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[Display omitted] • Polyurethane elastomer (TPU) is prepared firstly as an artificial SEI of Li metal anode. • IPDI hard chain segment and soft link forging PEO jointly improve elasticity and ion conducting channel of the TPU. • TPU coated Li foil can be stable in air for 45 min without obvious deterioration. • The elastic modulus of TPU is up to 105 Pa and the elongation at break is up to 2854%. • TPU-Li||LFP cell delivers a long cyclelife with 90% retention after 1500 cycles at 5 C. Compared with other anode materials, Li metal anode has higher capacity density and lower electrode potential, which has been considered as one of the most promising anode materials. However, the unstable solid electrolyte interface (SEI) leads to Li dendrite growth and the infinite volumetric expansion of Li metal, which seriously hinders the stability and cycle life of Li metal batteries (LMBs). Here, a polyurethane elastomer (TPU) material with high elasticity and air stability is used as the artificial SEI of Li metal anode. Its designed synergistic effect of soft chain forging and hard chain segments not only gives TPU artificial SEI layer good electronic insulation, Li ion conductivity, Li dendrite growth inhibition, high elastic modulus and flexibility to adapt to Li volume expansion, but also has a significant air protection effect on the Li metal surface, so that the TPU coated Li foil will not occur obvious oxidation phenomenon after being placed in air for 45 min. The Li symmetric battery modified by TPU achieved a stable and long-term cycle performance of 1300 h at 1 mA/cm2, it can also cycle stably at a high current density of 10 mA/cm2. The Coulomb efficiency of the modified Li/Cu half-cell maintains at above 97% after 400 cycles. In addition, the full cell with LiFePO 4 cathode also delivers a very excellent long cycle stability with 90% capacity retention after 1500 cycles at 5 C. This surface modification strategy of SEI on lithium anode has has great research value and will help to improve the widely application of LMBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • I-CNT with enhanced electronic conductivity is reported as a multifunctional sulfur skeleton material. • I-CNT skeleton boosts adsorption effect and conversion reaction kinetics of LiPSs. • DFT calculation, quasi in-situ EIS and in-situ Raman spectroscopy reveal the polysulfides conversion mechanism. • The Li 2 S potentiostatic deposition i - t curves also confirm the improved liquid–solid reaction kinetics. • I-CNT@S exhibits satisfactory cycle stability of 528.9 mAh g−1 at 2C after 700 cycles. Compared with lithium-ion batteries (LIBs), lithium-sulfur batteries (LSBs), based on electrochemical reactions involving multi-step 16-electron transformations provide higher specific capacity (1672 mAh g−1) and specific energy (2600 Wh kg−1), exhibiting great potential in the field of energy storage. However, the inherent insulation of sulfur, slow electrochemical reaction kinetics and detrimental shuttle-effect of lithium polysulfides (LiPSs) restrict the development of LSBs in practical applications. Herein, the iodine-doped carbon nanotubes (I-CNTs) is firstly reported as sulfur host material to the enhance the adsorption-conversion kinetics of LSBs. Iodine doping can significantly improve the polarity of I-CNTs. Iodine atoms with lone pair electrons (Lewis base) in iodine-doped CNTs can interact with lithium cations (Lewis acidic) in LiPSs, thereby anchoring polysulfides and suppressing subsequent shuttling behavior. Moreover, the charge transfer between iodine species (electron acceptor) and CNTs (electron donor) decreases the gap band and subsequently improves the conductivity of I-CNTs. The enhanced adsorption effect and conductivity are beneficial for accelerating reaction kinetics and enhancing electrocatalytic activity. The in-situ Raman spectroscopy, quasi in-situ electrochemical impedance spectroscopy (EIS) and Li 2 S potentiostatic deposition current–time (i-t) curves were conducted to verify mechanism of complex sulfur reduction reaction (SRR). Owing to above advantages, the I-CNTs@S composite cathode exhibits an ultrahigh initial capacity of 1326 mAh g−1 as well as outstanding cyclicability and rate performance. Our research results provide inspirations for the design of multifunctional host material for sulfur/carbon composite cathodes in LSBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • PTFE-based dry-processed technology is used to prepare flexible Li 6 PS 5 Cl membrane and FeS 2 composite cathode membrane. • Due to the robust adhesion of PTFE, intimate contact is obtained at 100 MPa which is one-fifth of conventional pressure. • PTFE attaches the electrochemical sluggish products to an ion–electron conductive network to improve cyclic stability. • The flexible FeS 2 -ASSLBs exhibit excellent cyclic stability under the stack pressure of 100 MPa. All-solid-state lithium batteries (ASSLBs) are considered promising energy storage systems due to their high energy density and inherent safety. However, scalable fabrication of ASSLBs based on transition metal sulfide cathodes through the conventional powder cold-pressing method with ultrahigh stacking pressure remains challenging. This article elucidates a dry process methodology for preparing flexible and high-performance FeS 2 -based ASSLBs under low stack pressure by utilizing polytetrafluoroethylene (PTFE) binder. In this design, fibrous PTFE interweaves Li 6 PS 5 Cl particles and FeS 2 cathode components, forming flexible electrolyte and composite cathode membranes. Beneficial to the robust adhesion, the composite cathode and Li 6 PS 5 Cl membranes are tightly compacted under a low stacking pressure of 100 MPa which is a fifth of the conventional pressure. Moreover, the electrode/electrolyte interface can sustain adequate contact throughout electrochemical cycling. As expected, the FeS 2 -based ASSLBs exhibit outstanding rate performance and cyclic stability, contributing a reversible discharged capacity of 370.7 mAh g−1 at 0.3C after 200 cycles. More importantly, the meticulous dQ/dV analysis reveals that the three-dimensional PTFE binder effectively binds the discharge products with sluggish kinetics (Li 2 S and Fe) to the ion–electron conductive network in the composite cathode, thereby preventing the electrochemical inactivation of products and enhancing electrochemical performance. Furthermore, FeS 2 -based pouch-type cells are fabricated, demonstrating the potential of PTFE-based dry-process technology to scale up ASSLBs from laboratory-scale mold cells to factory-scale pouch cells. This feasible dry-processed technology provides valuable insights to advance the practical applications of ASSLBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bifunctional Cu-CuBr substrate was first constructed by electrochemical methods. • It exhibits high sensitivity and excellent stability (more than 1 year) • MOFs improve SERS and catalytic performance by changing surface properties. • In-situ SERS monitoring of the photocatalytic dehalogenation reaction process. • In-situ SERS reveals the role of MOFs on photocatalytic selectivity. Photocatalytic reactions using copper-based nanomaterials have emerged as a new paradigm in green technology. Selective photocatalysis is very important for improving energy utilization efficiency, and in order to directional improve catalytic selectivity, it is necessary to understand the mechanism of interfacial reactions at the molecular level. Therefore, a unique bifunctional Cu-CuBr substrate is first fabricated via an electrochemical method, which overcomes the instability of traditional copper-based materials and endows high surface-enhanced Raman spectroscopy (SERS) sensitivity and photocatalytic performance and can be stored stably for more than a year. Further modification of the surface with Metal-Organic Frameworks (MOFs) containing carboxyl functional groups can significantly tune the surface properties of the substrate. This increases the adsorption of cationic dyes to improve the SERS effect, and 10−10 M methylene blue can easily be detected with this substrate. Surprisingly, in-situ SERS monitoring of the interfacial photocatalytic dehalogenation reaction of aromatic halides through its intrinsic SERS effect reveal two competing selective reaction pathways, self-coupling and hydrogenation. Typically, the SERS spectra reveal that the latter's selectivity was greatly enhanced after MOFs modification, and the yield rate of the hydrogenated product increased from 27.6 % to 46.9 % (selectivity increased from 32.7 % to 51.5 %). This proves that the surface properties of catalysts, especially the affinity for reaction intermediates, can effectively regulate catalytic selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyurethane elastomer (TPU) is designed firstly as a solid polymer electrolyte (SPE) for LMBs. • Soft chain forging PEO and hard chain segments IPDI enhance Li+ conductivity, elastic modulus and flexibility of the SPE. • The Li 2 S additive promotes in-situ generatation of LiF at the Li/PEO interface. • Smooth and stable interface enables Li symmetric battery a long cycle of 1400 h at 0.1 mA/cm2. • The Li||LiFePO 4 cell exhibits an excellent capacity retention rate of 80% after 500 cycles at 1C. Li metal anodes have high specific capacity and low electrode potential, and have always been considered as one of the most promising anode materials. However, the growth of Li dendrites, unstable solid electrolyte interface layer (SEI), severe side reactions at the Li/electrolyte interface, and infinite volume expansion of the Li anode seriously hinder the practical application of solid-state Li metal batteries (LMBs). Herein, we report a polyurethane elastomer (TPU) material with high elasticity and interfacial stability as a solid polymer electrolyte (SPE) for LMBs. The synergistic effects of its designed soft chain forging (PEO) and hard chain segments (IPDI) can enhance Li ion conductivity, elastic modulus and flexibility of the SPE to settle the challenges of the Li metal anodes. Moreover, Li 2 S, as a solid-state electrolyte additive, is able to effectively inhibit the occurrence of side reactions at the interface between Li metal and SPE, promote the decomposition of N(CF 3 SO 2) 2 − and in-situ generation of LiF with low Li+ diffusion barrier and excellent electronic insulation, achieving rapid Li ion transport and uniform Li deposition. As a result, stable cycle of up to 1400 h has been achieved for a Li||TPU-Li 2 S||Li battery at 0.1 mA/cm2 at 50 ℃, accompanied with a stable cycling performance of 350 h at a higher current density of 0.5 mA/cm2. Finally, the LiFePO 4 ||TPU-Li 2 S||Li full battery exhibits an excellent cycling performance with a capacity retention rate of 80 % after 500 cycles at 1C. This simple and low-cost strategy provides novel design thoughts for practical application of high-performance SPEs in stable and long-life LMBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeS 2 @C/rGO@Li 7 P 3 S 11 cathode with ion–electron conduction network is well designed. • The dual-carbon framework serves as electron transmission bridge and Li 7 P 3 S 11 acts as the ion conduction network. • The dual-carbon framework and Li 7 P 3 S 11 coating layer preserve structural integrity and improve ion–electron conduction. • The FeS 2 @C/rGO@Li 7 P 3 S 11 cathode exhibit an excellent cycle and rate performance in ASSLBs. The all-solid-state lithium batteries (ASSLBs) with high energy density are considered to be one of the most promising candidates for next-generation lithium battery systems. Nevertheless, the low ionic and electronic conduction inside the cathode and the poor interfacial contact of the cathode/electrolyte seriously impede the large-scale application of ASSLBs. In this work, a novel multiple ion–electron conductive network is constructed on the FeS 2 cathode to realize a high-energy all-solid-state battery. The internal disordered carbon matrix acts as electronic network to accelerate the electronic transmission. Meanwhile, reduced graphene oxide (rGO) tightly wrapping FeS 2 /C microspheres' surface serves as external electronic pathway. Moreover, the in-situ formed Li 7 P 3 S 11 electrolyte infiltrates into the nanoparticles to improve lithium-ion transport kinetics. Therefore, the dual-carbon framework and Li 7 P 3 S 11 coating layer strategies significantly enhance ion–electron transport kinetics and improve interfacial contact during cycling. As expected, the FeS 2 @C/rGO@Li 7 P 3 S 11 cathode exhibits excellent rate capability and cycling stability, showing a reversible discharge capacity of 350.3 mAh/g at 0.5C after 200 cycles. More importantly, ex-situ XPS and dQ/dV results reveal that the synergistic effect of dual-carbon frameworks and Li 7 P 3 S 11 coating layer not only provides fast electron–ion transfer channels, but also wraps the reaction products with poor electrochemical activity such as Fe0, FeS y , and S to accelerate the reaction kinetics and strengthens the reaction reversibility. This work provides valuable insights for improving the electrochemical performance and understanding the reaction mechanism of the conversion-type metal sulfide cathodes in ASSLBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synergy between Ni 12 P 5 nanocrystals and NSG reinforces the HER/IRR activity. • Ni 12 P 5 /NSG yields a low overpotential of 133 mV in alkaline HER. • Ni 12 P 5 /NSG gives an impressive photovoltaic performance. • The catalytic mechanism for HER/IRR was revealed by DFT calculation. Designing high-efficient bifunction catalysts with excellent catalytic activity and enhanced charge-transfer capability in both alkaline hydrogen evolution reaction (HER) and triiodide reduction reaction (IRR) is of utmost significance to advance the development of green hydrogen production and photovoltaics, respectively, yet remains a crucial challenge. Here, highly dispersed and small-sized Ni 12 P 5 nanocrystals with narrow size distribution was well attached on the surface of N, S co-doped graphene (Ni 12 P 5 /NSG) by the facile hot-injection method. As expected, the optimized Ni 12 P 5 /NSG requires a relatively low overpotential of 132.94 ± 0.08 mV to deliver a current density of 10 mA cm−2 in alkaline condition, accompanied with remarkable long-time durability with negligible attenuation over 50 h. Density functional theory (DFT) calculations revealed that the positively synergic effect between Ni 12 P 5 and NSG are in favor of modulating the rate determining step of the dissociation of H 2 O to *(OH-H), thereby upgrading its HER activity. When used as the counter electrode catalyst for IRR in DSSCs, the resultant Ni 12 P 5 /NSG exhibits extraordinary Pt-like catalytic activity and well electrochemical stability in iodide-based electrolyte, delivering a high photoelectric conversion performance (PCE) comparable to Pt. The improved PCE can be attributed to the accelerated interfacial charge-transfer capability around active sites for facilitating the reaction kinetics of IRR, as demonstrated by DFT calculations. This work provides an effective strategy for synthesizing cost-effective composites with multi-active sites and offering valuable insight into the structure-performance relationship, which is conducive to guide the synthesis of promising catalysts in the energy conversion field. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional polymer electrolyte (MPE) buffer layer is constructed on LLZTO surface through an in-situ crosslinking strategy. • MPE improves interface contact at both sides of LLZTO and widen electrochemical window. • MPE@LLZTO facilitates uniform Li+ deposition/exfoliation and inhibits dendrite growth. • The Li symmetrical and NCM523 full cells exhibit excellent cycle performance at 30 °C. The garnet Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 (LLZTO) is one of the most promising electrolytes for commercial application since of its high ionic conductivity and good stability to Li. Nevertheless, the poor electrolyte/electrode interface contact enlarges the interface impedance of all-solid-state battery (ASSB). Herein, a multifunctional polymer electrolyte (MPE) interface buffer layers are formed on both sides of LLZTO surface through an in-situ crosslinking strategy to improve the interface contact with electrodes, which can facilitate uniform Li+ deposition/exfoliation and inhibit the growth of lithium dendrites as evidenced by the reduced interface impedance (103.4 Ω cm2), the increased critical current density (CDD, 1.2 mA cm−2) and 950 h stable cycle of Li symmetric cells at 0.7 mA cm−2, 0.7 mA h cm−2. Besides, the MPE layer can reduce the magnitude of electric field at the interface and widen the electrochemical window (0∼5.2 V). The stable interface of the LLZTO@MPE/cathode enables the full cells matching with the LiFePO 4 (LFP) and LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) cathodes to deliver superior electrochemical performances. Specifically, the Li/MPE@LLZTO@MPE/LFP delivers a capacity retention rate of 87% after 200 cycles at 1 C. When it's matched with the NCM523 cathode, a capacity retention rate of 98% is retained after 100 cycles at 1 C. This work provides an effective and simple way to build good-interface-contact and long-lifespan garnet solid-state lithium metal batteries (SSLMBs). [ABSTRACT FROM AUTHOR]

[Display omitted] High-energy–density lithium-rich Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 is regarded as one of the most promising cathode materials for lithium-ion batteries. However, its practical application is restricted by critical kinetics drawbacks and poor low-temperature electrochemical performances. In this research, Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 submicron particles coated by a Li 7 La 3 Zr 2 O 12 (LLZO) layer and co-doped by La/Zr cations has been fabricated via a facile one-pot sol–gel technique and subsequent heat treatment. The coating LLZO layer with a few nanometers is able to build a rapid lithium-ion transport channel for adjacent particles and suppress severe side reactions between active material and the electrolyte. Moreover, large-radius La/Zr cations co-doping can broaden the diffusion paths of lithium ions, hinder the detrimental structural transformation, and improve the electrochemical structure stability of the cathode during repeated cycles. Owing to numerous merits from this multifunctional surface modification strategy, the modified Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 composite exhibits the significantly decreased interface impedance, enhanced Li+ diffusion kinetics and mitigated phase transformation, as well as excellent low-temperature electrochemical performance. It can contribute ultrahigh capacities of 173.8 mAh g−1 at −10 ℃ and 134.1 mAh g−1 at −20 ℃, respectively, displaying great application prospects of Li-rich cathode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel PEG-SnS 2 /rGO composite is prepared as anode material for SIBs. • The interlayer spacing of SnS 2 layers is enlarged to 0.92 nm due to the insertion of PEG. • SnS 2 nanoparticles are uniformly grown on graphene skeleton by C S covalent binding. • The expanded layer spacing and strong affinity promotes reaction kinetics and capacitive contribution. • Excellent rate performance with a high capacity of 720 mAh g−1 at 5 A g−1 is delivered. As a kind of negative electrode material for sodium-ion batteries (SIBs), tin-based active compounds have attracted numerous research efforts in recent years due to relatively high theoretical capacity. However, sluggish reaction kinetics for large-radius sodium ions hinders the practical application of layered tin-based anodes such as tin disulfide (SnS 2) in SIBs. In this study, polyethylene glycol (PEG) is introduced as an intercalant and reduced graphene oxide (rGO) is utilized as the substrate to prepare a novel PEG-SnS 2 /rGO composite with expanded layer spacing (0.921 nm) through a facile hydrothermal process. SnS 2 flakes in a size range of 50–100 nm are uniformly grown on the graphene sheet, the C S covalent bonding demonstrates a tight connection between the active SnS 2 particles and the graphene skeleton, which is conductive to convenient charge transfer during the electrochemical process. Owing to the significantly improved sodium ions transport kinetics and fast electronic conductive network, the PEG-SnS 2 /rGO composite presents a high capacitance contribution of 90.69% at a scan rate of 0.6 mV s−1. It delivers a high reversible capacity of 960.6 mAh g−1 at 0.1 A g−1, good cycling performance with 770 mAh g−1 remained after 100 charge/discharge cycles, and excellent rate capability with an ultrahigh capacity of 720 mAh g−1 at 5 A g−1. This work provides new insights into the design of a kinetically favorable anode material for SIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] In the semiconductor/molecule/metal system, enhancing the efficiency of the charge-transfer (CT) plays a pivotal role in improving the sensitivity of semiconductor-based surface-enhanced Raman scattering (SERS). In this work, use of SERS for detection of an enhanced CT in a chemically-etched Al-doped ZnO (AZO), 4-mercaptopyridine (MPy) molecule, and Ag nanoparticles (NPs) (AZO/MPy/Ag) sandwich structure is reported. A series of CT routes are proposed in the energy level diagram of AZO/MPy/Ag assemblies under the excitation line at 633 nm. Very interestingly, for the first of its kind, a significant CT route from the conduction band (CB) of AZO to the lowest unoccupied molecular orbital (LUMO) of MPy molecule is detected. This route can remarkably improve the degree of CT in the AZO/MPy/Ag system by about 48% compared with that of the ZnO/MPy/Ag system. Furthermore, the uniquely enhanced CT route is also further confirmed by alternative probe molecules like p-aminothiophenol (PATP) and 4-mercaptobenzoic acid (MBA). The discovery of this extra CT route will inevitably play an irreplaceable role in SERS enhancement through its participating in the CT enhancement mechanism. [ABSTRACT FROM AUTHOR]

• Heterostructured Mn 2 SnO 4 /SnO 2 @spherical graphene composite is reported. • Mn 2 SnO 4 /SnO 2 nanoheterostructures are sandwiched between spherical graphene shells. • Mn infiltration promotes SnO 2 dissolution-redeposition and heterostructure formation. • Heterostructures produce internal electric field to improve Li+ transport kinetics. • The difference between Mn 2 SnO 4 /SnO 2 @SG and SnO 2 @SG was compared and discussed. Sn-based metal oxides and composites have been widely investigated as candidate anodes for lithium-ion batteries. However, continuous capacity fade caused by serious volumetric expansion and crystal pulverization is often noticed during lithiation and alloying processes. In this study, we design a novel heterogeneous structural composite by constructing sandwich-structured graphene hollow spheres limited Mn 2 SnO 4 /SnO 2 heterostructures (Mn 2 SnO 4 /SnO 2 @SG), of which infiltration of Mn source promotes the dissolution-redeposition of SnO 2 in hollow-spherical graphene (SnO 2 @SG) and their in-situ transformation into Mn 2 SnO 4 ; and the uniform distributed Mn 2 SnO 4 and SnO 2 nanoparticles are adjacent each other to form heterostructure within the sandwiched graphene hollow spheres. By comparing with the single metal oxide SnO 2 @SG material, the influence of the microstructure, chemical composition, element valence state and electrochemical properties of the heterostructured Mn 2 SnO 4 /SnO 2 @SG is investigated. The results show that the construction of Mn 2 SnO 4 /SnO 2 heterostructure dramatically improves electronic/ionic transport kinetics and increases lithium storage reversibility, therefore leading to distinctly superior rate capability (823.8 mAh g−1 at 5 C) and cycling capacity. An ultra-high discharge capacity of 1180.4 mA h g−1 is maintained up to 100 cycles at 100 mA g−1. The promising electrochemical performances can be attributed to the sandwiched-structure hollow graphene spherical skeleton and the formation of unique Mn 2 SnO 4 /SnO 2 heterostructures. [ABSTRACT FROM AUTHOR]

Abstract: A simple and effective surface-enhanced Raman scattering (SERS)-based protocol for the detection of protein–small molecule interactions has been developed. We employed silver-coated magnetic particles (AgMNPs), which can provide high SERS activity as a protein carrier to capture a small molecule. Combining magnetic separation and the SERS method for protein detection, highly reproducible SERS spectra of a protein–small molecule complex can be obtained with high sensitivity. This time-saving method employs an external magnetic field to induce the AgMNPs to aggregate to increase the amount of atto610-biotin/avidin complex in a unit area with the SERS enhancement. Because of the contribution of the AgMNP aggregation to the SERS, this protocol has great potential for practical high-throughput detection of the protein–small molecule complex and the antigen–antibody immunocomplex. [Copyright &y& Elsevier]

Abstract: We have employed the proposed Silica–Silver Core–Shell (SSCS) SERS-active substrates to detect four model proteins: lysozyme (a protein without chromophore), cytochrome c (a protein with chromophore of heme), fluorescein isothiocyanate (FITC)-anti human IgG (labeled with FITC) and atto610-biotin/avidin (recognition with labeled small molecules). SERS spectra of these proteins and Raman labels on the SSCS substrates show both high sensitivity and reproducibility, which are due to electromagnetic SERS enhancement with additional localization field within closely packed Ag nanoparticles decorated on the SiO2 nanoparticles and the aggregation of SiO2@Ag particles. We have found that the SERS intensities of atto610-biotin/avidin adsorbed on the SSCS substrates are about 20 times stronger than those from Ag plating on Au-decorated substrate. Moreover, the broad surface plasmon resonance (SPR) of the proposed substrates will extend SERS applications to more biological molecules with different laser excitations. [Copyright &y& Elsevier]

Abstract: One-dimensional (1D) ZnO/4-mercaptopyridine (4-Mpy)/Ag assemblies have been prepared by immersing ZnO rod arrays modified by 4-MPy into Ag nanoparticles colloid. Scanning electron microscopy (SEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) have been employed to investigate the formation process of ZnO/4-Mpy/Ag assemblies. It shows that 4-Mpy molecules are adsorbing on the surface of the ZnO rod arrays, then 4-Mpy molecules are partially dissociated from ZnO rod arrays by desorption and connect with Ag nanoparticles via the S atom. The analysis of XPS confirms the result obtained from Raman spectra of ZnO/4-Mpy/Ag assemblies. This research provides a direct spectroscopic evidence for the formation of mixed 1D ZnO/4-Mpy/Ag assemblies. [Copyright &y& Elsevier]

Abstract: Using an electroless replacement deposition method, large-area superhydrophobic metal substrate could be obtained. The superhydrophobic surfaces were prepared via a replacement reaction between copper substrate and HAuCl4 solution. The roughness of the copper substrate increased much after the replacement reaction. X-ray powder diffraction (XRD) pattern and energy dispersive X-ray (EDX) spectroscopy have proved that gold, CuCl and Cu2O formed on the surface of copper substrate after the replacement reaction. The surface showed remarkable superhydrophobic properties with a contact angle higher than 150 degrees without any modification with a self-assembled monolayer (SAM) of long chain thiol or perfluoro molecules. [Copyright &y& Elsevier]

Abstract: In this article, we report a simple wet-chemical method to prepare silver microflowers and large spherical particles. The formation of the two different microstructures of silver is based on the reduction of AgNO3 by para-phenylenediamine in aqueous medium at room temperature. The controlling of the silver microstructures can be achieved only by adjusting the concentration of the reactants. It is found that the two different silver microstructures display opposite wetting properties. Large spherical silver particles exhibit superhydrophilic properties with a contact angle (CA) of close to 0°, microflower-like silver particles exhibit highly hydrophobic properties with CA about 132°. X-ray diffraction (XRD), X-ray photoelectron spectra (XPS) and UV–vis spectra are used to characterize the chemical structure of the obtained products. [Copyright &y& Elsevier]

Abstract: Reported here is the study on the structure of Langmuir–Blodgett (LB) films of double-armed dibenzo-18-crown-6 contain biphenyl (DACE) which are newly synthesized and mixed with stearic acid (SA). In addition, the miscibility of the two compounds was also tested by the measurement of the surface pressure–area () isotherms of DACE and DACE/SA with various proportions. It is noted that there is no phase segregation in the mixed monolayer film of DACE/SA. Upon calculation of the excess surface area, it is concluded that the SA molecule can enter into the crown ether ring, while an 18C6 ring can host a maximum of one SA molecule. The difference of spectroscopic properties of DACE in LB films and bulk solution has been investigated by ultraviolet–visible (UV–vis) and Fourier-transfer infrared (FTIR) measurements. Molecules of DACE exist in the mixed LB films as monomers in contrast to those in the concentrated solution as aggregates. The hydrocarbon chains in DACE and DACE/SA LB films are tilted to the normal of the substrate surface, but perpendicular to the dipole moment of Cn the phenyl ethers and carboxylic ester of DACE, and the long axes of phenyl rings are aligned nearly perpendicular to the substrate surface. Infrared spectra of mixed LB films of DACE/SA present further evidence that the SA molecules enter into the crown ether rings of DACE. [Copyright &y& Elsevier]

Abstract: A simple method of the reduction of AgNO3 by copper foil in aqueous medium was used to prepare silver dendrites, which can be used as a novel good reproducible surface enhanced Raman scattering (SERS) active substrate. The SERS spectra of 4-pyridinethiol on this novel substrate reflected the different SERS activities on the minuteness and strong Ag dendrites. The electromagnetic coupling enhancement and chemical enhancement mechanisms are used to explain the SERS effect. [Copyright &y& Elsevier]

Abstract: A new SERS-active silver film prepared by directly depositing silver nanoparticles on glass is reported. The spontaneous reduction of Ag+ ions in -dimethylformamide (DMF) (in the absence of a protecting agent) leads to the deposition of silver nanoparticles on clean glass surfaces in contact with the solution. The observed optical micrographs and AFM images show that the arrangement of the nanoparticles is inhomogeneous and the particles appear to be closely packed. These films are shown to be excellent substrates for SERS measurements, demonstrating significant enhancement, good stability, and trace detection capability. The SERS enhancement of the silver films with different deposition times was compared and found that the 8-h film gives the largest enhancement ability with an enhancement factor estimated at about 109. It is also found that the silver films stored for 80 days in air show no significant degradation in their sensitivity. [Copyright &y& Elsevier]

Abstract: Langmuir monolayers and Langmuir–Blodgett (LB) films of 5,10,15,20-tetra-(p-chlorophenyl) terbium/gadolinium porphyrin hydroxyl compound (TbOH and GdOH) and their mixtures with stearic acid (SA) in a molar ratio of 1:1 were investigated by Brewster angle microscopy (BAM), ultraviolet–visible (UV–vis), and infrared (IR) spectroscopy and atomic force microscopy (AFM). π–A isotherms showed that well-defined Langmuir monolayers were formed at an air/water interface for the porphyrins and their mixture with SA. The BAM observations suggest that the interaction between the GdOH molecules is stronger than that between the TbOH molecules. This result can be further confirmed by the AFM measurements. After the introduction of SA, the interaction between the TbOH molecules is broken and thus two phases formed in the mixed LB film. However, it cannot break the stronger interaction between the GdOH molecules. Therefore, no phase separation is observed in the GdOH/SA LB film. IR reflection–absorption (RA) spectra showed that the COOH groups of SA are partly converted to COO- groups, suggesting that there is an interaction between MOH and SA in the films. This interaction leads the benzene rings of TbOH to rotate toward parallel to the substrate and those of GdOH to rotate toward perpendicular to the substrate. All these results have demonstrated that the central metal ions have great effects on the organization and formation of the films. [Copyright &y& Elsevier]

We investigated the fabrication of self-assembled monolayers of 5,10,15,20-tetra-(p-chlorophenyl)-porphyrin metal hydroxyl compounds (MOH; M=Gd, Tb, Er, Lu) on amino-terminated silanized quartz surfaces using ultraviolet–visible (UV–vis) and X-ray photoelectron spectroscopy (XPS). The orientation of MOH molecules in the films, the kinetics of the adsorption of MOH from a chloroform solution on an amino-terminated quartz substrate, and the stability of the metalloporphyrin films under natural light, UV light, and acidic and basic conditions were studied by UV–vis spectroscopy. The results indicate that the central metal is crucial in the formation of self-assembled porphyrin films and that the stability of the MOH SAMs also depends on the central metal. Under natural and UV light irradiation conditions, the stability of the MOH SAMs depends on the strength of the M&z.sbnd;N bonds between the central metal and pyrrole nitrogens or between the central metal and the axial ligand. In the acidic conditions, the UV–vis spectra of the MOH SAMs show decreases in the absorbance and blue shifts. These spectral changes lead us to suggest that the four M&z.sbnd;N bonds between the central metal and the pyrrole nitrogens of the porphyrins are cleaved and the resulted porphyrins are protonated under acidic conditions. Thus, it is likely that the protonated porphyrins and MOH form π−π complexes with a parallel stacking of the macrocycles through the electrostatic attractive interaction in the SAMs, resulting in the blue shifts of the Soret bands of the SAMs. [Copyright &y& Elsevier]

A novel method for the preparation of thin films of Ag nanoparticles is reported. Using mercaptoacetic acid as the stabilizing agent, AgI nanoparticles were prepared in aqueous solution. And based on electrostatic interactions, the thiol-passivated AgI nanoparticles were assembled in a self-assembled film by alternative deposition with a cationic polyelectrolyte. Then the AgI nanoparticles in the composite film were reduced by NaBH4, which resulted in the formation of a thin film of Ag nanoparticles. UV-visible spectra and X-ray photoelectron spectroscopy data confirmed the transformation from AgI to Ag. Atomic force microscopy (AFM) showed that the formed Ag nanoparticles distributed on the film homogeneously. Surface-enhanced Raman spectroscopy (SERS) measurement indicated that the prepared thin films could be used as effective SERS substrates. The reduction process was also carried out by UV light at selective surface regions, which resulted in the formation of patterned nanoparticle arrays. [Copyright &y& Elsevier]