Photocatalytic Oxygen Evolution from Functional Triazine‐Based Polymers with Tunable Band Structures

Abstract

Conjugated polymers (CPs) are emerging and appealing light harvesters for photocatalytic water splitting owingt ot heir adjustable band gap and facile processing. Herein, we report an advanced mild synthesis of three conjugated triazine-based polymers (CTPs) with different chain lengths by increasing the quantity of electron-donating benzyl units in the backbone.V arying the chain length of the CTPs modulates their electronic,optical, and redoxproperties, resulting in an enhanced performance for photocatalytic oxygen evolution, whichi st he more challenging half-reaction of water splitting owing to the sluggish reaction kinetics.O ur results could stimulate interest in these functional polymers where amolecular engineering strategy enables the production of suitable semiconductor redox energetics for oxygenic photosynthesis.

A Triazine‐Based Analogue of Graphyne: Scalable Synthesis and Applications in Photocatalytic Dye Degradation and Bacterial Inactivation

“…The solid-state 13 C-NMRs pectrum of TA-BGY showed the presence of sp-hybridized carbon of the triple bond (d = % 80 ppm) and sp 2 -hybridized carbon of the benzene unit (120-150ppm) and the triazine unit (d = % 170 ppm), similart o the reference compound (2,4,6-tris(phenylethynyl)-1,3,5-triazine) which showed corresponding signals at d = 80-100, 120-150, and 160-170 ppm, respectively (Figure 2A and Figure S5, SupportingI nformation). [8] In the FTIR spectrum (Figure 2B,C), the disappearance of the characteristicc arbonchloro bond of cyanuric chloride at 850 cm À1 as well as the terminal ethynyl carbon-protons tretchv ibration of 1,4-dithynylbenzene at 3277 cm À1 of the starting materials, togetherw ith the appearance of vibrationalb and of triazine unit at 1510 cm À1 (carbon-nitrogen stretching), benzene unit at 1360 cm À1 (benzene ring breathing), and carbon-carbon triple bond unit at 836 and approximately 2200 cm À1 (carboncarbon tripleb ond stretching), implied the formation of TA-BGY. [8][9] In the XPS spectrum of the TA-BGY (Figure 3), the emergence of the peaks with bindinge nergies of 398.8 (N 1s of the triazine ring), 284.3 (C 1s of benzene unit), 285.2 (C 1s of ethynyl unit) and 286.8 eV (C1s of triazine ring) provided additional evidenceo ft he formation of TA-BGY.M eanwhile, the ratio of C triazine :C phenyl :C ethynyl in the XPS spectrum of TA-BGY was 1:3.1:1.7, which was close to its theoretical value of 1:3:2( an infinitelye xtended two-dimensional TA-BGY plane).…”

“…[8] In the FTIR spectrum (Figure 2B,C), the disappearance of the characteristicc arbonchloro bond of cyanuric chloride at 850 cm À1 as well as the terminal ethynyl carbon-protons tretchv ibration of 1,4-dithynylbenzene at 3277 cm À1 of the starting materials, togetherw ith the appearance of vibrationalb and of triazine unit at 1510 cm À1 (carbon-nitrogen stretching), benzene unit at 1360 cm À1 (benzene ring breathing), and carbon-carbon triple bond unit at 836 and approximately 2200 cm À1 (carboncarbon tripleb ond stretching), implied the formation of TA-BGY. [8][9] In the XPS spectrum of the TA-BGY (Figure 3), the emergence of the peaks with bindinge nergies of 398.8 (N 1s of the triazine ring), 284.3 (C 1s of benzene unit), 285.2 (C 1s of ethynyl unit) and 286.8 eV (C1s of triazine ring) provided additional evidenceo ft he formation of TA-BGY.M eanwhile, the ratio of C triazine :C phenyl :C ethynyl in the XPS spectrum of TA-BGY was 1:3.1:1.7, which was close to its theoretical value of 1:3:2( an infinitelye xtended two-dimensional TA-BGY plane). [8] Scarcely any chloride peaks were found either in the surveys pectrum or in Cl 2p scan (Table S1, Supporting Information), indicating a complete substitution of chloro atoms in cyanuricc hloride by the 1,4-diethynylbenzenef unction.…”

“…[8][9] In the XPS spectrum of the TA-BGY (Figure 3), the emergence of the peaks with bindinge nergies of 398.8 (N 1s of the triazine ring), 284.3 (C 1s of benzene unit), 285.2 (C 1s of ethynyl unit) and 286.8 eV (C1s of triazine ring) provided additional evidenceo ft he formation of TA-BGY.M eanwhile, the ratio of C triazine :C phenyl :C ethynyl in the XPS spectrum of TA-BGY was 1:3.1:1.7, which was close to its theoretical value of 1:3:2( an infinitelye xtended two-dimensional TA-BGY plane). [8] Scarcely any chloride peaks were found either in the surveys pectrum or in Cl 2p scan (Table S1, Supporting Information), indicating a complete substitution of chloro atoms in cyanuricc hloride by the 1,4-diethynylbenzenef unction. [7] The O1 sp eaks found in Figure 1.…”

A Metal-Free Oxygenated Covalent Triazine 2-D Photocatalyst Works Effectively from the Ultraviolet to Near-Infrared Spectrum for Water Oxidation Apart from Water Reduction

“…3 μmol h –1 oxygen evolution rate under full arc irradiation. 26 Moreover, it is still challenging to demonstrate an organic photocatalyst possessing visible light activity of oxygen evolution comparable to the best inorganic oxygen evolution photocatalysts, for example, BiVO 4 . The present study employs an efficient strategy to enable the band gap narrowing primarily by shifting down the conduction band edge (CBE) of a wide band gap polymer photocatalyst by oxygenation, not only maintaining the strong oxidation potential but also enhancing visible light absorption to the NIR region; 27 as such it would be an ideal photocatalyst in a Z-Scheme system for complete water splitting.…”

Pyrene-based Conjugated Polymer/Bi₂MoO₆ Z-scheme Hybrids: Facile Construction and Sustainable Enhanced Photocatalytic Performance in Ciprofloxacin and Cr(VI) Removal under Visible Light Irradiation

“…Besides the traditional utilizations in light-driven organic synthesis and organic photovoltaics, CP have also revealed fantastic performances in photocatalysis, such as poly(diphenylbutadiyne) for pollutants degradation, polybenzothiadiazoles for H2 evolution and poly(dibenzo[b,d]thiophene 5,5-dioxide) for NO oxidation [20][21][22][23][24]. In addition, unlike the conventional semiconductors, its HOMO and LUMO potentials can be fine-tuned through varying the monomers or adjusting the molecular structures [25,26], implying that CP might be an ideal candidates for constructing Z-scheme hybrids, which has been confirmed by our previous studies. [27,28].…”