We developed two-step solution-phase reactions to form hybrid materials of Mn3O4 nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. Mn3O4 nanoparticles grown selectively on RGO sheets over free particle growth in solution allowed for the electrically insulating Mn3O4 nanoparticles wired up to a current collector through the underlying conducting graphene network. The Mn3O4 nanoparticles formed on RGO show a high specific capacity up to ~900mAh/g near its theoretical capacity with good rate capability and cycling stability, owing to the intimate interactions between the graphene substrates and the Mn3O4 nanoparticles grown atop. The Mn3O4/RGO hybrid could be a promising candidate material for high-capacity, low-cost, and environmentally friendly anode for lithium ion batteries. Our growth-on-graphene approach should offer a new technique for design and synthesis of battery electrodes based on highly insulating materials.

Mn3O4-Graphene Hybrid as a High Capacity Anode Material for Lithium Ion Batteries

Besides the excellent high-temperature mechanical properties, Si3N4 and SiC based ceramics containing insulating or electrically conductive phase are attractive for their tunable dielectric propert...

Electromagnetic properties of Si–C–N based ceramics and composites

https://estudogeral.sib.uc.pt/bitstream/10316/10016/1/ficheiro.pdf

Surface modification and characterization of thermoplastic polyurethane

The hierarchically macro/micro-porous silicon–carbon–nitrogen (Si–C–N) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp2-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7 mg·g−1 and 1084.5 mg·g−1 for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous Si–C–N hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants.

/pdf/hierarchically-porous-silicon-carbon-nitrogen-hybrid-3m2nkqy68m.pdf

Hierarchically porous silicon–carbon–nitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes

Friction and wear phenomena encountered in mechanical systems with moving components are directly related to efficiency, reliability and life of the system. Hence, minimizing and controlling these phenomena to achieve the desired system performance is crucial. Among the numerous strategies developed for reducing friction and wear, coatings have been successfully utilized in various engineering applications to mitigate tribological problems. One of the benefits of coatings is that they may be fabricated using a variety of materials in several different forms and structures to satisfy the requirements of the operating conditions. Among many types, coatings that are comprised of a combination of materials in the form of a multilayer have been gaining much interest due to the added degree of freedom in tailoring the coating property. In this paper, the properties and development status of multilayer coating systems for tribological applications were reviewed with the aim to gain a better understanding regarding their advantages and limitations. Specifically, focus was given to Ti-based and Cr-based coatings since Ti and Cr were identified as important elements in multilayer coating applications. Emphasis was given to materials, design concepts, mechanical properties, deposition method, and friction and wear characteristics of these types of coatings.

https://link.springer.com/content/pdf/10.1007%2Fs40544-017-0181-7.pdf

Tribology of multilayer coatings for wear reduction: A review

Incorporation of carbon in a-Si:H network distorts the structural and enhances the optical band gap of HWCVD deposited a-SiC:H thin films. Besides C–C and C C bonds, C–H and Si–C bonds are mainly responsible for increasing the band gap from 2.4 to 3.5 eV. The presence of Si, O and defect clusters of sp2 carbon in the a-SiC:H matrix could indeed shift the diamond C(1s) peak position and broaden the FWHM of C(1s) peak. The C(1s) diamond peak is observed at 285.0 eV. In this work, we try to analyze the a-SiC:H network with the variation of C2H2 flow rate and the change in orbital behavior of sp2 and sp3 carbon in the presence of silicon and oxygen atom.

The analysis of carbon bonding environment in HWCVD deposited a-SiC:H films by XPS and Raman spectroscopy

Study of structural and electronic environments of hydrogenated amorphous silicon carbonitride (a-SiCN:H) films deposited by hot wire chemical vapor deposition

Electrochemical, bonding network and electrical properties of reduced graphene oxide-Fe2O3 nanocomposite for supercapacitor electrodes applications

In the present study, [Ni (4.5 nm)/Cu ( t Cu  = 2, 4 and 8 nm)] multilayers were pulse electrodeposited on stainless steel (AISI SS 304) substrate from sulphate based single bath technique. X-ray diffraction (XRD) was used to investigate the structure and stress of the Ni/Cu multilayer. The results from XRD analysis indicated that the deposited multilayers had a preferred crystal orientation of [111] and presence of satellite reflection suggested the formation of superlattice. The stress level within the deposited multilayers was found to be sensitive to the sublayer thickness. Sliding wear behaviour of electrodeposited Ni/Cu multilayer films has been investigated against a tungsten carbide (WC) ball as the counter body and compared with that of the constituents, Cu and Ni coatings. The wear tests were carried out by using a reciprocating ball-on-flat geometry at translation frequencies of 5 and 10 Hz, slip amplitude of 1 mm and at five different loads of 3, 5, 7, 9 and 11 N. Friction force was recorded on-line during the tests. At the end of the tests, the wear scars were examined by laser surface profilometry and scanning electron microscopy (SEM). Friction coefficient was found to be dependent on load and Cu layer thickness ( t Cu ) and the values for multilayers were border between Ni and Cu. Among multilayers, sample with minimum t Cu has shown the lowest friction coefficient and wear rate. With increasing t Cu , the wear mechanism changes from pure abrasive wear at t Cu =  2 nm, to particle entrapment at t Cu =  4 nm to particle embedding at t Cu =  8 nm. Detailed investigation of the wear scar morphology as well as wear rate measurement revealed that at low loads, ( H / E ) ratio and residual stress governed the wear rate and the principle wear mode was abrasive cutting. At intermediate loads, the role of residual stress became insignificant while wear was governed by ( H / E ) ratio and plastic deformation. However, at higher loads, plastic deformation played the major role.

Bibhu P. Swain

Papers

The analysis of carbon bonding environment in HWCVD deposited a-SiC:H films by XPS and Raman spectroscopy

Study of structural and electronic environments of hydrogenated amorphous silicon carbonitride (a-SiCN:H) films deposited by hot wire chemical vapor deposition

Electrochemical, bonding network and electrical properties of reduced graphene oxide-Fe2O3 nanocomposite for supercapacitor electrodes applications

Tribological behaviour and residual stress of electrodeposited Ni/Cu multilayer films on stainless steel substrate

Multiphase structure of hydrogen diluted a-SiC:H deposited by HWCVD