Jianhua Zhou

Bio: Jianhua Zhou is an academic researcher from Qilu University of Technology. The author has contributed to research in topics: Detonation & Self-healing hydrogels. The author has an hindex of 5, co-authored 17 publications receiving 69 citations.

Two Novel Fluorescent Probes as Systematic Sensors for Multiple Metal Ions: Focus on Detection of Hg2.

Abstract: Many precedents prove that fluorescent probes are promising candidates for detection of metal ions in the environment and biological systems. Herein, two novel photoinduced electron transfer (PET)-...

Two novel colorimetric fluorescent probes: Hg2+ and Al3+ in the visual colorimetric recognition environment

Abstract: Two new dual channel Schiff base fluorescent probes, Tri-R6G and Tri-Flu, were synthesized, and can detect Hg2+ and Al3+, respectively. The two probes were characterized by FTIR, 1H NMR, 13C NMR and HRMS, and their optical properties were detected by UV and FL. Test results showed the probes' detection of Hg2+ and Al3+ compared to other metal ions (Ag+, Co2+, Cd2+, Mg2+, Cu2+, Ni2+, Ba2+, Pb2+, Cr3+, Al3+, Zn2+, Hg2+, K+, Ga2+ and Fe3+), respectively. Besides, the detection limits were determined to be 1.61 × 10−8 M and 1.15 × 10−8 M through the standard curve plot, respectively. The photoelectron transfer (PET) mechanism was guessed by the Job's plot and the infrared titration. Corresponding orbital electron distribution and molecular geometry configurations of the compounds were predicted by density functional theory (DFT). In addition, the prepared test paper changed from white to pink when the target ion was detected. The color changed from colorless to pink in a solution having a concentration of 10−5 M.

Atomic thermodynamics and microkinetics of the reduction mechanism of electrolyte additives to facilitate the formation of solid electrolyte interphases in lithium-ion batteries

Abstract: The formation of a solid electrolyte interphase (SEI) between the anode surface and the electrolyte of lithium-ion batteries (LIBs) has been considered to be the most important yet the least understood issue of LIBs. To further our understanding in this regard, the density functional theory (DFT) B3PW91/6-311++G(3df,3pd) together with the implicit solvent model and the transition state theory were used for the first time to comprehensively explore the electroreduction mechanism of a novel additive, 4-chloromethyl-1,3,2-dioxathiolane-2-oxide (CMDO), and a few other solvents and additives, such as ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), fluoroethylene carbonate (FEC), and even ethylene sulfite (ES), for comparison. The one-electron reduction potential of Li+-coordinated compounds Li+(X) for forming decomposition precursors [c-Li+(X˙−)] decreases in the following sequence: CMDO (1.9–2.2 V vs. Li+/Li) ∼ ES(1.9 V) > FEC (0.7 V) > EC (0.47 V) > PC (0.45 V) > DMC (0.38 V); this implies that CMDO is reduced prior to other solvents or additives in the mixture. Although the ring opening of [c-Li+(CMDO˙−)] is the least kinetically favorable, as reflected by the highest energy barrier (Ea), i.e., CMDO (18.8–22.9 kcal mol−1) ∼ ES (23.4) > FEC (16.2) > PC (12.5) > EC (11.2) > DMC (8.0), CMDO still shows the highest overall reaction rate constant (∼1053 s−1) for forming an open ring radical [o-Li+(CMDO˙)−]. In addition, the termination reaction of [o-Li+(CMDO˙)−] for forming LiCl is thermodynamically more favorable than that of Li2SO3 or organic disulfite (LiSO3)2-R, which supports the experimental observation that the halogen-containing LiF or LiCl additives are predominant over all other halogen-containing species in the SEI layer. Moreover, the hybrid model by including the second solvation shell of Li+ via a supercluster [(CMDO)Li+(PC)2](PC)9 and the implicit solvent model (SMD) can result in a reduction potential (∼1.7 V) that is in excellent agreement with the experimental reduction peak.

Molecule design and properties of bridged 2,2-bi(1,3,4-oxadiazole) energetic derivatives

Abstract: A series of bridged 2,2-bi(1,3,4-oxadiazole) energetic derivatives were designed and their geometrical structures, electronic structures, heats of formation, detonation properties, thermal stabilities and thermodynamic properties were fully investigated by density functional theory. The results showed that the –N3 group and the –N– bridge play an important role in improving heats of formation of these 2,2-bi(1,3,4-oxadiazole) derivatives. The calculated detonation properties indicated that the –NF2 group and the –N– bridge were very useful for enhancing the heats of detonation, detonation velocities and detonation pressures. Twenty-four compounds were found to possess equal or higher detonation properties than those of RDX, while 14 compounds had equal or higher detonation properties than those of HMX. The analysis of the bond-dissociation energies suggested that the –CN group was the effective structural unit for increasing the thermal stabilities while the –NHNH2 group decreased these values. Overall, taking both the detonation properties and thermal stabilities into consideration, 22 compounds (A4, A6, A8, A9, B4, B9, C2, C3, C4, C5, C7, C, C9 D4, D8, D9, E9, F4, F9, G9, H4 and H9) were selected as the potential candidates for high-energy-density materials.

Molecular design and selection of 1,2,5-oxadiazole derivatives as high-energy-density materials

Abstract: In the present study, 64 energetic compounds based on 1,2,5-oxadiazole were designed and their energy gaps, heats of formation (HoF), detonation properties, and thermal stabilities were fully investigated by density functional theory at the B3LYP/6-311G(d,p) level. All the designed compounds possessed high positive ΔHf,gas values and the –NH– bridge and –N3 group were the most effective ones for improving the HoFs of these compounds. The predicted densities and detonation properties showed that –C(NO2)3 and –O– were the most effective groups to improve the densities, while –C(NO2)3 and –NH– were the most effective groups to improve the detonation velocities. When the compounds were substituted by –NHNH2/–NHNO2/–C(NO2)3/–CH(NO2)2 groups, the BDE values of the NH–NH2/NH–NO2/C–(NO2)3/CH–(NO2)2 bonds were the lowest, which indicated that the NH–NH2/NH–NO2/C–(NO2)3/CH–(NO2)2 bond cleavages were the possible thermal decomposition path for these compounds. In addition, incorporating the –NHNH– bridge into the compounds decreased the BDE values. Overall, the effects of the substituents on these properties were combined with those of the bridge groups. Taking the detonation properties and thermal stabilities into consideration, eight compounds (A3, C2, C3, C6, D3, G3, H3, and H5) were selected as high-energy-density compounds and their electronic structures were investigated to gain a better understanding of these compounds.

Theoretical Study on CL-20-Based Cocrystal Energetic Compounds in an External Electric Field.

Abstract: An external electric field has great effects on the sensitivity of cocrystal energetic materials. In order to find out the relationship between the external electric field and sensitivity of cocrys...

A hydrogel microsphere-based sensor for dual and highly selective detection of Al3+ and Hg2+

Abstract: Traditional fluorescent sensors for simultaneous detection of metal ions require the use of specially designed fluorescent probes In this manuscript, we have employed a new strategy for the design of a sensor for simultaneous detection of metal ions that is based on a fluorescent probe encapsulated hydrogel matrix An investigation designed to assess this strategy led to the development of a novel dual fluorescent encapsulated hydrogel microsphere sensor for sensitive and simultaneous detection of Al3+ and Hg2+ The hyperbranched poly (poly (ethylene glycol) diacrylate) (HB-PEGDA) and thiolated sodium alginate (SA-SH) composite hydrogel microspheres used to construct the sensor, which contain two fluorescent probes encapsulated in a highly dense manner, were prepared by using a self-assembly method in conjunction with a microfluidic device The functionalized hydrogel microspheres were shown to exhibit high selectivity for Al3+ and Hg2+ among various metal ions with a detection limit of 70 nM and 120 nM, respectively In addition, the hydrogel microspheres can be readily separated from test samples and utilized for repeated use by removing Al3+ and Hg2+ by addition of a solution containing EDTA and KI Compared with previously devised sensors, the new HB-PEGDA/SA-SH composite hydrogel microspheres containing two encapsulated fluorescent probes are readily prepared and effective for simultaneous detection of two different metal ions

A Highly Selective Fluorescent Probe for Hg2+ Based on a 1,8-Naphthalimide Derivative.

Abstract: Hg2+ has a significant hazardous impact on the environment and ecosystem. There is a great demand for new methods with high selectivity and sensitivity to determine mercury in life systems and environments. In this paper, a novel turn-on Hg2+ fluorescent probe has been reported with a naphthalimide group. The Hg2+ fluorescent probe was designed by the inspiration of the well-known specific Hg2+-triggered thioacetal deprotection reaction. A 1,2-dithioalkyl group was chosen as the specific recognition site of Hg2+. The probe showed weak fluorescence without Hg2+, and the color of the solution was light yellow. In the presence of Hg2+, the probe reacted specifically with the mercury ion to produce an aldehyde and emitted strong fluorescence, and the color of the solution also turned light green, thus realizing the monitoring of the mercury ion. The Hg2+ fluorescent probe showed outstanding sensitivity and selectivity toward Hg2+. Furthermore, the Hg2+ fluorescent probe could work in a wide pH range. The linear relationship between the fluorescence intensity at 510 nm and the concentration of Hg2+ was obtained in a range of Hg2+ concentration from 2.5 × 10-7 to 1.0 × 10-5 M. The detection limit was found to be 4.0 × 10-8 M for Hg2+. Furthermore, with little cell toxicity, the probe was successfully applied to the confocal image of Hg2+ in PC-12 cells.