AgInS₂ and graphene co-sensitized TiO₂ photoanodes for photocathodic protection of Q235 carbon steel under visible light

Abstract

AgInS 2 nanoparticle and graphene nanosheet co-sensitized anatase TiO 2 nanotube array films were fabricated by a combination of hydrothermal reaction and electrochemical anodization on titanium sheets. The results showed that the co-sensitization of AgInS 2 nanoparticles and graphene nanosheets extended the photoresponse of TiO 2 nanotubes into the visible-light region, and improved the photogenerated charge separation and transfer capability. The photocurrent density of the AgInS 2 /graphene/TiO 2 composites (about 4.0 mA cm −2 ) was 20 times that of bare TiO 2 (only 0.2 mA cm −2 ) under visible-light illumination. The potential negative shift value of AgInS 2 /graphene/TiO 2 composites was up to 0.68 V versus saturated calomel electrode. The AgInS 2 /graphene/TiO 2 composites can provide Q235 carbon steel with highly efficient photocathodic protection under visible-light illumination.

Zn3In2S6/TiO2 Nanocomposites for Highly Efficient Photocathodic Protection to Carbon Steel

“…Since Na 2 S was a strong reducing agent which may reduce the photoanode, we selected the mixture of Na 2 S and NaOH as the hole scavenger. Furthermore, the addition of NaOH to Na 2 S solution could inhibit the hydrolysis of S. − A 300 W xenon lamp (PLS-SXE300D, AM 1.5G) was used as the light source with an intensity of 100 mW·cm –2 to simulate sunlight. All electrochemical tests in this work were performed using a CHI920D electrochemical workstation.…”

“…27 To achieve cathodic protection for carbon steel, the photogenerated electron energy of the PCP coating should be higher than the Fermi level of carbon steel. 28 Ren et al 27 have prepared a PPy/TiO 2 composite, which sensitizes TiO 2 and collects photogenerated electrons. Therefore, it provides PCP to carbon steel.…”

“…Compared with stainless steel, carbon steel is more sensitive to corrosion, the Fermi level of which is higher . To achieve cathodic protection for carbon steel, the photogenerated electron energy of the PCP coating should be higher than the Fermi level of carbon steel . Ren et al have prepared a PPy/TiO 2 composite, which sensitizes TiO 2 and collects photogenerated electrons.…”

Review on the Solar-Driven Photocathodic Protection of Metals in the Marine Environment

“…The bandgap difference between ZnIn 2 S 4 and rGO contributes to the establishment of a heterojunction electric field with TiO 2 facilitating efficient charge separation and transfer, and greatly improving the photo-electro-chemical activity of the composite material. Li et al [46] synthesized TiO 2 nanocomposites co-sensitized with AgInS 2 and graphene through a combination of hydrothermal reaction and electrochemical anodization. The photo-induced potential reduction of AgInS 2 /graphene/TiO 2 composite material can achieve 680 mV.…”

Preparation of Chitosan/Polyacrylamide/Graphene Oxide Composite Membranes and Study of Their Methylene Blue Adsorption Properties

“…The GO contains a large amount of oxygen-containing functional groups, i.e., epoxy, hydroxyl as well as carbonyl [ 9 ]. As a result, it will work well in many fields, such as DNA detection [ 10 ], cathodic protection [ 11 , 12 ], graphene transistors [ 13 ], and environmental protection, that can absorb the heavy metal ions and organic pollutants from polluted wastewater [ 14 , 15 ]. Lots of researchers have produced different GO-based materials as adsorbents for removing the heavy metal ions and organic dyes in the last few years.…”