Semiconducting Conjugated Microporous Polymer: An Electrode Material for Photoelectrochemical Water Splitting and Oxygen Reduction

Abstract

Intriguing structural design and inherent nanoporosity of conjugated microporous polymers (CMP) with extended π‐conjugation have stimulated research interest in exploring their applications to solve challenging environmental and energy problems. However, only few attempts are made so far to identify the semiconducting properties of these CMP networks having direct relevance to energy conversion, electronic devices and photocatalysis. The present study identifies the semiconducting properties of a conjugated microporous polymer, namely, poly(1,3,5‐triethynylbenzene) (PTEB) in detail using photoluminescence, UV‐Visible absorption, Kelvin probe force microscopy, cyclic voltammetry, Mott‐Schottky analysis and photoelectrochemical studies. Integration of heteroatoms such as nitrogen into the polymer network by post‐thermal treatment is shown to enhance significantly the activities towards oxygen reduction reaction. A drastic improvement in the activity of PTEB observed on nitrogen incorporation into the carbon skeleton is attributed to an increase in the number of electrochemical active sites and increase in its pore size. The systematic evaluation of conducting properties of CMP materials promises future development of electronic, electrochemical and photoelectrochemical devices.

Conjugated Porous Polymers: Ground‐Breaking Materials for Solar Energy Conversion

“…The first reported work we found using a CPP as a photoelectrode was reported by Jayanthi et al in 2017, focusing on the investigation of the semiconducting properties of poly(1,3,5triethynylbenzene) (PTEB). [166] To prepare the photoelectrodes, the polymer was synthesized in the presence of CuI as bulk polymer and then was deposited into ITO. They studied the photoluminescence and UV-vis absorption, and characterize the photoelectrodes through Kelvin probe force microscopy, cyclic voltammetry, and Mott-Schottky analysis.…”

“…c) Photocurrents recorded in aqueous electrolyte (0.1 m KOH solution) at a scan rate of 5 mV s −1. Adapted with permission [166]. Copyright 2017, Wiley.…”

Metal-Free Pyrene-Based Conjugated Microporous Polymer Catalyst Bearing N- and S-Sites for Photoelectrochemical Oxygen Evolution Reaction

“…Due to the wide scopes in bandgap tenability, surface functionalization, and structural sustainability, CMPs are being considered as a very useful class of efficient electro/photo-electrocatalysts (Zhang et al, 2019;Taylor et al, 2020). However, only a few CMPs have been studied as photoelectrocatalytic OER catalysts so far (Jayanthi et al, 2017). Heteroatoms like N, S, B, P, and Si, entrenched in carbon sheets, modify the electronic structure of the carbon frameworks by tailoring the Fermi energy levels and tuning the local electronegativity.…”

Electron Donor and Acceptor Influence on the Nonlinear Optical Response of Diacetylene-Functionalized Organic Materials (DFOMs): Density Functional Theory Calculations

“…The design of high performance NLO materials involves appropriate donor-π-conjugated bridge-acceptor (D-π-A) systems that can be tailored through structural modification of the π-conjugated bridge, D or A substituents [8,9,10,11,12,13,14,15,16,17]. Materials having diacetylene complexes have attracted much interest in photocatalysis, optics, electronics, photo and thermochromism [18,19,20]. Therefore polymers and small molecules having diacetylene moieties in their backbone have been widely explored [21].…”