SRM University

About: SRM University is a education organization based out in Chennai, India. It is known for research contribution in the topics: Computer science & Population. The organization has 10787 authors who have published 11704 publications receiving 103767 citations. The organization is also known as: Sri Ramaswamy Memorial University.

Doped h-BN monolayer as efficient noble metal-free catalysts for CO oxidation: the role of dopant and water in activity and catalytic de-poisoning

Abstract: Using a first principles approach, we investigated the catalytic activity of a noble metal-free n-doped (C → B, O → N) hexagonal boron nitride (h-BN) monolayer for CO oxidation. The CO adsorption ability and hence the preferred Eiley–Rideal (ER) and Langmuir–Hinshelwood (LH) mechanism for CO oxidation is dopant-dependent: CO is chemisorbed on O-doped h-BN (OBN) while it physically interacts with the C-doped h-BN (CBN) surface. Even though both C and O doping create similar donor states below the Fermi level (Ef), O doping results in a larger bond length of O–B1 (one of the nearest B atom), out-of-plane displacement of the B1 atom, and less positive charge on the B1 atom, synergistically contributing to higher atomic activity. The presence of a pre-adsorbed O2 molecule on both types of surfaces eliminates any chances of CO poisoning of the surface, and CO oxidation prefers to proceed via the ER mechanism with a small activation barrier. The high values of Sabatier activities suggest that the doped h-BN surface is superior to Au55and Pt55nanoclusters. In case of CO oxidation by means of the LH mechanism, a stable O2⋯CO intermediate is produced, which requires a high barrier energy to break the O–O bond. However, the presence of a H2O molecule increases the activity of the catalyst and helps in catalytic CO de-poisoning.

Enhanced osteoblast adhesion on polymeric nano-scaffolds for bone tissue engineering.

Abstract: Bone tissue engineering is an interdisciplinary field which is emerged for the development of viable substitutes that restore and maintain the function of human bone tissues. The success of bone tissue engineering depends on designing of the scaffolds. The polymer-based composite scaffolds containing micro- and nano-structures could provide a platform influencing osteoblastic cell adhesion, spreading, proliferation, and differentiation. Osteoblasts may adhere strongly to the nano-structures than micro-structures in the scaffolds due to the large surface area, better osteo-integrative property and mechanical reliability etc. In this review we are focusing the factors such as pore size, surface topography and roughness, protein adsorption and wettability of nano-structures and their interaction with cell surface integrins molecules. A better understanding of the interactions of nano-structures with osteoblastic cells will have potential applications in the regeneration of bone.