐Ti, 3D‐TiO2, and Ag@3D‐TiO2 scaffolds are biologically safe. Conclusion: The goal of this study was to create a scaffold that exhibits antimicrobial properties and can aid bone growth, making it highly suitable for use in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Activated carbons with different porosities derived from coffee, which prepared by the potassium hydroxide (KOH) activation method, are used as electrode for supercapacitors. The prepared materials indicated a well‐designed porous structure that provides countless adsorption sites, leading to high supercapacitor performance. Mesopores allow rapid diffusion of electrolyte ions, while micropores usually provide abundant adsorption sites for ions. Therefore, appropriate control over pore‐size distributions is a key factor for good electrochemical performance. The porosity and surface structure of activated coffee grounds (ACGs) are highly dependent on both the activation temperature and KOH/carbonized materials weight ratio. The ACGs were characterized using N2 adsorption at 77 K. The specific surface area increased from 1.75 to 3065 m2/g. Cyclic voltammetry and galvanostatic charge–discharge tests were employed in the evaluation of the electrochemical behavior of each sample. The ACG materials have a high specific capacitance of 127.8 F/g and cycle stability after 2500 cycles. [ABSTRACT FROM AUTHOR]

Conjugated polymers have attracted growing attention for versatile applications in energy storage due to their potential benefits including low‐cost processing, molecular tunability, environmental benignity, and high mechanical flexibility. In particular, polymer‐based organic electrode materials have shown significant progress in supercapacitor (SC) applications with superior electrochemical behaviors. The performances of SCs are closely related to the intrinsic characteristics of different polymers in the nanoscale and the morphological features of the polymer‐based electrode materials obtained by different fabrication techniques in the macroscale. This review summarizes the design and synthesis of both p‐type and n‐type conjugated polymers, highlighting the pros and cons of three synthesis techniques: electrochemical polymerization, chemical polymerization, and in situ polymerization. The performances of conjugated polymers in SCs, their cycling stabilities, and structure‐performance relationships are discussed. Moreover, the existing challenges and future directions of polymer‐based SCs are considered with respect to energy density, stability, and large‐scale production to promote commercialization. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride‐hexafluoropropylene (PVDF‐HFP) is a standard electrolyte membrane and binder material for lithium‐ion batteries (LIBs) because of the benefits of membrane formation and strong mechanical properties. Still, its use is limited due to unavoidable defects such as high crystallinity and poor electrochemical performance. In this paper, a larger specific surface area and three‐dimensional (3D) permeable lamellae carboxylated g‐C3N4 (HCN) were successfully prepared by HNO3 and introduced into the PVDF‐HFP to obtain a high‐performance composite separator. The wettability and electrolyte absorption of PVDF‐HFP separator can be improved through the carboxylated HCN. More crucially, because PVDF‐HFP has several active sites and low crystallinity, adding HCN can greatly increase the ionic conductivity of separators. The ionic conductivity of PH‐HCN at 25 °C is 0.52 S cm−1, 4.7 times higher than the initial PVDF‐HFP membrane, and the oxidation potential can reach 4.8 V. The assembled lithium‐ion batteries half‐cell has a capacity of 71 % at a 5 C rate and 94 % after 400 cycles at a 2 C rate. Therefore, the improved separator has the potential to be applied to high‐performance LIBs. [ABSTRACT FROM AUTHOR]

Hierarchical carbon foams ( HCFs) with micro-, meso-, and macropores were successfully synthesized via a two-step process: (1) polymerization in oil-in-water (O/W) emulsions without any hard templates and (2) carbonization at 850°C. With the aim of both enhancing the stability of the emulsion and forming a micro- and mesoporous structure during the carbonization process, potassium citrate was introduced in an aqueous solution of resorcinol and formaldehyde. A series of HCFs were fabricated by changing the mass ratio of potassium citrate to total carbon sources from 0.25 to 1.5. The effect of potassium citrate on the porous structure of HCFs was investigated through nitrogen sorption tests. The prepared HCFs exhibited well-developed porous structures of micro-, meso- and macropores and high surface areas. The structural characteristics of the HCFs, including pore size distribution, surface area, and porosity, were significantly dependent on the amount of potassium citrate. It was concluded that potassium citrate greatly contributed to the formation of carbon foams with nano-sized pore structures and high porosity. Interestingly, it was found that when the mass ratio of potassium citrate to total carbon sources was 0.5, the HCFs showed the highest specific surface area (~1360 m2/g). Furthermore, the capacitive performances of the HCFs were evaluated in a 6.0 M KOH aqueous solution using typical electrochemical methods such as cyclic voltammetry and galvanostatic charge/discharge tests. The capacitance of the HCFs tended to increase with the increase in surface area. In particular, the HCFs with the highest surface area also exhibited excellent electrochemical properties (high capacitance of 224 F/g at 1.0 A/g, high rate capability of 191 F/g at 10.0 A/g). These features may be attributed to both the resulting interconnected pore structure that is easily accessible to ions and the high surface area. We believe that this synthesis strategy can be easily extended to the preparation of hierarchical porous carbon materials with a desirable pore structure by tuning the organic monomer. [ABSTRACT FROM AUTHOR]

In this study, a simple one‐step hydrothermal synthesis of three‐element complex system photocatalyst technology is systematically studied. The results show that due to the complex heterojunction formed by titanium dioxide (TiO2), tungsten trioxide (WO3) and activated carbon (AC) and the strong adsorption performance of AC, the catalytic efficiency and cycle stability of the composite have been significantly improved. The excellent electron transport ability of AC is conducive to the separation of carriers, so that the electron transfer between AC/TiO2 and AC/WO3 can make it achieve a heterojunction effect similar to TiO2/WO3. The rich specific surface area of AC and the pores of the "labyrinth" structure can provide a higher concentration of degradable substances inside the catalyst, and the degraded substances are quickly transferred to the active site for degradation. Therefore, by controlling the mass ratio of AC/TiO2/WO3, a photocatalyst with high catalytic efficiency and strong cycle stability was successfully prepared (the degradation efficiency is above 95 %, and the degradation efficiency after 5 cycles is above 80 %). [ABSTRACT FROM AUTHOR]

Fe2O3, TiO2, TiO2‐Fe2O3 and TiO2‐Fe2O3/Cu nanomaterials were synthesized by hydrothermal methods. The crystal structure and chemical valence of the samples were characterized by X‐ray diffractometry (XRD), transmission electron microscopy (TEM), photoelectron spectroscopy (XPS) and ultraviolet‐visible diffuse reflectance spectroscopy (UV‐vis DRS). The results show that the TiO2‐Fe2O3/Cu nanocomposites have been successfully synthesized and have good UV‐Vis absorption properties. The electrocatalytic properties of the samples were characterized by cyclic voltammetry (CV), electrochemical impedance spectra(EIS) and Tafel polarization curve (Taf). The TiO2‐Fe2O3/Cu nanocomposites have the highest cathode potential and current density, and the charge transfer resistance in EIS is TiO2 > Fe2O3 > TiO2‐Fe2O3 > TiO2‐Fe2O3/Cu. It is indicated that TiO2‐Fe2O3/Cu nanocomposites had good electrocatalytic properties. Finally, the photocatalytic properties of Fe2O3, TiO2, TiO2‐Fe2O3 and TiO2‐Fe2O3/Cu for the degradation of methyl orange (MO) were studied under UV‐vis irradiation. The results show that the reaction rate constants k of TiO2‐Fe2O3/Cu is the relatively highest(12.91×10−3 min−1), indicating the synthetic of TiO2‐Fe2O3/Cu have good photocatalytic properties, which are due to the highest light utilization of TiO2‐Fe2O3/Cu and the best charge transfer performance. The TiO2‐Fe2O3/Cu nanocomposites were successfully synthesized by one‐step hydrothermal method.The presence of Fe element causes a large red shift in the UV‐visible absorption spectrum, Cu element could be benefit the charge separation. It is known from electrochemical and catalytic tests that the TiO2‐Fe2O3/Cu nanocomposites exhibit good photoelectrocatalytic activity. [ABSTRACT FROM AUTHOR]