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Summary: Conjugated monomer 2,6‐dimethylindole (DMI) was integrated into the triazine framework of polymeric carbon nitride (PCN) via molecular engineering. As‐prepared samples were utilized for photocatalytic evolution of hydrogen (H2) through water splitting and photodegradation of RhB dye under visible light. The integration of this monomer DMI has been dominated within the internal framework of PCN and operated as a substitution reaction membrane, retarding an appropriate control and promote the charge density in π‐electron conjugated system. It also promotes the charge transferring and separation to elevate the photocatalytic activity of PCN under visible light. The HER for pure PCN was found as 77.9 μmol/h, while for PCN‐DMI18.0 was predicted at 701.2 μmol/h, which is exclusively output approximately nine times higher than that of pure PCN respectively. Besides, the pseudo‐order kinetic constant of PCN‐DMI18.0 degradation of RhB was multiple times higher when contrasted to pristine PCN. [ABSTRACT FROM AUTHOR]

The systematic alteration of a carbon nitride unit (CNU) for visible light photocatalytic water splitting is a promising research subject owing to the increasingly serious energy and environmental complications. Herein, the conjugated monomer 3,6‐dibromopyridazine (DBP) is integrated within polymeric carbon nitride (PCN named as CNU = carbon nitride containing urea precursor) via thermal condensation, which is designated as CNU‐DBP. These samples are used for the first time in the photocatalytic conversion of CO2 reduction and hydrogen (H2) evolution through water splitting. Such integration intimidates the electron density, promoting charge transfer separation and elevating the photocatalytic activity of CNU under visible light illumination. The superior sample such as CNU‐DBP9.0 after 4 h of photooxidation generates 65.7 μmol of CO and 17.3 μmol of H2 of the reaction system, emphasizing the highest photocatalytic activity. The H2 evolution rate (HER) for pristine CNU is found as 11.9 μmol h−1, whereas for CNU‐DBP9.0 it is estimated at 178.2 μmol h−1 with 15 times greater activity. This process predicts a significant diversion in the specific area, bandgap, and chemical composition and promotes the efficient separation of photogenerated charge carriers from the ground state to the excited state of CNU, thereby considering it a best candidate for the photoreduction of CO2 source and water splitting into H2. [ABSTRACT FROM AUTHOR]

Summary: In recent 20 years, electronic equipment has been developing rapidly in the direction of light, miniaturization, flexibility, and integration. It is urgent to meet the needs of matching energy supply system to solve the practical application requirements in the fields of intelligent communication and mobile medical treatment. Electroactive polymers (EAPs) are recommendable material for manifesting muscle‐like actuation. The dielectric elastomers (DEs) obtained from the EAPs are quite capable of inducing electrical energy and transmute it into mechanical energy. DEs are capacitors covered by an outer elastic membrane, sandwiched between the two docile electrodes. In the beginning, for getting the efficient responses out of the DE actuators, the material requirements and electromechanical principal are applied. Viscoelastic damping, low dielectric loss, stretch ability, and dielectric permittivity are the desirable characteristics that we are expecting in a polymer. In the current research, we are going to adopt the sequential approach by describing the advances, challenges, and applications of DEAs in the coming future. [ABSTRACT FROM AUTHOR]

The modification of carbon nitride (CN) for visible light photocatalytic CO2 reduction is an important issue to explore in the context of energy and environmental challenges. The current work describes the fabrication of a butterfly-shaped photocatalyst derived from a heterojunction between the electron-rich organic monomer 2,5-dibromothiophene (TP) and a CN framework via copolymerization (UCN-TP). The successful incorporation of TP within CN means that it acts as a nucleophilic spare entity that provides electron solidity (π-conjugation) via charge allocation and increases the photocatalytic activity of CN (under visible light illumination). Density functional theory (DFT) data provide additional information on the amalgamation of TP inside CN and the reduced band gap. The best sample UCN-TP0.06 generated 68.18 μmole of CO and 18.52 μmole of H2 by photoreduction, demonstrating the highest photocatalytic activity. Moreover, this remarkable modification of the chemical configuration, band gap and surface area encouraged the good detachment of light-produced photons, thereby rendering it the best candidate for the photoreduction of CO2. [ABSTRACT FROM AUTHOR]

Reference 1 Hayat A., Sohail M., Taha T.A., Alenad A.M., Uddin I., Hayat A., Ali T., Shah R., Irfan A., Khan W.U. A superficial intramolecular alignment of carbon nitride through conjugated monomer for optimized photocatalytic CO2 reduction. However, the morphology did not sustain after adding the TDP monomer (change from nanosheets to irregular, rough surface nanoparticles). A Superficial Intramolecular Alignment of Carbon Nitride through Conjugated Monomer for Optimized Photocatalytic CO 2 Reduction. [Extracted from the article]

Correction for 'A butterfly shaped organic heterojunction photocatalyst for effective photocatalytic CO2 reduction' by Asif Hayat et al., CrystEngComm, 2021, 23, 4963–4974, https://doi.org/10.1039/D1CE00405K. [ABSTRACT FROM AUTHOR]

One of the most frequent ways to widen the adsorption range of carbon nitride (CN) is to add a well-known photosensitizer into its basic structure. So far, such attachments have been accomplished by using weak van der Waals forces. However, using strong covalent bonding to attach such photosensitizer with CN is yet to be determined. Here, for the first time, we covalently bonded porphyrin (5,10,15,20-tetrakis(4-(2,4-diamino-1,3,5-triazinyl) phenyl)-Porphyrin (TDP)), a renowned photosensitizer, effectively with CN by thermally balanced molecular strategy. A photoreaction system was set up for the deoxygenated conversion of CO2 to CO under visible light, where cobalt acted as a redox controller to speed up the charge transportation, while CN-TDP worked as a CO2 activating photocatalyst. The subsequent photocatalyst has a broader absorbance range, a greater specific surface area, and intramolecular organic connections that help to decrease the electron-hole pairs' recombination rate. Furthermore, the average weight ratio between urea and TDP was well-tuned, resulting in a fantastic CO2 photoconversion for CN-TDP7.0 compared to the blank sample. This substantial increase in photocatalytic activity predicts a significant shift in CN's specific surface area, band gap, chemical composition, and structure, as well as the efficient separation of photogenerated charge carriers from the ground state (HOMO) to the excited state (LUMO), making it a top candidate for CO2 photoreduction. At the same time, this approach paves the path for the bottom-up fabrication of carbon nitride nanosheets. [ABSTRACT FROM AUTHOR]