Synergetic effect in water treatment with mesoporous TiO₂/BDD hybrid electrode

Abstract

A mesoporous TiO2/BDD hybrid electrode showed a synergetic effect between electrochemical water treatment and photocatalytic water treatment.

Formation of ammonium ions by electrochemical oxidation of urea with a boron-doped diamond electrode

“…In our previous study, we demonstrated that oxidation ability was enhanced by using electrochemical treatment together with photocatalysis because electrochemically formed H 2 O 2 was reduced by electrons in the conduction band of TiO 2 to form OH . 5 The observed promotion of NO 2 À oxidation suggests that the photocatalyst also enhanced OH production in this study. Although the concentration of NO 3 À formed decreased (Fig.…”

“…Experiments were conducted with an H-type cell consisting of two glass cells, as described in our previous study. 5 One half cell contained the BDD working electrode and the other contained a Pt counter electrode. When the TiO 2 photocatalyst was used together with the BDD electrode, a Kr-Br excimer lamp producing 207 nm UV light (ORC Manufacturing Co., Ltd (Machida, Tokyo, Japan)) and mesoporous TiO 2 /BDD photocatalyst were included in the system.…”

Review on the Properties of Boron-Doped Diamond and One-Dimensional-Metal-Oxide Based P-N Heterojunction

“…The configuration of p-BDD and n-metal oxide has been most widely studied. In contrast to a continuous uniform film [ 26 , 27 , 32 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 ], the 1D nanostructure (e.g., NRs, NWs and NTs) that is free of defects, quantum-enhanced and has a large surface-area-to-volume ratio will not encounter the thermal mismatch with diamond, thereby substantially improving the performance of the hybrid structural heterojunction. For simplicity, we will focus on three different 1D n-type metal oxide (ZnO, TiO 2 and WO 3 )/p-BDD heterojunction structure types in this review in the following general examples.…”

“…They also used this hybrid electrode in water electrolysis to produce O 3 gas and other reactive oxygen species (ROS). In addition, ROS produced by electrochemistry were tested in water treatment under UV illumination and demonstrated the system’s suitability for advanced oxidation processes [ 27 ]. This simple water treatment system can be used to break down refractory organic matter in wastewater, a process that is still being studied.…”

“…This is because of the large surface-area-to-volume ratio, excellent charge carrier transport performance and good crystallization ability shown by these types of nanostructures [ 6 , 7 ]. Thus far, heterostructure optoelectronic devices have been formed by depositing n-type metal oxides on various p-type substrates, including Si [ 8 , 9 , 10 , 11 ], GaN [ 12 , 13 , 14 ], NiO [ 15 ], Cu 2 O [ 16 , 17 , 18 , 19 ], graphene [ 20 , 21 ], boron-doped diamond (BDD) film [ 22 , 23 , 24 , 25 , 26 , 27 ], and organic material [ 28 ]. Among them, BDD acts as an excellent p-type conductive material for high-temperature, high-power and radiation-proof photoelectronic devices with its large band gap at room temperature (5.47 eV) and high thermal conductivity [ 29 ].…”