Environment-friendly organic coordination design of Z-scheme heterojunction N-BOB/BiOIO3 for efficient LED-light-driven photocatalytic and electrochemical performance.

As the climate seriously changes, ecofriendly nanomaterials have attracted tremendous interest in renewable energy as photocatalysis. Herein, we designed a new green bismuth-based Z-scheme Bi2O22+ slabs coordinate with 2-aminoterephthalic acid (N-BOB)/BiOIO3 through a simple anion exchange and postsynthetic hydrothermal reaction. FTIR, XRD, FESEM and TEM were employed to characterize the functional groups, structure, and morphologies. UV-DRS revealed the difference in band energy of the N-BOB and N-BOB/BiOIO3. Toward Rh B, TC and CIP degradation tests, 1-N-BOB/BiOIO3 manifests the best photocatalytic degradation (52.3%, 63.6% and 30.2%) efficiency. Also, 1-N-BOB/BiOIO3 possesses high durability in photocatalytic reactions and can inhibit 32.3% of bacterial growth. The results indicate that the synergistic effect between surface amine groups and Z-scheme heterojunction harvests light absorption to increase solar-to-energy (STE) efficiency, accelerate the charge separation, and increases the active sites with high photoredox potential, thus improving the photocatalytic performance. ROS scavenging tests further elucidated that photogenerated holes and hydroxyl radicals play a critical role. In addition, the surface amine groups and benzene rings can be utilized for supercapacitors and other multidisciplinary applications. 0.5 N-BOB/BiOIO3/GO impressively showed 5 times higher specific capacitance than pure GO electrode. We hope this work provides new sight into designing green nanomaterials to relieve environmental pollution and leave behind a clean future for the next generation.

Preparation of Ni(OH)2/CuO heterostructures for improved photocatalytic degradation of organic pollutants and microorganism.

In this study, the Ni(OH)2/CuO heterostructured photocatalysts have been prepared via microwave (MW) hydrothermal method. The results indicate that the Ni(OH)2/CuO heterostructured composite exhibits a strong absorption in the UV and Vis regions. The construction of the heterojunction also improves the photogenerated carrier transport and inhibits the electron-hole separation due to the enhanced absorbance and the well alignment of the energy band at the Ni(OH)2/CuO interface. The photocatalytic capability of the heterostructured composites with different Ni(OH)2/CuO molar ratios is evaluated by the photodegradation of methylene blue under visible light illumination. The results reveal that the Ni(OH)2/CuO (1:1) heterostructures show the best photocatalytic efficiency, which is 2.18 and 6.13 times higher than that of pure Ni(OH)2 and CuO, respectively. Besides, the Ni(OH)2/CuO composites also reveal remarkable biocompatibility and strong photocatalytic activity in the degradation of antibiotics such as ciprofloxacin (CIP) and tetracycline (TC) and inactivation of Escherichia coli (E. coli).

Bio-Phenolic Resin Derived Porous Carbon Materials for High-Performance Lithium-Ion Capacitor.

In this article, hierarchical porous carbon (HPC) with high surface area of 1604.9 m2/g is prepared by the pyrolysis of rubberwood sawdust using CaCO3 as a hard template. The bio-oil pyrolyzed from the rubber sawdust, followed by the polymerization reaction to form resole phenolic resin, can be used as a carbon source to prepare HPC. The biomass-derived HPC shows a three-dimensionally interconnected morphology which can offer a continuous pathway for ionic transport. The symmetrical supercapacitors based on the as-prepared HPC were tested in 1.0 M tetraethylammonium tetrafluoroborate/propylene carbonate electrolyte. The results of electrochemical analysis show that the HPC-based supercapacitor exhibits a high specific capacitance of 113.3 F/g at 0.5 A/g with superior rate capability and cycling stability up to 5000 cycles. Hybrid lithium-ion capacitors (LICs) based on the HPC and Li4Ti5O12 (LTO) were also fabricated. The LICs have a maximum energy density of 113.3 Wh/kg at a power density of 281 W/kg. Moreover, the LIC also displays a remarkable cycling performance with a retention of 92.8% after 3000 cycles at a large current density of 0.75 A/g, suggesting great potential application in the energy storage of the LIC.

Versatile Functionalization of P25 Conjugated ND Nanocomposites for UV-Mediated Free Radical Scavenging and Facilitates Anti-Inflammation Potential in Human Cells.

In this work, we demonstrated that building different linking groups between nanodiamond (ND) and TiO2 (P25) could provide more effective protection under oxidative stress and ultraviolet (UV) light irradiation compared with the use of TiO2 alone. The establishment of ester (-C-O-O-R), amide (-CONH-), and epoxide-amine adduct (-NHCCO-) groups between ND-TiO2 composites was found to be critical in the generation of reactive oxygen species (ROS) by controlling their charge transfer behaviors. We hypothesized that linking groups between the composites dictate the performance of ROS generation from nano-TiO2 under UV-light irradiation due to the differences in linking groups. The results showed that hydroxyl radicals were attenuated by the incorporation of ND. An MTT cell proliferation assay was performed in human cells under the treatment of ND-TiO2 composites to investigate the impacts of composites on cell viability. The results from the luciferase reporter assay suggested they have anti-inflammatory activity and can reduce cellular DNA damage under ROS stimulation. A zebrafish model was also applied with the ND-TiO2 composite treatment to demonstrate the safety aspects of the composites in vivo and their biomedical application potential. Studies exploring ROS generation behaviors in different linking groups suggested that interactive functionalization between nanoparticles might be an ideal antioxidant and anti-inflammatory strategy.

Co2+-Doped BiOBrxCl1-x hierarchical microspheres display enhanced visible-light photocatalytic performance in the degradation of rhodamine B and antibiotics and the inactivation of E. coli.

In this article, we have synthesized Co2+-doped BiOBrxCl1-x hierarchical nanostructured microspheres, featuring different degrees of Co2+ doping, displaying excellent photocatalytic performance. X-ray diffraction and Raman spectroscopy indicated that the Co2+ ions were successfully doped into the BiOBrxCl1-x nanocrystals. The photodegradation rate of rhodamine B mediated by a doped BiOBrxCl1-x was 150 % greater than that of the non-doped BiOBr. We ascribe the improved photocatalytic capability of the Co2+-doped BiOBrxCl1-x to a combination of its superior degree of light absorption, more efficient carrier separation, and faster interfacial charge migration. The major active species involved in the photodegradation of RhB also has been investigated. Moreover, the doped BiOBrxCl1-x possessed excellent cellular biocompatibility and displayed remarkable performance in the photocatalytic bacterial inactivation.

Simultaneous formation of Bi2O2(OH)(NO3)/BiOBr ultrathin hierarchical microspheres for effectively promoting visible-light-driven photocatalytic activity in environmental remediation.

As a two-dimensional nanomaterial, bismuth oxybromide (BiOBr) have attracted tremendous interest in the area of visible-light photocatalysis since it can provide the internal electric field (IEF) through z-axis through its unique electronic band structure. However, the insufficient active sites and rapid recombination rate of charged carriers hamper the efficiency of the photocatalysis. To address these two major obstacles, an enticing strategy of constructing heterojunction was established by introducing Bi2O2(OH)(NO3) (BiON) in BiOBr with the same precursor. Through a facile one-pot hydrothermal synthesis, two Sillén-type layered photocatalysts, with intimately constructed ultrathin heterostructure, was synthesized by the co-precipitation method. In this work, the formation of Bismuth-based heterojunction for charge separation is established by the excessive bismuth nitrate, which subsequently participates with the in situ growth of ultrathin hierarchical microspheres. By attenuating the thickness of BiOBr from 20 nm to 8 nm with the aid of BiON, the photogenerated charges could migrate to the active sites through shorter charge diffusion pathway. Also, the BiOBr and BiON act as an active bridge to promote the separation of electron-hole pairs, which also brings out more active sites due to its increased specific surface area. BiON/BiOBr ultrathin hierarchical microspheres exhibited enhanced visible-light photocatalytic activity for decontaminating several types of pollutants. Besides, the activity of as-prepared BiON/BiOBr was further evaluated by inhibiting the growth of kanamycin-resistant bacteria strains. This study presents a novel strategy to incorporate the crystalline bismuth hydrate nitrate into BiOBr to form ultrathin hierarchical microspheres with high surface area for environmental remediation.

Intercalating pyrene with polypeptide as a novel self-assembly nano-carrier for colon cancer suppression in vitro and in vivo.

Giving patients right dosage is an essential concept of precision medicine. Most of nanocarriers lack of flexible drug capacity and structural stability to be customized for specific treatment, resulting in low therapeutic efficacy and unexpected side effects. Thus, a growing need emerges for fast and rigorous approaches to develop nanoparticles with properties of adjustable dosage and controllable particle size. Poly-l-Lysine is known for its enhanced bioadhesivity and pH-triggered structural swelling effect, which is utilized as the main agent to activate the multistage drug releasing. Inspired by natural bio-assembly system, we report a simple method to self-assemble Poly-l-Lysine-based nanoparticles via supramolecular recognitions of cross-linked pyrenes, which provides noncovalent force to flexibly encapsulate Doxorubincin and to construct robust nanostructures. Pyrene-modified polypeptide self-assemblies are able to adjust drug payload from 1: 10 to 2:1 (drug: polypeptide) without changing its uniform nano-spherical morphology. This nanostructure remained the as-made morphology even after experiencing the long-term (~ 10 weeks) storage at room temperature. Also, the nanoparticles displayed multi-step drug release behaviours and exhibited great in vitro and in vivo cytotoxicity towards colon cancer cells. The as-mentioned nanoparticles provide a novel perspective to compensate the clinical needs of specific drug feedings and scalable synthesis with advantages of simple-synthesis, size-adaptivity, and morphology reversibility.

GFP Plasmid and Chemoreagent Conjugated with Graphene Quantum Dots as a Novel Gene Delivery Platform for Colon Cancer Inhibition In Vitro and In Vivo.

Scientists have studied intensively the gene delivery carriers for treating genetic diseases. However, there are challenges that impede the application of naked gene-based therapy at the clinical level, such as quick elimination of the circulation, lack of membrane penetrability, and poor endosome trapping. Herein, we develop graphene quantum dots (GQDs)-derivative nanocarriers and introduce polyethylenimine (PEI) to equip the system with enhanced biocompatibility and abundant functional groups for modification. In addition to carrying green fluorescent protein (GFP) as an example of gene delivery, this system covalently binds colon cancer cells targeted antibody and epidermal growth factor receptor (EGFR) to enhance cell membrane penetrability and cell uptake of nanocarriers. To achieve multistrategy cancer therapy, the anticancer drug doxorubicin (Dox) is noncovalently encapsulated to achieve pH-induced drug release at tumor sites and leaves space for further functional gene modification. This nanoparticle serves as a multifunctional gene delivery system, which facilitates improved cytotoxicity and longer-sustained inhibition capacity compared to free Dox treatments in colon cancer cells. Moreover, our GQD composites display compatible tumor suppression ability compared with the free Dox treatment group in xenograft mice experiment with significantly less toxicity. This GQD nanoplatform was demonstrated as a multifunctional gene delivery system that could contribute to treating other genetic diseases in the future.

Doxorubicin conjugated AuNP/biopolymer composites facilitate cell cycle regulation and exhibit superior tumor suppression potential in KRAS mutant colorectal cancer.

Colorectal cancer is a leading cause of death in the world. Despite the progress in therapeutic development, there are still challenges in clinical practice. Nanomedicine has emerged as a solution to enhance traditional therapy. Gold nanoparticles (AuNP) have been demonstrated as potential appliance in treating cancers, yet few studies investigated the capacity of biopolymer-conjugated AuNP in colon cancer as well as examined the system in both cancer cell line and animal models. In this study, we designed the AuNP/biopolymer composite therapeutic system with a chemotherapy agent, doxorubicin (DOX). Two composites with different drug load were applied (referred to as AuPPPyA and AuPPPyB). The composites were characterized by UV spectrum, transmission electron microscope (TEM), zeta potential measurement, and cell cycle analysis. Both therapeutic systems exhibited superior cytotoxic effects compared to DOX alone group. Compatible results were also demonstrated in vivo, as tumor inhibition rate were 46.2% in AuPPPyA and 66.4% in AuPPPyB, which were both higher than that of DOX alone (30%). Cell cycle regulation mediated by our composites was also examined in our study. In conclusion, our data demonstrated that AuNP/biopolymer composites are powerful in treating KRAS gene mutated colorectal cancer, and the system could potentially contribute to other clinical refractory diseases in the future.

Carboxylated carbon nanomaterials in cell cycle and apoptotic cell death regulation.

Carbon nanomaterials, include carbon nanotubes and graphene nanosheets, have drawn an increasing amount of attention because of their potential applications in daily life or in providing novel therapeutic possibilities for treating diseases. However, the overall biocompatibility, the potential toxic effects of carbon nanomaterials toward human cells, and their modulations in cellular mechanism, are not fully understood. Herein, four types of carbon nanomaterials, include long and short carbon nanotubes and graphene nanosheets, at low and high concentrations, were functionalized and dispersed in the biocompatible buffer for assessment. The surface structure, the morphology, and chemical composition of carbon nanomaterials were characterized. Also, biological assays investigating cellular viability, vitality, cell cycle, and apoptotic cell death were applied on cells co-incubated with nanomaterials, to evaluate the biocompatibility of these nanomaterials in human cells. Our data suggested that even though co-incubation of nanomaterials did not seem to affect the viability of cells notably, high concentrations (50 ug/ml) of SW could lead to unhealthy cells, and we observed dramatic G2 arrest effect mediated by p21 induction in high SW incubated cells. Other nanomaterials at high concentration may also alter cell cycle profile of the cells. In summary, our data demonstrated that these nanomaterials could regulate cell cycle and lead to apoptosis at high concentrations, and the underling molecular mechanisms have been addressed. Caution should be taken on their concentration when nanomaterials are in used in future medical applications.

Refluxed Esterification of Fullerene-Conjugated P25 TiO2 Promotes Free Radical Scavenging Capacity and Facilitates Antiaging Potentials in Human Cells.

Titanium dioxide nanomaterials have good capability to prevent human cells from damage under UV irradiation. However, some studies indicated that the nanoscale of titanium dioxide could potentially cause harmful effects such as free radical generation under UV irradiation and thereby accelerate the progress of cell aging. Fullerenes can scavenge large amounts of free radicals due to the fact that fullerenes contain enormous amount of π electrons with low lying lowest unoccupied molecular orbital, but its adverse properties, such as the poor solubility in water, restricted the applicability. In this study, we employed water-soluble carboxylic acid fullerenes (C60-COOH and C70-COOH) as the free radical scavenger and modify onto the surface of titanium dioxide by refluxed esterification (P25/C60-COOH or C70-COOH) technique. The conformation and properties of these nanomaterials were characterized by techniques and equipment such as X-ray diffraction, energy dispersive spectroscopy analysis, scanning electron microscopy, thermal gravimetric analysis, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy. We also introduced methylene blue and rhodamine B as indicators to evaluate and demonstrate the scavenging capacity of these nanomaterials. Moreover, we examined the biocompatibility and UV protection capacity of our P25/fullerene composites in human 293T cells, and applied luciferase activity assay to investigate the possible underlying cell protection mechanisms exhibited by these nanomaterials. Our data indicate that both P25/C60-COOH and P25/C70-COOH could protect human cells against UV exposure. P25/C70-COOH exhibits great anti-inflammation capacity, whereas P25/C60-COOH exhibits great anti-oxidative stress and anti-DNA damage capacity. Our results suggest that most of our P25/fullerene composite materials have the ability to reduce free radicals and exhibit high biomedical potential in anti-inflammation, anti-oxidant, and anti-aging applications.

Three-Dimensional Conductive Nanocomposites Based on Multiwalled Carbon Nanotube Networks and PEDOT:PSS as a Flexible Transparent Electrode for Optoelectronics.

We have synthesized conductive nanocomposites composed of multiwalled carbon nanotubes (MWCNTs) and Au nanoparticles (NPs). The Au NPs with an average size of approximately 4.3 nm are uniformly anchored on the MWCNT. After being exposed to microwave (MW) plasma irradiation, the anchored Au NPs melt and fuse, leading to larger aggregates (34 nm) that can connect the MWCNT forming a three-dimensional conducting network. The formation of a continuous MWCNT network can produce more a conductive pathway, leading to lower sheet resistance. When the Au-MWCNT is dispersed in the highly conductive polymer, poly(ethylene dioxythiophene):polystyrenesulfonate ( PEDOT: PSS), we can obtain solution-processable composite formulations for the preparation of a flexible transparent electrode. The resulting Au-MWCNT/PEDOT:PSS hybrid films possess a sheet resistance of 51 Ω/sq with a transmittance of 86.2% at 550 nm. We also fabricate flexible organic solar cells and electrochromic devices to demonstrate the potential use of the as-prepared composite electrodes. Compared with the indium tin oxide-based devices, both the solar cells and electrochromic devices with the composites incorporated as a transparent electrode deliver comparable performance.

Highly stable, solution-processable phenothiazine derivative as hole collection material for organic solar cells.

In this study, we have synthesized a solution-processable phenothiazine, 4-phenothiazin-10-yl-anisole (APS), as hole collection material in organic solar cells (OSCs). The APS reveals unique optical and electronic properties which can efficiently modify the work function (ΦW) of indium tin oxide (ITO) electrode to enhance the electron blocking capability. Moreover, the results indicate that the APS is highly air-stable which can significantly enhance the long-term stability of OCSs. The inverted device based on APS reached a power conversion efficiency (PCE) of 3.56% and exhibited much better stability under ambient conditions relative to that of the corresponding PEDOT:PSS based device.