Direct coating of a g-C₃N₄ layer onto one-dimensional TiO₂ nanocluster/nanorod films for photoactive applications

Abstract

We report the coating of metal-free graphitic carbon nitride (g-C3N4) onto titanium dioxide (TiO2) nanorods via a thermal evaporation method. Prior to g-C3N4 coating, TiO2 nanoclusters were grown on TiO2 nanorods to enhance the surface area by dipping in a TiCl3 solution for 12, 24 and 36 h. The prepared films were analyzed to assess the improvement in absorbance and reduction in recombination losses. Nanoclustered TiO2 grown for 24 h and then coated with a g-C3N4 film (i.e., TC_24h_CN) had the highest photocurrent of 235 and 290 μA, respectively, when measured by transient photocurrent and linear sweep voltammetry techniques. The enhanced performance resulted from a reduced recombination of electron-hole pairs. The TC_24h_CN film displayed an excellent photoresponse over 15 h of exposure to visible light and hence could potentially be used in water purification device technology.

Influence of C3N4 Precursors on Photoelectrochemical Behavior of TiO2/C3N4 Photoanode for Solar Water Oxidation

“…The investigation by Yang et al shows IPCE extended to visible region as in the absorption edge of C3N4 decorated TiO2 red shifted compared to that of TiO2 [28]. Similar trends were noticed with several TiO2/C3N4 systems [29,30].…”

“…Based on the aforementioned discussion and the previous reports, plausible mechanism has been depicted in Figure 7 [29][30][31]33]. The band diagram of TiO 2 and C 3 N 4 heterojunction can be envisaged as displayed in Figure 7.…”

“…The obtained IPCE spectra are in consistent with the absorption spectra of TiO2/C3N4-T, TiO2/C3N4-CM, TiO2/C3N4-CMT and TiO2 where TiO2/C3N4 photoanodes exhibit slight decrease in the band gap (Figure 5b). The enhanced IPCE for TiO2/C3N4-CMT could be due to improved charge separation at the interface as TiO2 forms staggered band alignment with C3N4 [29][30][31].…”

Carbon Nitride Materials for Water Splitting Photoelectrochemical Cells

“…Thei nsitu methods can be further divided into gas-phase and liquid-phase.O ne of the first successful depositions was accomplished by ag as-phase method:c hemical vapor deposition (CVD). [52] Additional gas-phase physical or chemical methods are known, for example,t hermal vapor condensation (TVC,s ometimes referred to as thermal evaporation), [53][54][55][56] plasma-based Menny Shalom received his PhD from Bar Ilan University,I srael, where he studied the operation mechanism of quantum-dot-sensitized solar cells including their synthesis and design. Forh is postdoc he joined the group of Prof. Markus Antonietti at Max Planck Institute of Colloids and Interfaces (MPI), Germany,a saMinerva fellowship fellow.I n 2013 he was appointed as ag roup leader at the MPI.…”

Kohlenstoffnitridmaterialien für photochemische Zellen zur Wasserspaltung

“…Eine der ersten erfolgreichen Abscheidungen erfolgte durch ein Gasphasenverfahren:d ie chemische Gasphasenabscheidung (CVD). [52] Weitere physikalische oder chemische Gasphasenverfahren sind bekannt, beispielsweise thermische Gasphasenabscheidung (TVC,g elegentlich auch als thermische Verdampfung bezeichnet), [53][54][55][56] plasmabasierte CVD-Varianten, [37,57] gepulste Laserabscheidung [58] und magnetgefiltertes Lichtbogen-Ionenplattieren im Va kuum. [59] Die Flüssigphasen-Alternative beinhaltet Polymerisation und Kondensation auf der Oberfläche des leitfähigen Substrats.…”