Tengteng Jiang

Preparation of N-doped carbon quantum dots for highly sensitive detection of dopamine by an electrochemical method

A simple electrochemical biosensor was developed based on an N-doped carbon quantum dot (NCQD) modified glass carbon electrode (NCQD/GCE). The modified electrode displayed a good linear and broad response for the detection of dopamine (DA). The as-prepared biosensor also exhibited satisfactory selectivity even with interference of ascorbic acid (AA) and uric acid (UA). Inorganic ions also had no effect on detecting DA.

Facile preparation of novel Au–polydopamine nanoparticles modified by 4-mercaptophenylboronic acid for use in a glucose sensor

Au nanoparticles were attached to the surface of polydopamine (PDA) macrospheres by an in situ reduction reaction between PDA and HAuCl4. 4-Mercaptophenyl boronic acid (MPBA) was then modified to form Au–PDA composite particles via a strong Au–S interaction. The resultant MPBA–Au–PDA particles were used in a non-enzyme amperometric glucose sensor.

Boronic acid functionalized N-doped carbon quantum dots as fluorescent probe for selective and sensitive glucose determination

Nitrogen doped carbon quantum dots (NCQDs) of about 10 nm in diameter have been obtained by hydrothermal reaction from collagen. Because of the superiority of water dispersion, low toxicity and ease of functionlization, the NCQDs were designed as a glucose sensor after covalent grafting by 3-aminophenylboronic (APBA) (APBA-NCQDs). The as-prepared APBA-NCQDs were imparted with glucose sensitivity and selectivity from other saccharides via fluorescence (FL) quenching effect at physiological pH and at room temperature, which show high sensitivity and specificity for glucose determination with a wide range from 1 mM to 14 mM. FL quenching mechanism of APBA-NCQDs was also investigated by adding an external quencher. The APBA-NCQDs-based platform is an environmentally friendly way to substitute inorganic quantum dots containing heavy metals which offer a facile and low cost detection method.

Preparation of N-Doped Bi2WO6 Microspheres for Efficient Visible Light-Induced Photocatalysis

The N-doped bismuth tungstate (Bi2WO6) photocatalysts with high visible light activity were prepared by the hydrothermal method using urea as a nitrogen source. The as-prepared N-doped Bi2WO6 samples were characterized by X-ray diffraction, scanning electron microscopy, specific surface area, photocurrent analysis, and UV–Vis diffuse reflectrance spectroscopy. The photocatalytic activity was evaluated by photocatalytic degradation of rhodamine B (RhB) solution under visible light irradiation. The photocatalytic mechanisms were analyzed by active species trapping experiments which revealed that the holes were the main active species of N-doped Bi2WO6 products in aqueous solution under visible light irradiation, rather than ·OH and O2•−. With the assistance of H2O2, the photocatalytic activity for degradation of RhB could be further improved because H2O2 reacted with conduction band electrons to generate more hydroxyl radicals.

Preparation of Au/PAN nanofibrous membranes for catalytic reduction of 4-nitrophenol

Due to their high surface energy, naked gold nanoparticles (AuNPs) tend to form agglomerates, which could lead to the decrease of active sites and catalytic activity of AuNPs. Herein, the gold nanoparticles/polyacrylonitrile (AuNPs/PAN) nanofibrous membranes have been prepared via an environmentally friendly and efficient route combining electrospinning, amination, and electroless plating technique. The abundant amine and imine groups can be introduced onto the surface of PAN nanofibrous membranes via amination treatment which could be used as “anchoring sites” to immobilize AuNPs. The resultant composite membranes were applied as the new catalytic materials for reduction of 4-nitrophenol to 4-aminophenol under room temperature. The new catalytic membranes exhibited the significant advantages, such as low dosage, high catalytic activity, easy recycling, and excellent stability.

Facile one-pot synthesis of fluorescent hyperbranched polymers for optical detection of glucose

Fluorescent and glucose-sensitive hyperbranched poly(amidoamine)s (HPAMAMs-B) were synthesized via Michael addition of 1-(2-aminoethyl) piperazine, methyl acrylate, and 3-aminobenzeneboronic acid (APBA). These hyperbranched polymers emitted chartreuse photoluminescence and showed emission band at 378 nm under excitation wavelength. The intensity of emission band was enhanced with increasing the amount of APBA in HPAMAMs-B. The glucose sensitivity of HPAMAMs-B has been investigated at different glucose concentrations and pH conditions. These hyperbranched polymers showed potential for biomedical applications such as fluorescence imaging technology and glucose detecting sensors.

Facile fabrication of highly flexible graphene paper for photocatalytic reduction of 4-nitrophenol

Freestanding paper-like materials prepared from chemically derived graphene have considerable potential as a carbon-based catalyst in high-performance flexible catalytic reaction. Herein, a highly flexible graphene paper (GP) assembled from graphene oxides (GOs) with the aid of polyacrylamide (PAA) and electroless deposition of gold nanoparticles (AuNPs) was prepared. In contrast to previous reports on GOs based on a flow-directed assembly of graphene sheets, this GOs/PAA/Au composite paper exhibited a highly wrinkled and disordered morphology. The resultant GOs/PAA/Au composite paper was applied as a catalytic material for the reduction of 4-nitrophenol and showed the favour separation, recovery and cyclic utilization properties.

Effects of N and/or S Doping on Structure and Photocatalytic Properties of BiOBr Crystals

The BiOBr crystals doped with N and/or S have been prepared by a facile and rapid solvothermal method using urea and/or thiourea as doped resource. The morphologies and structures of the as-prepared samples were characterized by SEM, TEM, XRD, XPS and PL spectrum. Their electronic structures have been investigated and discussed using first principles based on the density functional theory. The photocatalytic properties of the products can be adjusted by the content and species of dopants.

N-Doped carbon hybrid conjugates as vectors for photocatalytic CS2 production

Nanostructured carbon materials have attracted much attention, because the doping or modification can efficiently induce charge delocalization and tune the work function of carbon. Herein, we report that N-doped carbon hybrid conjugates are highly sensitive in photocatalytic CS2 production due to the energy transfer and electron transfer between carbon and organic ligands. The key towards success was opening a new avenue for the cheap and rapid release of a potential therapeutic agent using carbon materials as vectors.