Feng Zhang's research while affiliated with Tongji University and other places

In this article, cupric oxide (CuO) leafletlike nanosheets have been synthesized by a facile, low-cost, and surfactant-free method, and they have further been successfully developed for sensitive and selective determination of hydrogen sulfide (H2S) with high recovery ability. The experimental results have revealed that the sensitivity and recovery time of the present H2S gas sensor are strongly dependent on the working temperature. The best H2S sensing performance has been achieved with a low detection limit of 2 ppb and broad linear range from 30 ppb to 1.2 ppm. The gas sensor is reversible, with a quick response time of 4 s and a short recovery time of 9 s. In addition, negligible responses can be observed exposed to 100-fold concentrations of other gases which may exist in the atmosphere such as nitrogen (N2), oxygen (O2), nitric oxide (NO), cabon monoxide (CO), nitrogen dioxide (NO2), hydrogen (H2), and so on, indicating relatively high selectivity of the present H2S sensor. The H2S sensor based on the CuO nanosheets also shows strong recovery ability and long-term stability, probably due to the effective diffusion of gas toward the whole sensing surface, as well as the different mechanism of H2S gas sensor from those reported at CuO nanowires and CuO−SnO2 nanocomposites, where a layer of CuS or Cu2S has formed on the CuO surface.

A Pt-NiCo nanomaterial has been synthesized for developing the sensitive electrochemical determination of biological thiols that include L-cysteine (CySH), homocysteine (HCySH), and gluthione (GSH) with high sensitivity and long-term stability, in which the Pt nanoparticles are well supported on amorphous NiCo nanofilms. The electrochemical oxidation of thiols has been successfully facilitated on the optimized Pt-NiCo nanostructures, that is, two oxidation peaks of CySH have been clearly observed at potentials of +0.06 and +0.45 V. The experimental results demonstrate that the first peak for CySH oxidation may be attributed to a direct oxidation from CySH to L-cystine (CySSCy), whereas the second peak possibly results from a sequential oxidation from CySSCy to cysteic acid (CySO(3)H), together with a direct oxidation of CySH into CySO(3)H. The enhanced electrocatalytic activities at the Pt(23)-NiCo nanostructures have provided a methodology to determine thiols at a very low potential of 0.0 V with relatively high sensitivity (637 nA μM cm(-2)), a low detection limit (20 nM), and a broad linear range. The striking analytical performance, together with the characteristic properties of the Pt-NiCo nanomaterial itself, including long-term stability and strong antipoisoning ability, has established a reliable and durable approach for the detection of thiols in liver cancer cells, Hep G2.

Amorphous ternary FeNiPt nanomaterials with tunable length are reported for constructing the electrochemical sensing platform, in which hydrogen peroxide (H2O2) is selected as a model target. It is found that amorphous FeNiPtnanostructures, in particular, the FeNiPtnanorods with large axial-ratio (FeNiPt-NRL) exhibit the enhanced electrocatalytic activity towards both the oxidation and reduction of H2O2. Meanwhile, the comparable corrosion potential Ecorr and lower corrosion current Icorr are observed at GCelectrodes modified with FeNiPt-NRL, revealing the good stability of the FeNiPt-NRL surface. On the basis of these results, H2O2 is cathodically determined at glassy carbon (GC) electrodes with FeNiPt-NRL with relatively high selectivity at the appropriate potential of 0 V vs. Ag|AgCl. On the other hand, the sensitivity of the anodic H2O2 detection at the same electrode is achieved to be 2.45 mA cm−2 mM−1, which is 4-fold larger than that of the cathodic detection and those Ptnanoparticles-based H2O2 determination, and the detection limit is also developed to 40 nM. The dynamic linear range is broadened from 100 nM to 30 mM, which is wider than those H2O2 detection based on Ptnanoparticles and binary Pt alloys. In addition, electrochemical results show the high stability and good reproducibility for the present H2O2 sensor. The striking analytical performance combined with the intrinsic properties of amorphous FeNiPt nanomaterials provides a promising technique for the development of non-enzyme H2O2 and other molecule sensors with high sensitivity, broad dynamic linear range, long stability, and good reproducibility.

Amorphous FeNiPt nanoparticles with tunable length have for the first time been reported to exhibit excellent electrocatalytic performance in the electrochemical determination of thiols.