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An electrochemical biosensor was developed based on a steric hindrance hybridization assay to allow the highly sensitive detection of streptavidin. In the steric hindrance hybridization assay, the signaling strand DNA (sig-DNA) was labeled at the 3' end with CdSe quantum dots (QDs) and at the 5' end with biotin, and capturing strand DNA (the complementary strand of sig-DNA) was labeled at the 5' end with thiol. The steric hindrance effect generated by streptavidin which was bound with the signaling DNA strand. The streptavidin limited the ability of the sig-DNA to hybridize with the cap-DNA, which were linked on the surface of a gold electrode. Therefore, the concentration of streptavidin was detected indirectly based on the concentration of CdSe QDs on the electrode surface. The concentration of CdSe QDs on the electrode surface was detected by differential pulse anodic stripping voltammetry. Under optimal conditions, the streptavidin detection range using the as-prepared biosensor was 1.96pg/mL to 1.96µg/mL and the detection limit was 0.65pg/mL. The experimental results showed that the electrochemical biosensor could detect streptavidin rapidly and accurately.

A novel sensor was assembled by combining CdTe quantum dots (QDs) with nitrogen-doped graphene (NG) on the surface of glassy carbon electrode. The sensor as-assembled with the NG/CdTe QDs composite exhibited high electrochemiluminescence (ECL) intensity and long-time ECL stability. The ECL mechanism and effect factors on ECL emission of the sensor are discussed. Significantly, the sensor was used in ascorbic acid (AA) detection based on the ECL quenching of AA. The results show that the sensor has a linear response range from 0.04 to 200 μM and the detection limit of 0.015 μM for AA.

Electron transfers (ET) of 5–hydroxy–1, 4–naphthoquinone (HNQ) and 5–hydroxy–2–methyl–1, 4–naphthoquinone (HMeNQ) have been investigated in acetonitrile and proton donors mixed media. Although there is merely a small difference in structure between HMeNQ, having a methyl, and HNQ, not having a methyl, the reduction of HNQ involves proton coupled electron transfers (PCET) process while HMeNQ not. Both CV and rapid–scan IR spectra support the existence of intermediate HNQ− and dimer in acetonitrile during electrochemical reduction. Density functional calculations show that proton transfers (PT) occur when forming dimer, indicating that HNQ has PCET–accompanied dimerization mechanism. Besides, dimer also undergoes two successive ET processes to form quinone. When proton donors are added to HNQ, dimerization is inhibited owing to intermolecular hydrogen–bonding, accompanying by the interruption of PCET process.

The electrochemical capture of carbon dioxide in p-Benzoquinone (BQ) - acetonitrile and BQ - aqueous solutions have been investigated by cyclic voltammetry (CV). Two well-defined couples of anodic and cathodic peaks in CV curve of BQ in acetonitrile solvent are substituted by one redox couple peaks with E1/2 = −0.30 V once CO2 is added. The absorption peak at 2348 cm−1 of in situ FT-IR spectroelectrochemistry indicates that CO2 is involved in the electrochemical reactions. Cyclic voltabsorptometry (CVA) and derivative cyclic voltabsorptometry (DCVA) of BQ - acetonitrile with different concentration of CO2 are investigated to demonstrate the reaction stoichiometry. The absorbance value of BQ at 2348 cm−1 is a constant during reduction process when CO2 concentration is lower than 50%. However, there is a decrease at −1.3 V potential due to the CO2 reduction when it is higher than 50%. This indicates the stoichiometry of BQ•− to CO2 is 1:1 during electrochemical capture of CO2 in CH3CN solution. Similar reaction between CO2 and BQ is observed in aqueous solution. However, the stoichiometric number of BQ•− to CO2 is 1:2, forming [BQ-2CO2]•−, which is finally reduced to [BQ-2CO2]2-. The mechanism proposed is consistent with theoretical calculation since the activation energy of [BQ-CO2]•− formation is much lower than that of BQ•− reduction. The stable structures of CO2 adduct of the reactions in aprotic and aqueous solvents are also proposed according to density functional theoretical (DFT) calculations.

In this study, a typical intramolecular charge transfer (ICT) triphenylamine derivative, [4-(diphenylamino)phenyl]methylenepropanedinitrile (abbreviated as DPMP) was synthesized. Controllable one dimensional (1D) nanocrystals of DPMP have been obtained through reprecipitation method. The thermodynamic relationship of the molecular structure and growth process in nanometer scale of DPMP was investigated through density functional theory (DFT) calculation, which was performed on the weak interactions between adjacent molecules. The results showed that the assembling interactions along a axis were much stronger than that along b and c axis, which meant that 1D orientation growth along a axis would be the most stable state in thermodynamics, that is to say, DPMP molecules tended to form 1D orientation structure. The study is helpful to understand the relationship of molecular structure, weak interactions, orientation growth process and self-assembling morphology.

The synthesis of polyaniline/platinum microelectrodes (PPME) have been achieved for the first time by using the controlled electrochemical reduction of PtCl 6 2− . First, the PANI film was electrochemical prepared on the glass carbon electrode (GCE) surface by using the method of CV. It was found that the PANI film is composed of 100–200 nm diameter rods. Then, the electrochemical reduction of PtCl 6 2− on the PANI modified surface was carried out and Pt particle was about 300–600 nm in diameter on the end of PANI membranes. Electrochemical experiments show that the microelectrodes have superior catalytic performance toward formaldehyde and methanol electrochemical oxidation.

The stability and electronic structures of the new sandwich compounds M(CrB6H6)2 (M = Cr, Mn+, Fe2+) are investigated by density functional theory. All the investigated sandwich complexes are in D6d symmetry and all of them are thermodynamically stable according to the large HOMO–LUMO gap, binding energy, vertical ionization potential and vertical electron affinity analyses, as well as Fe(C5H5)2 and Cr(C6H6)2, following the 18-electron principle. The natural bond orbital, detailed molecular orbitals and adaptive natural density partitioning analyses suggest that the spd–π interaction plays an important role in the sandwich compounds. This work challenges the traditional chemical bonding of the inorganic metal compound, investigates first the bonding style of the d atom orbital interacting with the π MO which was formed by p–d atomic orbitals, and indicates that the metal-doped borane ring can also be an ideal type π-electron donor ligand to stabilize the transition metal.

A facile chemical method has been developed for the synthesis of the Cu 2 Te nanorods with hexagonal crystalline phase. The method is based on the template-engaged synthesis in which the Te nanorods were used as self-sacrificial template. On the basis of a series of experiments and characterizations, the effect factors and the formation mechanism of the Cu 2 Te nanorods were discussed. Furthermore, the electrochemical property of the Cu 2 Te nanorods was investigated by the voltammetric technique.

A novel graphene oxide nanosheets/polyaniline nanowires/CdSe quantum dots (GO/PANi/CdSe) nanocomposites are successfully synthesized and use as ECL immunosensor for detection of human interleukin-6 (IL-6). The as-prepared GO/PANi/CdSe nanocomposites show excellent biocompatibility, dispersity and solubility. Electrochemiluminescence (ECL) of CdSe quantudm dots (QDs) was greatly enhanced by combining with GO/PANi nanocomposites. Herein, this GO/PANi/CdSe nanocomposite was applied to develop an ultrasensitive ECL immunosensor for detection of IL-6. The ECL immunosensor has a sensitive response to IL-6 in a linear range of 0.0005–10 ng mL −1 . The prepared ECL immunosensor exhibits high specificity, long-term stability and excellent reproducibility with a detection limit of 0.17 pg mL −1 .

As a novel supercapacitor material, nickel sulfide/graphene oxide (NiS/GO) nanocomposite was synthesized by a hydrothermal process in the presence of graphene oxide. For the NiS/GO nanocomposite as-obtained, the characterization results show that the NiS particles (50 nm) distribute evenly on the GO sheets. The electrochemical property and impedance of the NiS/GO nanocomposite were studied by cyclic voltammetry and electron impedance spectroscopy analysis, respectively. The results show that the introduction of the GO enhanced the electrode conductivity, and then improved the supercapacitive behavior of the NiS/GO nanocomposite. The galvanostatic charge/discharge measurement results indicate that the NiS/GO nanocomposite has a high specific capacitance (800 F g −1 at 1 A g −1 ) and long cycle life (over 1000 cycles).

A rapid chemical method has been developed for the synthesis of the Sb 2 Te 3 nanoplates with rhombohedral crystalline phase. The method is based on the template-engaged synthesis in which the Te nanorods were used as template reagents. On the basis of a series of experiments and characterizations, the effect factors and the formation mechanism of the Sb 2 Te 3 nanoplates were discussed. Furthermore, the electrochemical property of the Sb 2 Te 3 nanoplates was determined by the voltammetric technique.

A novel amplification system for electrochemiluminescence (ECL) was developed by combining graphene oxide (GO) and Se nanoparticles, in which the chitosan (CHIT) was used as improver. Based on a series of experiments, the influencing factors and mechanism for ECL emission were determined. Under optimal conditions, the GO/Se nanocomposite produced an intense ECL emission and maintained long-term ECL stability. Significantly, the electrode modified with GO/Se nanocomposite was used to detect the biomolecule dopamine (DA), and showed a linear range from 0.1 to 100 µM, with a detection limit of 0.025 µM.

By dipping-lifting in sol–gel solution and reducing process, the TiO2 composite film on the glass plate was first prepared. Then, the PbSe/BaTiO3/TiO2 composite film was fabricated by interface reaction with BaTiO3 and PbSe on the surface of TiO2 composite film. The characterization results show that the uniform porous TiO2 film is made up of the anatase crystal, and the PbSe/BaTiO3/TiO2 composite film is constructed by doping or depositing BaTiO3 and PbSe nanoparticles on the surface of TiO2 film. The photoelectrochemical measurement results indicate that the PbSe/BaTiO3/TiO2 composite film has an interesting photoelectrochemical conversion property.

The electrochemical reduction of 1,8-dihydroxy-9,10-anthracenedione (Q) has been investigated by cyclic voltammetry (CV). Both 9,10-anthroquinone (AQ) and 1,8-methoxy-9,10-anthracenedione (DMeAQ) are reduced in two steps. First, they are reduced to the anion radical. Next, the anion radicals are reduced to the dianion. However, the CV of Q shows more cathodic and anodic peaks, which suggests the formation of a neutral- anion radical complex. To study the reaction mechanism of Q, in situ infrared (IR) spectroelectrochemistry, IR cyclic voltabsorptometry (CVA), and derivative cyclic voltabsorptometry (DCVA) spectroelectrochemical techniques are used to track the electrochemical reduction process. It is found that Q is reduced to Q•–, then Q•– reacts with Q to produce dimer Q2•–. What’s more, both the π-dimer and σ-dimer can be observed during the electrochemical process by an IR spectroelectrochemical technique. As a result, a new reaction mechanism of Q has been proposed by this powerful approach.

The electrochemical character of p-aminophenol in non-aqueous media was investigated by cyclic voltammetry (CV). Two couples of redox peaks and two shoulder peaks are observed in cyclic voltammogram. By in situ FT-IR spectroelectrochemistry, several IR absorption peaks, 1518, 1256, 1210; 1610, 1503, 1272; 1664, 1649, 1595, 1287 cm−1, corresponding to OHC6H4NH2; (OHC6H4NH2)+ and dimer; (OHC6H4NH2)2+ and C6H4ONH, are observed. Based on cyclic voltabsorptometry (CVA) and derivative cyclic voltabsorptometry (DCVA) techniques, we can track the changes of each species during electrochemical process. The results indicate that p-AP is oxidized in two-step one-electron transfer, and moreover, amino group is first oxidized than the hydroxyl group. The final oxidized product is quinonimine, and meanwhile the formation of dimer is detected. The dimer can be oxidized at more positive potential to form the final oxidation product (quinonimine) and reduced at more negative potential to form a new reduction product. By calculating relative energy, three possible structures of the dimer are proposed.

以KNO 3 为矿化剂, 用水热法制备了3D分级结构Bi 2 WO 6 微球, 通过XRD、SEM、BET对产物进行了表征. 探讨了3D分级结构Bi 2 WO 6 微球可能的形成机理. 以罗丹明B为模型污染物, 研究了合成产物的光催化性质. 结果表明: 在紫外光下, RhB的降解以共轭结构断裂的光催化反应为主; 而在可见光照射下, RhB的降解可能是光催化和光敏化共同作用的结果. 进一步以吡啶为探针分子, 通过吸附吡啶红外光谱探讨了Bi 2 WO 6 表面酸性与光催化降解RhB之间的关系. 研究显示, Bi 2 WO 6 具有较强的表面酸性, 增强了Bi 2 WO 6 与RhB分子之间吸附作用, 有利于染料分子上的电子跃迁至催化剂上, 易于发生光敏化和光催化反应.

A novel graphene oxide nanoribbon/poly(diallyldimethylammonium chloride)/gold nanoparticle (GONR/PDDA/AuNP) nanocomposite was synthesized successfully and used for the sensitive detection of dopamine. The GONR/PDDA/AuNP nanocomposite was characterized by transmission and scanning electron microscopy. The electrochemical sensor based on GONR/PDDA/AuNP nanocomposite. was studied by cyclic voltammetry and electrochemical impedance spectroscopy. Experimental parameters such as GONR/PDDA concentration, volume ratio of GONR/PDDA to AuNP, scan rates, and pH were studied to investigate their effect on peak currents. Under optimal conditions, the GONR/PDDA/AuNP-based sensor exhibited excellent electrocatalytic activity for the detection of dopamine with a wide linear range from 9.99 x 10(-8) to 8.69 x 10(-4) M and a low detection limit of 3.33 x 10(-8) M. Moreover, the proposed sensor exhibits high sensitivity, good reproducibility, and stability, and could therefore potentially be applied in other bioanalytical systems.

A novel donor–acceptor–donor (D–A–D) biferrocenyl derivative, 2-amino-4,6-diferrocenylpyrimidine, has been synthetized and characterized by 1 H NMR, elemental analysis, IR and UV absorption spectroscopy, thermogravimetric analysis (TGA) and X-ray crystallography. The crystal structure revealed that the molecular configuration displayed a good coplanarity. The obtained cis-isomer showed a different arrangement due to the induced metal ion Cd(II). The electronic spectrum features were explained by density functional theory (DFT) which agreed well with the experimental data. The cyclic voltammetry (CV) showed the half wave potential of the compound was more positive than that of the standard ferrocene (Fc), indicating that the strong electron-withdrawing effect of the aminopyrimidine moiety made the ferrocene units more difficult to oxidize. Especially, the nonlinear optical (NLO) properties were determined by optical limiting and Z-scan techniques, which suggested a strong π-electron delocalization and a large polarizability in the molecule reasonably equipped for meeting the requirements for third-order NLO materials.

A novel coupled system of ZnWO4–Cu, combining two different advanced oxidation processes of photocatalysis and Fenton-like for the degradation of organic dyes, was successfully synthesized. The as-synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS). The nanosized ZnWO4–Cu samples exhibited much higher catalytic activity than pure ZnWO4. In the presence of the ZC-0.2, the MB solution was completely degraded (the degradation ratio reached 97.79%); while for the ZC-0, the degradation ratio was only 72.29%. The effects of the amount of Cu on the photocatalytic performance of ZnWO4–Cu were investigated in detail. The result showed that the synergistic effect between Cu and ZnWO4 played a key role. The possible mechanism of the synergistic system was proposed.

Two novel biferrocenylcarboxylate benzene derivatives, namely, 1,4-bis(2-Ferrocenecarboxylate) benzene (Fc2B) and 1,4-bis(2-Ferrocenecarboxylate)-2′-methylbenzene (Fc2M), have been synthesized. The as-prepared complexes have been confirmed by IR, 1H NMR and MS. The electron transfer mechanisms of the two compounds and the other three bisferrocenyl bridged benzene complexes, 1,4-disferrocenyl benzene (Fc2P), 1,4-bis(2-ferrocenylvinyl) benzene (Fc2E), and 1,4-bis(2-ferrocenylacetyleneyl) benzene (Fc2Q), have been studied by cyclic voltammetry (CV), in situ difference FT-IR (SNFTIR), and rapid-scan time-resolved FT-IR spectroelectrochemistry (RS-TRS FT-IR). The CV results suggest that the redox formal potentials of the five bridged complexes are depended on their bridged groups and abilities of withdrawing electron. IR absorption peaks arisen from intermediate appearance and disappearance in the oxidation and reduction process of Fc2B, Fc2E, Fc2P and Fc2Q were clearly observed by the in situ rapid-scan or SNFTIR spectroelectrochemistry. The results indicated the redox process of the four bisferrocenyl bridged benzene complexes involved two consecutive one-electron steps. Although the intermediate peak of Fc2M was not observed by in situ FT-IR spectroelectrochemistry, we still thought the redox process of Fc2M could involve two consecutive one-electron steps.

A novel cuprous(I) cluster Cu4I4L4 (L = (E)-(4-diethylanilino-styryl)pyridine) bearing strong two-photon absorption (TPA) was obtained using a facile assembly method, and the crystal structure has been determined. Quantum chemical calculations using time-dependent density functional theory (TD-DFT) reveals that the combination of the organic ligands with the three-dimensional Cu4I4 core extends the electronic delocalization in the cluster, leading to strong two-photon absorption action. The TPA cross sections (Φσ2) of Cu4I4L4 were enhanced with increasing polarity of solvents, which is quite different from the solvent effects on TPA in the literature. Compared to its free ligand, the cluster Cu4I4L4 exhibits larger peak TPA cross sections in the near-infrared region, longer fluorescence lifetimes, higher quantum yield and photostability, lower cytotoxicity, and brighter two-photon fluorescent (TPF) bioimaging. These integrated advantages make it desirable to be applied as a two-photon fluorescent probe fo...

The electrochemical behavior of 1,4-dinitrobenzene (1,4-PNB) on the Au electrode was investigated by cyclic voltammetry (CV), in situ FT-IR spectroelectrochemistry, cyclic voltabsorptometry (CVA) and derivative cyclic voltabsorptometry (DCVA) techniques. In aprotic media, 1,4-dinitrobenzene is reversibly reduced in two-step one-electron transfer. A series of IR absorption bands at 1056, 1210, 1341, 1356, 1464 and 1549 cm−1, tracing to PNB; PNB − and PNB2− are observed. In the presence of proton donors mixed media, with increasing concentrations of proton donors, hydrogen-bonding and protonation process are found successively. The values of combining proton donors with per PNB2− to form hydrogen-bonding are estimated by using electrochemical parameters. The result of forming aromatic nitroso compound is supported by tracing the change of IR absorption bands at 1149 and 1587 cm−1 at high concentration of proton donors. Based on CVA and DCVA techniques, it is clearly distinguished that the mechanisms of electrochemical reduction of PNB are elaborated in different systems.

A novel ferrocene-containing ligand 3-trifluoromethyl-5-ferrocenyl -pyrazol-1-yl-acetic acid ( LCOOH ) and three organotin(IV) carboxylate derivatives [Ph 4 Sn 2 O(OCH 3 )(OOCL)] 2 (1) , [BuSnO(OOCL)] 6 (2) and [Bu 4 Sn 2 O(OOCL 2 ) 2 ] (3) have been synthesized and structurally characterized by means of FT-IR, elemental analysis, 1 H NMR, 119 Sn NMR, X-ray crystallography and cyclic voltammetry. Both complexes 1 and 3 are centrosymmetric with ladder framework. Complex 2 is a hexanuclear one with drum structure. Furthermore, their anti-tumor activities were also evaluated, using HepG2 human hepatocellular liver carcinoma cells, A549 human lung carcinoma cells and B16-F10 melanoma cells. Complex 1 displayed the best cytotoxicity and can be pointed out as a promising substrate to be subject of further investigations.

Electrochemically reduced graphene oxide modified glassy carbon electrodes (ERGC) were obtained under various reducing conditions to control the content of oxygen-functional groups (OxFG). By utilizing Fe ( CN ) 6 3 - / Fe ( CN ) 6 4 - , AA and DA as redox probes cyclic voltammogram (CV) and differential pulse voltammogram (DPV) results indicated that for various substances the effect of OxFG was distinct and different types of OxFG (C O, C O C, OH, COOH, etc.) played entirely different roles for one substance which were reflected in peak potential shift and peak current change. Finally, the optimum reducing conditions of fabricating ERGC for the detection of AA and DA separately and simultaneously were explored and satisfactory results were obtained.

CeO2/TiO2 composite with kernel–shell structure was synthesized by a sol–gel process. The characterization results show that the composite is made up of anatase phase TiO2 and cubic system CeO2. The electrochemiluminescence (ECL) behavior of the CeO2/TiO2 composite was studied by a cyclic voltammetry in the presence of persulfate, and the effect factors on ECL emission were discussed. Based on a series of experiments, it is proposed that the strong dual ECL emission produced by the CeO2/TiO2 composite resulted from the benefit ECL effect of interface heterojunction in composite.

A new D-A (Donor-Accept) type N -(1,2,4-triazolyl)- N ′-(2-ethylhexyl) naphthalenediimide ( L ) was synthesized. AgL 2 PF 6 ( 1 ) and AgL 2 NO 3 ( 2 ) were obtained through the reactions of L with AgPF 6 and AgNO 3 , respectively. All the compounds were fully characterized. Optical, electrochemical properties and electrogenerated chemiluminescence (ECL) were systematically investigated. Those dual fluorescent emissions for L , short wavelength (SW) and long wavelength (LW) emission bands, are rationally explained by the planar intramolecular charge transfer (PICT) model. All the compounds display anodically shift reduction waves with positive reduction potential, compared to its parent compound, Naphthalene bisimide (NBI). It is very interesting that the ECL intensity of the complexes is successfully increased, which is 20 times larger than that of L , explaining that the radical anions of the complexes are stabilized by coordinating L with Ag(I) ion. The results provide a new approach to study ECL materials.

By dipping-lifting in sol–gel solution and reducing process, the graphene/TiO 2 composite film on the glass plate was first prepared. Then, the Ag/graphene/TiO 2 composite film was fabricated by interface reaction with AgNO 3 and N 2 H 4 ·H 2 O on the surface of graphene/TiO 2 composite film. The characterization results show that the uniform porous TiO 2 film is made up of the anatase crystal, and the Ag/graphene/TiO 2 composite film is constructed by doping or depositing graphene sheets and Ag nanoparticles on the surface of TiO 2 film. The photoelectrochemical measurement results indicate that the Ag/graphene/TiO 2 composite film has an excellent photoelectrochemical conversion property.

A novel hydrothermal method has been developed for the preparation of Bi2Se3 nanotubes with the laminar surface. The method is based on the template-engaged synthesis in which the as-prepared Se nanotubes were used as template reagent. The morphology, constitution and crystalline phase of the products as-obtained were characterized by SEM, XRD and XPS. On the basis of a series of experiments and characterizations, the effect factors (such as the reaction temperature and the atom ratio of Bi and Se in the precursors) and the formation mechanism of the Bi2Se3 nanotubes were discussed. Furthermore, the electrochemical property of the Bi2Se3 nanotubes was determined by the voltammetric technique, and the significant results were obtained.

The structures of four novel organic–inorganic hybrid dyes, namely trans-4-(4′-(N,N-Dialkylaminostyryl))-N-Methyl-pyridinium[Mo6O192−] [alkyl = Et(POM1), Pr(POM2), n-Bu(POM3) and Me, hydroxyethyl(POM4)], were characterized by single crystal X-ray diffraction analysis. Hybridization of the organic chromophores with polyoxometalate enhanced their two-photon absorption cross sections and thermal stability. The linear optical properties of the hybrid dyes were investigated using absorption and fluorescence spectra in both the solution and solid states. The two-photon absorption cross section δ and coefficient β were obtained using the Z-scan technique. Correlations between dye structure and optical property were investigated.

Cyclic voltammetry (CV), IR spectroelectrochemistry cyclic voltabsorptometry (CVA) and derivative cyclic voltabsorptometry (DCVA) technique were used to investigate the electrochemical character of a representative quinone, p-benzoquinone (BQ), in aprotic media, organic-water mixed solvent, unbuffered acidic aqueous ([H + ] + ] > [BQ]). Several well-separated IR absorption peak pairs, 1656, 1316; 1502, 1340; and 1230, 1473 cm −1 , corresponding to redox transitions (BQ, BQ − , BQ 2− ), are observed and can be used to trace the concentration of BQ, BQ − and BQ 2− independently during CV scan. Based on CVA and DCVA techniques, it is clearly distinguished that each step of the two consecutive electron transfer process of BQ in unbuffered neutral aqueous takes place, although only one CV wave is experimentally observed during CV scan. Direct evidence of hydrogen-bonding (H-bonding) forming between BQ 2− (BQ − ) and H 2 O in unbuffered neutral water and that between BQ and H 3 O + in strong acidic solution are observed. The results of IR CVA and DCVA not only help us understand the fundamental factors of H-bonding and protonation on redox mechanism of BQ, but also draw the entire map of the electrochemical reduction of BQ in different solution.

In this paper, the TiO 2 /HS–CH 2 –COOH/Cu 3 Se 2 composite film photoanodes were fabricated on conducting glass plates. Cu 3 Se 2 nanoparticles were used as the sensitizer and the bi-functional modifier HS–CH 2 –COOH was used at the interface between Cu 3 Se 2 and TiO 2 films to improve the properties of the film photoanode. The characterization results show that the sol–gel prepared anatase TiO 2 film has a compact and uniform surface, while the tetragonal Cu 3 Se 2 film has a coarse surface which is made up of uniform elongated particles. The photoelectrochemical experimental results indicate that the TiO 2 /HS–CH 2 –COOH/Cu 3 Se 2 composite film photoanodes have a good photovoltaic property.

A novel chemical method has been developed for the preparation of the PbTe nanorods. The method is based on the template-engaged synthesis in which the Te nanorods as-prepared were used as template reagent. On the basis of a series of experiments and characterizations, the effects of the reaction time and temperature on the product were discussed, respectively. Besides the synthesis, the electrochemical property of the PbTe nanorods was determined, and useful results were obtained.

A novel chemical method has been developed for the preparation of PbSe nanotubes. The method is based on the template-engaged synthesis in which the as-prepared Se nanotubes were used as template reagent. On the basis of a series of experiments and characterizations, the effect factors and the formation mechanism of the PbSe nanotubes were discussed. Furthermore, the electrochemical property of the PbSe nanotubes was studied.

Coupling TiO2 with a narrow band gap semiconductor acting as the photosensitizer has attracted much attention in solar energy exploitation. In this work, the porous TiO2 film was first formed on the conducting glass plate (CGP) substrate by the decomposition of polyethylene glycol (PEG) mixing in titanium hydroxide sol at 450°C. Then, the TiO2/Ag2Se interface composite film was fabricated by interface reaction of AgNO3 with NaSeSO3 on the activated surface of porous TiO2 film. The results of SEM and XRD analyses indicated that the porous TiO2 layer was made up of the anatase crystal, and the Ag2Se layer was made up of congregative small particles that have low-temperature α-phase structure. Due to its efficient charge separation for the photo-induced electron-hole pairs, the TiO2/Ag2Se interface composite film as-prepared has good photovoltaic property and high photocurrent response for visible light, which have been confirmed by the photoelectrochemical measurements.

Two new metal-centered ferrocene complexes Ni(SCN)2(L)4 (1) and Cu(OAc)2(L)2 (2) (L = 1-[1-ferrocenylmethyl]imidazole) have been synthesized and characterized by elemental analysis, single crystal X-ray diffraction analysis, spectroscopic and cyclic voltammetric measurements. The geometry of Ni(II) in 1 is octahedral, with four ligands in the equatorial plan and two thiocyanate anions at the axial site, while that of Cu(II) in 2 is a distorted octahedron formed by two chealted OAc− and two ligands. Single crystal X-ray diffraction studies reveal that there is partial electron delocalization from ferrocene to imidazole in the two complexes. Electrochemical measurements exhibit that complexes 1 and 2 undergo similar reversible one electron redox processes, suggesting that the ferrocene moieties are equivalent and there are no interactions among them.

The synthesis, structure, and single- and two-photon spectroscopic properties of a series of pyrimidine-based (bent-shaped) molecules are reported. All these stable heterocyclic compounds are fully characterized, and exhibit intense single- and two-photon excited fluorescence (SPEF and TPEF) over a wide spectral range from blue to red, with the spectral peak position of the SPEF being basically the same as that of the TPEF. The well-conjugated pi-systems, observed from the crystal structure, indicate the charge transfer feature of the ground state. Meanwhile, the theoretical and experimental studies indicate that the charge transfer from donor to acceptor is greatly enhanced in the excited states and the different substituted donor groups on the pyrimidine have a large effect on the optical and electrochemical properties. Based on typical structure data and comprehensive spectral data, the following structure-property relationships can be determined: for such bent-shaped chromophores, the absorption and the fluorescence wavelength maximum of the SPEF and TPEF, and two-photon absorption cross sections show a similar trend with increasing electron-donating strength of the corresponding terminal group and the number of branches, while the average bond lengths of the pi-linkage and HOMO-LUMO energy levels show an inverse trend. Experimental data and theoretical calculation provide a coherent picture. With these findings, bent-shaped quadrupolar chromophores combining peak TPA cross sections (up to 2280 GM), broad TPA bands throughout the whole 700-900 nm range, and high fluorescence quantum yields could, thus, be obtained. Such compounds are of particular interest for TPEF microscopy, as well as optical data storage in the visible and NIR regions. A data recording experiment proved the potential application of these materials.

Ortho-CuAgSe nanotubes were facilely synthesized through a nanotube–nanotube transformation process in aqueous solution at room temperature. The products as-obtained were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectra (XPS) and thermogravimetric (TG)/differential scanning calorimetric (DSC). On the basis of a series of the experiment results, the formation mechanism of ortho-CuAgSe nanotubes was proposed. From kinetics and energetics, it had been demonstrated that the exchange of univalent cation between ortho-Ag2Se (orthorhombic phase Ag2Se) nanotubes and ortho-Cu2Se nanotubes in the formation process of ortho-CuAgSe nanotubes was feasible in mild condition. Furthermore, the electrochemical property of the nanotubes as-obtained was studied by the voltammetric technique.

A novel sulfur-terminal Zn(II) complex Zn(S)(2)L (L = N-hexyl-3-{2-[4-(2,2':6',2''-terpyridin-4'-yl)phenyl] ethenyl}carbazole) was obtained by a facile solvothermal process. The unique feature in this new reaction design is the use of ZnS nanocrystals as a precursor and bulky chromophoric L as an ancillary ligand. The versatility of the two terminal sulfur atoms is relevant to biological system. The resulting Zn(S)(2)L complex shows two-photon excited fluorescence (TPEF), which has been proven to be potentially useful for two-photon microscopy imaging in living cells. In addition, cytotoxicity tests showed that the low-micromolar concentrations of Zn(S)(2)L did not cause significant reduction in cell viability over a period of at least 24 h and should be safe for further biological studies.

The CeO2/TiO2 and TiO2/CeO2 interface composite films were prepared on glass substrates by the sol–gel process via dip-coating and calcining technique. The scanning electron microscopy (SEM) revealed that the TiO2 layer has a compact and uniformity glasslike surface with 200 nm in thickness, and the CeO2 layer has a coarse surface with 240 nm in thickness. The X-ray diffractometer (XRD) analysis showed that the TiO2 layer is made up of anatase phase, and the CeO2 layer is structured by cubic fluorite phase. Through a series of photo-degradation experiments, the relationship of the photocatalytic activity with the constituents of the films was studied. In virtue of the efficient interfacial charge separation via the process of electron transfer from TiO2 to CeO2, the photocatalytic activity of the CeO2/TiO2 composite film is high. Contrarily, the photocatalytic activity of the TiO2/CeO2 composite film is low, due to its inert surface made up of CeO2 with broad bandwidth. Apart from the effect of the film structure, the effect of film thickness on photocatalytic activity was also discussed.

A series of ferrocene-substituted thiophenes, 2-ferrocenylthiophene, 2,5-diferrocenylthiophene and 2,3,5-triferrocenylthiophene have been synthesized. The electron transfer mechanism during redox process of the ferrocenyl complexes was studied by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and rapid-scan time-resolved FT-IR spectroelectrochemistry (RS-TRS FT-IR). Electrochemistry and RS-TRS FT-IR spectroelectrochemistry results indicated the redox process of 2,5-diferrocenylthiophene and 2,3,5-triferrocenylthiophene involved two and three consecutive one-electron steps, respectively. IR absorption peaks arisen from intermediate appearing and disappearing on the experimental time scale in the oxidation and reduction process of 2,5-diferrocenylthiophene and 2,3,5-triferrocenylthiophene were clearly observed by the RS-TRS FT-IR spectroelectrochemistry. A kinetics simulation experiment, based on the results of RS-TRS FT-IR spectroelectrochemistry, was conducted to give the kinetics parameters of 2,5-diferrocenylthiophene.

A simple chemical method has been developed for the preparation of fringy CdSe wurtzite nanocrystals. The method is based on the template-engaged water-thermal synthesis in which the Se nanotubes were used as template reagent and NH3.H2O as reducer. The products were characterized by SEM, TEM, XRD, and XPS analyses. On the basis of a series of experiments and characterizations, the effect factors and the formation mechanism for the CdSe nanocrystals were discussed. Furthermore, the photochemical, electrochemical, and electrogenerated chemiluminescence (ECL) properties of the CdSe nanocrystals were studied and significant results were obtained.

A rapid chemical method has been developed for the synthesis of the Ag2Te nanorods with monoclinic crystalline phase. The method is based on the template-engaged synthesis in which the Te nanorods were used as template reagents. On the basis of a series of experiments and characterizations, the effect factors and the formation mechanism of the Ag2Te nanorods were discussed. Furthermore, the electrochemical property of the Ag2Te nanorods was determined by the voltammetric technique.

The electrochemical behavior and the electrogenerated chemiluminescence (ECL) of the crystalline CuSe nanotubes as-prepared were present in this paper. The effect factors on these properties of the CuSe nanotubes, such as scan rate, scan potential scope and the acidity of electrolyte solution, were thoroughly studied. The results show that the electroactivity of the CuSe nanotubes could be enhanced in acidic or alkaline solution. With pulse potential scan, the CuSe nanotubes could produce excellent ECL in neutral aqueous solution.

A novel ferrocene derivative which has four stereo centers has been prepared by an efficient synthetic method based on a solvent-free reaction. The compound was characterized by IR, 1H-NMR, 13C-NMR, ESI-MS, single crystal X-ray diffraction and TG analysis. The crystal structure shows that the cyclohexyl group is in a chair conformation and the two ferrocenyl moieties are nonequivalent. There are two intramolecular hydrogen bonds and two intermolecular hydrogen bonds in the compound, which involve two hydroxyls and generate a dimer, respectively. The electrochemical properties of the compound are discussed.

Aiming to enhance the use of solar energy, novel SeO 2 /TiO 2 nanocomposite was prepared by water bathing and calcining. Based on the characteristic of SeO 2 and TiO 2 , the work mechanism of the nanocomposite was discussed. The products as obtained were characterized by SEM, HRTEM, EDX, XRD, XPS, LRS and UV-vis. The results shown that the SeO 2 /TiO 2 nanocomposite is a hopeful form for improving the practicability of TiO 2 .

The novel compound, 3-(E)-ferrocenyl-vinyl-N-hexylcarbazole (FVHC) was first synthesized and fully characterized by elemental analysis, IR, 1H-NMR, single-crystal X-ray diffraction, ultraviolet (UV) absorption, cyclic voltammograms (CV) and optical limiting (OL) measurements. The result of single crystal X-ray diffraction for the compound reveals that the ferrocenyl and carbazole groups are approximately coplanar, and bridged by double-bond with E configuration, showing that there is a well-delocalized π-electron system in the molecule. The electrochemical investigation indicated that the electron in the FVHC may partially be delocalized over the π-conjugated system and CT process in functionalized carbazole systems. Besides, the compound exhibited strong UV absorption and large optical limiting effect, indicating promising potential applications as useful OL materials.

The design and tests of a low temperature optically reflected absorbance cell for in situ FTIR spectroelectrochemistry is discussed. It works very well in the temperature range from −100 to +25 °C with temperature control precision within ±0.5 °C. The cell is facile cleaning and convenient manipulation. Besides, it can work, successively, for long time with filling the Dewar flask with liquid N2. The electrochemical performance of the cell is characterized in cyclic voltammetry with K4Fe(CN)6 at room temperature and in steady-state voltammetry with ferrocene at low temperature. The low temperature applicability of the cell for in situ FTIR is demonstrated to observe the electrogenerated intermediate of 1,4-bis(2-ferrocenylvinyl)benzene (p-(Fc–CH CH)2BZ).

The electron transfer to or from molecules containing multiple redox centers has been extensively investigated. Rapid scan time-resolved FT-IR-RAS spectroelectrochemistry was used to investigate the electron-transfer mechanism in this report. The electron transfer of two typical compounds, 1,4-benzoquinone and 1,4-bis(2-ferrocenylvinyl)benzene, was examined with this method. Although the two compounds show two-electron transfer in the redox process, 1,4-benzoquinone exhibits two single electron waves while 1,4-bis(2-ferrocenylvinyl)benzene exhibits a single wave in cyclic voltammetric experiments. The IR absorption of the intermediate, BQ*- and p-(Fc-CH=CH)+2-benzene, at 1506 and 1589 cm(-1), respectively, appeared and disappeared on the experimental time scale in the oxidation and reduction process was observed. In the oxidation process of the p-(Fc-CH=CH)2-benzene molecule, one Fc was oxidated to Fc+ first and the electron-withdrawing ability of Fc+ was stronger than that of Fc, which resulted in the D-pi-A structure and the band at 1589 cm(-1) becoming visible. Then as the oxidation continues, the other Fc was oxidated to Fc+ too, which resulted in the reforming of the symmetry of the benzene ring A-pi-A, so the band at 1589 cm(-1) disappeared. Similar phenomenon can be elucidated in the reduction process but the configuration type changed from A-pi-A to D-pi-A and finally to D-pi-D. Hence, not only 1,4-benzoquinone but also 1,4-bis(2-ferrocenylvinyl)benzene show two consecutive one-electron processes. In addition, it is observed that the existing time of the electrochemical reaction intermediate (BQ*- and p-(Fc-CH=CH)+2-benzene) is prolonged at low temperatures due to slow reaction kinetics.