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The extensive utilization of bismuth and its derivatives in many industries, such as chemical, semiconductor, pharmaceutical, and cosmetics, leads to their accumulation in wastewater, posing a risk to both human health and the environment. Carbon nanorods (CNR) are fluorescent nanoparticles with an ability to detect various analytes as sensing probes. This study focuses on the production, structure, and chemical composition characterization of silkworm-derived CNR (swCNR) and their ability to detect bismuth ions (Bi3+) and inhibit radicals. The optimum wavelength for exciting the fluorescence of swCNR was 370 nm, and the resulting emission peak was observed at 436 nm. The prepared swCNR showed static fluorescence quenching mechanism-based sensing of Bi3+ ions with a limit of detection of 175 nM and two linear ranges from 0.5 to 5 µM (R2 = 0.9997) and 10-50 µM (R2 = 0.9995). The swCNR demonstrated high selectivity in detecting Bi3+ ions in the spiked river water samples, thus establishing the swCNR's role as a nano fluorescence probe designed for the selective detection of Bi3+ ions among other metal ions. Favorable results for the antiradical ability of swCNR were obtained against hydroxyl, 2,2 diphenyl-1 picrylhydrazyl, and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radicals with scavenging percentages of 15, 32, and 90, respectively. The possible applications of swCNR in the environmental and antioxidant sectors are proposed in this study.

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Developing highly efficient bi-functional noble-metal-free oxygen electrocatalysts with low-cost and scalable synthesis approach is challenging for zinc-air batteries (ZABs). Due to the flexible valence state of manganese, MnF2 is expected to provide efficient OER. However, its insulating properties may inhibit its OER process to a certain degree. Herein, during the process of converting the manganese source in the precursor of porous carbon nanofibers (PCNFs) to manganese fluoride, the manganese source is changed to manganese acetate, which allows PCNFs to grow a large number of hollow carbon nanorods (HCNRs). Meanwhile, manganese fluoride will transform from the aggregation state into uniformly dispersed MnF2 nanodots, thereby achieving highly efficient OER catalytic activity. Furthermore, the intrinsic ORR catalytic activity of the HCNRs/MnF2 @PCNFs can be enhanced due to the charge modulation effect of MnF2 nanodots inside HCNR. In addition, the HCNRs stretched toward the liquid electrolyte can increase the capture capacity of dissolved oxygen and protect the inner MnF2 , thereby enhancing the stability of HCNRs/MnF2 @PCNFs for the oxygen electrocatalytic process. MnF2 surface-modulated HCNRs can strongly enhance ORR activity, and the uniformly dispersed MnF2 can also provide higher OER activity. Thus, the prepared HCNRs/MnF2 @PCNFs obtain efficient bifunctional oxygen catalytic ability and high-performance rechargeable ZABs.

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Owing to the high demand for clean and renewable energy technologies, several studies have focused on developing economically feasible, highly effective, and stable non-precious electrocatalysts for promoting the oxygen evolution reaction (OER). This development has stimulated an expansion of investigative quests and indicated the importance of advancing electrocatalytic research in this field. Through a facile and efficient method, Ni nanoparticles were uniformly embedded into nanoporous carbon nanorods (Ni-NCN), which are subsequently electrodeposited on CoFe-layered double hydroxide (LDH) nanosheets to produce highly efficient Ni-NCN/CoFe-LDH composites used for OER. The composite exhibited excellent catalytic activity toward OER owing to its low overpotential (ƞ10 mA = 280 mV), small Tafel slope (42 mV dec-1), and excellent durability. The Ni-NCN/CoFe-LDH catalyst exhibited higher OER activity owing to its uniformly dispersed Ni nanoparticles, large specific surface area, enhanced electron transport, and synergistic effect of multiple composites. Additionally, the enhanced synergistic effect of Ni-NCN promoted higher OER performance compared with Ni-undoped carbon nanorod/LDH, indicating that the Ni dopant and LDH significantly contributed to the overall OER performance. The synergistic effect of multiple composites significantly contributed to the excellent OER performance, indicating their potential as OER catalyst.

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Insufficient glucose control remains a critical challenge for type 2 diabetes mellitus (T2DM) patients with currently used therapeutic drugs, which can also have detrimental side effects. The facile synthesis of nitrogen-doped carbon nanorods (N-CNRs) as therapeutic agents in a T2DM transgenic db/db mouse model is reported herein. N-CNRs are synthesized from silkworm powder without the assistance of any template and possess a hollow graphitic nature, rough surface, and good aqueous solubility, which make them ideal candidates for fabricating nanomedicines. N-CNRs are employed to reduce fasting blood glucose and ameliorate serum biomarker levels linked to oxidative stress and inflammation. Interestingly, through the downregulation of enhanced expression of glutathione peroxidase, superoxide dismutase, and catalase as well as inflammatory responses, N-CNRs reverse pancreatic dysfunction and normalize the secretory functions of pancreatic cells. Moreover, hepatic steatosis is attenuated by downregulating lipogenesis and increasing fatty acid oxidation. This finding may help in designing novel therapeutics for T2DM treatment.

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The hydrogen evolution reaction (HER) as a fundamental process in electrocatalysis plays a significant role in clean energy technologies. For an energy-efficient HER, it demands an effective, durable, and low-cost catalyst to trigger proton reduction with minimal overpotential and fast kinetics. Here, we successfully fabricate a highly efficient HER catalyst of N-C/Co/Mo2C holey nanorods with Co/ß-Mo2C nanoparticles uniformly embedded in nitrogen-doped carbon (N-C/Co/Mo2C) by pyrolyzing the molybdate-coordinated zeolitic imidazolate framework (ZIF-67/MoO42-) holey nanorods, which result from the reaction between CoMoO4 and MeIM in a methanol/water/triethylamine mixed solution. The uniform distribution of MoO42- in the ZIF-67/MoO42- enables Co/ß-Mo2C nanoparticles to be well-distributed within nitrogen-doped carbon holey nanorods. This synthetic strategy endows the N-C/Co/Mo2C catalyst with uniformly decorated bimetal, thus attaining excellent HER electrocatalytic activities with a small overpotential of 142.0 mV at 10 mA cm-2 and superior stability in 1.0 mol L-1 KOH aqueous solution.

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Transition metal doped carbon materials are recognized as promising sensing platforms for glucose detection. Herein, a simple strategy involving crystallinity, nanostructure engineering, and pyrolysis was developed for constructing well-defined Ni nanoparticle embedded on nanoporous carbon nanorods (Ni/NCNs). A three-dimensional nickel-based metal-organic framework (Ni-MOF) was used as both a self-sacrificing template and precursor. Due to the synergistic effects between the uniformly dispersed Ni nanoparticles and the nanoporous carbon matrix, the as-prepared Ni/NCNs exhibited remarkable electrochemical activity. The fabricated Ni/NCNs glucose sensor showed excellent electrocatalytic performance with ultra-low limit of detection, wide linear detection ranges, fast response times (within 1.6 s), superior stability, and anti-interference characteristics. Moreover, the Ni/NCNs sensing platform was successfully applied to analyze glucose concentrations in human blood samples. These results showed that Ni/NCNs hold potential applications in developing enzyme-free glucose sensors.

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A universal anode material of 1D core-shell MoO2@MoS2/nitrogen-doped carbon (MoO2@MoS2/NC) nanorods has been elaborately synthesized via a facile fabrication route for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), in which MoO2 core not only acts as a conductive backbone for efficient electron transport, but creates structural disorders in MoS2 nanosheets to prevent aggregation and expose more active sites for alkali-ions. Meanwhile, the MoO2 core is tightly encapsulated by the parallelly aligned MoS2 nanosheets to constrain the size of crystals, which greatly shortens the ionic diffusion path and accelerates diffusion rate, thus ensuring fast reaction kinetics. Additionally, the resilient and conductive N-doped carbon matrix in the hybrid could maintain the structural integrity and enhance the electrical conductivity of the electrodes, improving the rate capability and life span. The flexible 1D nanorods could contract freely during the charge/discharge process, further assuring the structural stability of the electrodes. Benefiting from the above-mentioned advantages, the MoO2@MoS2/NC electrodes still remains a specific capacity of 583.5 mA h g-1 after 1500 cycles at a high current density up to 10 A g-1 in LIBs, and a capacity of 419.8 mA h g-1 is steadily kept over 800 cycles at 2 A g-1 in SIBs.

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Magnetic hierarchical nickel/nickel oxide/carbon nanorods (Ni/NiO@C) were prepared via the pyrolysis of a metal-organic framework containing nickel(II) nickel (Ni-MOF; Ni3(BTC)2) under argon atmosphere. In this material, magnetic Ni/NiO@C nanoparticles are embedded in porous carbon nanorods, and the morphology is similar to that of the original Ni-MOF precursor. The synthesized nanorods were applied as magnetic sorbents in the solid-phase extraction of five benzoylurea insecticides (flufenoxuron, chlorbenzuron, teflubenzuron, diflubenzuron and triflumuron), and their performance was evaluated under optimized conditions. The results show that the material exhibits high extraction recoveries from spiked samples (82.9%-107.6%) and linear response in the range of 0.2-450 µg·L-1. It is also characterized by relatively low limits of detection (50-100 ng·mL-1) at a signal-to-noise ratio of 3. The sorbent is chemically stable and can be repeatedly recycled, with little decline in extraction capacity after 20 cycles of reuse. The method was successfully applied to the quantification of benzoylureas in tea, wolfberry, millet, and oat samples, and it showed high extraction efficiency. Graphical abstractSchematic representation of the synthesis of magnetic hierarchical nickel/nickel oxide/carbon nanorods derived from Ni-MOF. The material is employed as a sorbent for the magnetic solid-phase extraction of benzoylurea insecticides.

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We realized the synthesis of carbon nanorods-monodisperse colloidal particles with a length of 50 nm and a width of 20 nm-which can be considered an addition to the family of light-emitting carbon-based nanostructures. Their anisotropic shape is determined by the use of the surfactant aminopropylisobutyl polyhedral oligomeric silsesquioxane, and their optical properties originate from domains of polycyclic aromatic hydrocarbons incorporated within an inorganic framework. The nanorods show dual polarized emission with a quantum yield of 15-20% and emission anisotropy of ∼0.3, which changes from blue (460 nm) to yellow (565 nm) depending on the excitation wavelength. These carbon nanorods expand the range of light-emitting carbon nanomaterials available for optoelectronic and biolabeling applications.

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Cobalt-modified molybdenum dioxide nanoparticles highly dispersed on nitrogen-doped carbon nanorods (Co-MoO2/NCND), are synthesized from anilinium trimolybdate dihydrate nanorods, for the performance improvement of microbial fuel cell based on a mixed bacterial culture. Electrochemical measurements demonstrate that the as-synthesized Co-MoO2/NCND exhibits excellent electrocatalytic activity for the charge transfer on anode, providing the cell with a maximum power density of 2.06 ±â€¯0.05 W m-2, which is strikingly higher than the bare carbon felt anode (0.49 ±â€¯0.04 W m-2). The excellent performance of Co-MoO2/NCND is ascribed to the increased electronic conductivity of carbon nanorods by N-doping, the high ability of MoO2 to enrich electroactive bacteria, as demonstrated by high-throughput sequencing, and the enhanced activity of MoO2 by Co-modifying toward redox reactions in electroactive bacteria. This report provides a new concept of anode electrocatalyst fabrications for the application of microbial fuel cells in electricity generation and wastewater treatment.

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Bismuth (Bi)-based electrodes are highly attractive for potassium-ion batteries (PIBs) while suffering from a short cycle life due to the larger diameter of K ion, leading to unstable solid electrolyte interface (SEI) films during continuous potassiation/depotassiation. Herein, we developed novel ultrathin carbon film@carbon nanorods@Bi nanoparticle (UCF@CNs@BiN) materials for the long cycle life anode of PIBs. Bi nanoparticles are uniformly distributed in carbon nanorods, which not only provides a high-speed channel for ion transport but also accommodates the volume change of Bi nanoparticles during continuous potassiation/depotassiation processes. The UCF@CN matrix can direct most SEI film formation on the surface of the carbon film, not on the surface of individual Bi nanoparticles, avoiding the fracture of the matrix. Benefiting from their unique structure, the UCF@CNs@BiN anodes exhibit an outstanding capacity of ∼425 mAh g-1 at 100 mA g-1 and a capacity decay of 0.038% per cycle over 600 cycles. Even at a higher current density of 1000 mA g-1, there is a capacity decay as low as 0.036% per cycle during 700 cycles. Meanwhile, this work provides a new way of utilizing the metal-organic framework structure and reveals a highly promising PIB anode.

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Hierarchical superstructures in nano/microsize have attracted great attention owing to their wide potential applications. Herein, a self-templated strategy is presented for the synthesis of a spherical superstructure of carbon nanorods (SS-CNR) in micrometers through the morphology-preserved thermal transformation of a spherical superstructure of metal-organic framework nanorods (SS-MOFNR). The self-ordered SS-MOFNR with a chestnut-shell-like superstructure composed of 1D MOF nanorods on the shell is synthesized by a hydrothermal transformation process from crystalline MOF nanoparticles. After carbonization in argon, the hierarchical SS-MOFNR transforms into SS-CNR, which preserves the original chestnut-shell-like superstructure with 1D porous carbon nanorods on the shell. Taking the advantage of this functional superstructure, SS-CNR immobilized with ultrafine palladium (Pd) nanoparticles (Pd@SS-CNR) exhibits excellent catalytic activity for formic acid dehydrogenation. This synthetic strategy provides a facile method to synthesize uniform spherical superstructures constructed from 1D MOF nanorods or carbon nanorods for applications in catalysis and energy storage.

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The data presented in this article are related to the research article entitled "Novel controlled synthesis of nanoporous carbon nanorods from resorcinol-formaldehyde xerogels" (Awadallah-F and Al-Muhtaseb, 2017) [1]. This article describes the novel controlled approach of nanoporous carbon nanorods synthesis from resorcinol/formaldehyde xerogels. The field dataset is made publicly available to enable critical or extended analyzes.

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Dopamine is a neurotransmitter that modulates arousal and motivation in humans and animals. It plays a central role in the brain "reward" system. Its dysregulation is involved in several debilitating disorders such as addiction, depression, Parkinson's disease, and schizophrenia. Dopamine neurotransmission and its reuptake in extracellular space takes place with millisecond temporal and nanometer spatial resolution. Novel nanoscale electrodes are needed with superior sensitivity and improved spatial resolution to gain an improved understanding of dopamine dysregulation. We report on a scalable fabrication of dopamine neurochemical probes of a nanostructured glassy carbon that is smaller than any existing dopamine sensor and arrays of more than 6000 nanorod probes. We also report on the electrochemical dopamine sensing of the glassy carbon nanorod electrode. Compared with a carbon fiber, the nanostructured glassy carbon nanorods provide about 2× higher sensitivity per unit area for dopamine sensing and more than 5× higher signal per unit area at low concentration of dopamine, with comparable LOD and time response. These glassy carbon nanorods were fabricated by pyrolysis of a lithographically defined polymeric nanostructure with an industry standard semiconductor fabrication infrastructure. The scalable fabrication strategy offers the potential to integrate these nanoscale carbon rods with an integrated circuit control system and with other complementary metal oxide semiconductor (CMOS) compatible sensors.

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As promising precious metal-free oxygen reduction reaction (ORR) electrocatalysts, Fe-N-C catalysts still face a great challenge to meet the requirement of practical applications. In this study, Fe, S, N-codoped hollow and porous carbon nanorods (Fe-S-N HPCNRs) were designed with the aim of improving the performance of Fe-N-C catalysts from the perspective of composition and structure. They were successfully prepared using cysteine, Fe2+ salt, and polydopamine-encapsulated ZnO nanorods (ZnO NRs@PDA) as precursors by a pyrolysis-acid etching strategy. The hollow and porous structure and composition of Fe, S, N, and C were verified by transmission electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller, and X-ray photoelectron spectroscopy tests. At the optimum ratio of ZnO NRs@PDA/cysteine and pyrolysis temperature, the Fe-S-N HPCNRs display higher ORR activities than the control samples which are lack of one of the precursors. Electrochemical tests show that the ORR follows a 4e pathway with the Fe-S-N HPCNRs. In addition, the long-term stability and methanol tolerance of Fe-S-N HPCNRs are good and superior to those of 20 wt % Pt/C.