TiO2-NT electrodes modified with Ag and diamond like carbon (DLC) for hydrogen production by alkaline water electrolysis


Baran E., Baz Z., ESEN R., Devrim B. Y.

APPLIED SURFACE SCIENCE, vol.420, pp.416-428, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 420
  • Publication Date: 2017
  • Doi Number: 10.1016/j.apsusc.2017.05.180
  • Journal Name: APPLIED SURFACE SCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.416-428
  • Çukurova University Affiliated: Yes

Abstract

In present work, the two-step anodization technique was applied for synthesis of TiO2 nanotube (NT). Silver and diamond like carbon (DLC) were coated on the surface of as prepared TiO2-NT using chemical reduction method and MW ECR plasma system. The morphology, composition and structure of the electrodes were examined by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The results showed that Ag nanoparticles, having size in the range of 48-115 nm, are evenly distributed on the top, inside and outside surface of TiO2-NT and when DLC was coated on the surface of TiO2-NT and TiO2-NT-Ag, the top of nanotubes were partially open and the pore diameter of hexagonal structure decreased from 165 nm to of 38-80 nm. On the other hand, the microhardness test and contact angle measurements revealed that additions of Ag and diamond like carbon have a positive effect on the mechanical properties of TiO2-NT film. The electro-catalytic properties of the electrodes towards the hydrogen evolution reaction (HER) were investigated by the electrochemical measurements recorded in 1 M KOH solution. In addition, long-term durability of electrodes towards HER and the energy consumption of alkaline electrolysis were investigated. The energy requirement showed that while the deposition of silver provides approximately 14.95% savings of the energy consumption, the DLC coating causes increase in energy consumption. (C) 2017 Elsevier B.V. All rights reserved.