Chemical binding

About: Chemical binding is a research topic. Over the lifetime, 1822 publications have been published within this topic receiving 52516 citations.

Functionalization of semiconductor surfaces

Abstract: Chapter 1. Introduction Franklin (Feng) Tao, Yuan Zhu, and Steven L. Bernasek Chapter 2. Surface Analytical Techniques Ying Wei Cai and Steven L. Bernasek Chapter 3. Structures of Semiconductor Surfaces and Origins of Surface Reactivity with Organic Molecules Yongquan Qu and Keli Han Chapter 4. Pericyclic Reactions of Organic Molecules at Semiconductor Surfaces Keith T. Wong and Stacey F. Bent Chapter 5. Chemical Binding of Five-membered and Six-membered Aromatic Molecules Franklin F. Tao and Steven L. Bernasek Chapter 6. Influence of Functional Groups in Substituted Aromatic Molecules on the Selection of Reaction Channel in Semiconductor Surface Functionalization Andrew V. Teplyakov Chapter 7. Covalent Binding of Polycyclic Aromatic Hydrocarbon Systems Dr. Yong Kian Soon and Professor Xu Guo-Qin Chapter 8. Young Hwan Min, Hangil Lee, Do Hwan Kim, and Sehun Kim Chapter 9. Ab initio molecular dynamics studies of conjugated dienes on semiconductor surfaces Mark E. Tuckerman and Yanli Zhang Chapter 10. Formation of Organic Nanostructures on Semiconductor Surfaces Zakir Hossian and Maki Kawai Chapter 11. Formation of Organic Monolayers through Wet Chemistry Damien Aureau and Yves J. Chabal Chapter 12. Chemical Stability of Organic Monolayers Formed in Solution Leslie E. O Leary, Erik Johansson, and Nathan S. Lewis Chapter 13. Immobilization of Biomolecules at Semiconductor Interfaces Robert J. Hamers Chapter 14. Perspective and Challenge Franklin (Feng) Tao and Steven L. Bernasek

Catalysis by Confinement: Enthalpic Stabilization of NO Oxidation Transition States by Micropororous and Mesoporous Siliceous Materials

Abstract: Mesoporous silica and purely siliceous zeolites with voids of molecular dimensions (MFI, CHA, BEA) catalyze NO oxidation by O2 at near ambient temperatures (263–473 K) with reaction orders in NO and O2 identical to those for homogeneous routes and with negative apparent activation energies. These findings reflect the stabilization of termolecular transition states by physisorption on surfaces or by confinement within voids in processes mediated by van der Waals forces and without the involvement of specific binding sites. Such interactions lead to the enthalpic stabilization of transition states relative to the gaseous reactants; such enthalpic benefits compensate concomitant entropy losses upon confinement because of the preeminent role of enthalpy in Gibbs free energies at low temperatures. These data and their mechanistic interpretation provide clear evidence for the mediation of molecular transformations by confinement without specific chemical binding at active sites.

Facile synthesis of Ti4O7 on hollow carbon spheres with enhanced polysulfide binding for high-performance lithium–sulfur batteries

Abstract: As the next generation of electrochemical energy storage devices, lithium sulfur (Li–S) batteries have many advantages such as high theoretical specific capacity (1675 mAh g−1) and energy density (2600 kw h kg−1), non-toxicity and low cost. However, the poor electrical conductivity of sulfur cathodes and the shuttling effect of lithium polysulfides during cycling strongly hinder the commercial application of Li–S batteries. In this study, Magneli phase Ti4O7 nanoparticles were successfully prepared on the surface of hollow carbon spheres (HCS) through a carbothermal reduction reaction. The synthesized HCS@Ti4O7 with a mesoporous structure exhibited a uniform spherical morphology with a large specific surface area (512 m2 g−1) and the pore volume of 0.58 cm3 g−1. The introduction of a polydopamine (PDA) layer during the preparation was confirmed to effectively inhibit the grain coarsening of Ti4O7. Moreover, the high content of sulfur loading (70%) did not affect the morphology of HCS@Ti4O7, which suggested its stable architecture. The assembled coin cells exhibited the superior reversible capacity of 1427 mAh g−1 at 0.1C and favorable cycling stability from 1168 mAh g−1 to 601 mAh g−1 after 800 cycles at 0.5C with the capacity decay rate of only 0.06% per cycle. This excellent performance and stability were attributed to the strong chemical binding effects of Ti4O7 on lithium polysulfides and the stable morphology maintenance during cycling. This study provides a novel conception to design and synthesize nanocomposites between reduced metal oxides and carbon with uniform and stable mesoporous structures for high-performance Li–S batteries.