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The extensive use of single-atom catalysts (SACs) has appeared as a significant area of investigation in contemporary study. The single-atom catalyst, characterized by its maximum atomic proficiency and great discernment of the transition-metal center, has a unique combination of benefits from both heterogeneous and homogeneous catalysts. Consequently, it effectively bridges the gap between these two types of catalysts, leveraging their distinctive features. The utilization of SACs immobilized on graphene substrates has garnered considerable interest, primarily because of their capacity to facilitate selective and efficient photocatalytic processes. This review aims to comprehensively summarize the progress and potential uses of SACs made from graphene in photocatalytic carbon dioxide (CO2) reduction and hydrogen (H2) generation. The focus is on their contribution to converting solar energy into chemical energy. The present study represents the various preparation methods and characterization approaches of graphene-based single-atom photocatalyst This review investigates the detailed mechanisms underlying these photocatalytic processes and discusses recent studies that have demonstrated remarkable H2 production rates through various graphene-based single-atom photocatalysts. Additionally, the pivotal roleof theoretical simulations, likedensity functional theory (DFT), to understand the structural functional relationships of these SACs are discussed. The potential of graphene-based SACs to revolutionize solar-to-chemical energy conversion through photocatalytic CO2 reduction and H2 production is underscored, along with addressing challenges and outlining future directions for this developing area of study. By shedding light on the progress and potential of these catalysts, this review contributes to the collective pursuit of sustainable and efficient energy conversion strategies to mitigate the global climate crisis. [ABSTRACT FROM AUTHOR]

In this study, a plasmonic p–n heterojunction Ag@Ag2O–BiVO4 photocatalyst was successfully prepared by a simple chemical precipitation-reduction process. The obtained samples were tested by various measurements and the photocatalytic behavior in the decomposition of tetracycline (TC) under irradiation with visible light was studied. The photodegradation study exhibits that Ag@Ag2O–BiVO4 has the optimum activity and can efficiently degrade 83.52% of TC in 60 min by irradiation with visible light. Furthermore, the Ag@Ag2O–BiVO4 exhibited more pronounced visible light absorption and the best performances than the BiVO4 and Ag2O–BiVO4, which was mainly due to the LSPR of plasmonic Ag. The experimental radical trapping proved that the active species of the photocatalytic process act in the following order: ·O2− > h+ > ·OH. To find intermediates, the possible TC degradation pathways via HPLC–MS were also investigated. This research provides a successful method to develop a plasmonic photocatalyst with p–n heterojunction for wastewater treatment. [ABSTRACT FROM AUTHOR]

The feasibility of methods of trans-esterification reactions for the preparation of polyols from unsaturated soybean oil and castor oil have shown in this study. The polyol products formed from soybean oil has primary alcohol functional group. For castor oil polyol, hydroxyl group of any chain of triglyceride is replaced by chlorine. Thus the polyol formed has two hydroxyl (-OH) groups. Polyol is identified from hydroxyl functional group using Fourier Transform Infrared Spectroscopy (FTIR), and characterized by acid value. It is seen that the synthesized polyols are useful in the treatment of processes, using polyols for the production of polyurethanes, and also manipulated to synthesize polyurethane with required properties. [ABSTRACT FROM AUTHOR]

Iron oxides are considered promising electrode materials owing to their capability of lithium storage, but their poor conductivity and large volume expansion lead to unsatisfactory cycling stability. In this paper, an inexpensive, highly effective, and facile approach to the synthesis of Fe3O4 nanoparticles/reduced graphene oxide composite (Fe3O4/RGO) is designed. The synthesized Fe3O4/RGO composite exhibits high reversible capability and excellent cyclic capacity as an anode material in lithium-ion batteries (LIBs). A reversible capability of 701.8 mAh/g after 50 cycles at a current density of 200 mA·g−1 can be maintained. The synergetic effect of unique structure and high conductivity RGO promises a well soakage of electrolyte, high structure stability, leading to an excellent electrochemical performance. It is believed that the study will provide a feasible strategy to produce transition metal oxide/carbon composite electrodes with excellent electrochemical performance for LIBs. [ABSTRACT FROM AUTHOR]

Nonlinear optical (NLO) materials have several uses in many fields such as solid physics, biology, medicine, nuclear physics, and material research. Therefore, a series of nonfullerene-based derivatives ( CC10D1 - CC10D8 ) with a D-π-A configuration was planned for the NLO investigation using CC10R as the reference molecule with structural alternations at acceptor moieties. Natural bonding orbital (NBO), UV-vis spectra, frontier molecular orbitals (FMOs), global reactivity parameters (GRPs), transition density matrix (TDM), and density of states (DOS) were analyzed using the M06/6-311G(d,p) functional in chloroform solvent to understand the NLO responses of CC10R and CC10D1 - CC10D8 . The highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) band gaps of CC10D1 - CC10D6 were illustrated to be lower than that of CC10R , with the larger bathochromic shift (726.408-782.674 nm) resulting in a significant NLO response. Along with the band gap, the FMO method also identified an efficient interfacial charge transfer from D to A moieties via a π-bridge, which was further supported by the DOS and TDM map. Moreover, NBO calculations demonstrated that extended hyperconjugation and strong internal molecular interactions were important in their stabilization. The dipole moment (μ), linear polarizability ⟨α⟩, hyperpolarizability (β total ), and second-order hyperpolarizability (γ total. ) were studied for CC10R and CC10D1 - CC10D8 . Among all of the derivatives, CC10D2 was proven to be the most appropriate candidate because of its suitable NLO behavior such as being well-supported by a reduced band gap (2.093 eV) and having a suitable maximum absorption wavelength (782.674 nm). Therefore, CC10D2 was reported to have a greater value of first hyperpolarizability (208 659.330 a.u.) compared with other derivatives and CC10R . For the second hyperpolarizability, a greater value was obtained for CC10R (5.855 × 10 7 a.u.), and its derivatives showed results comparable to that of the parent chromophore for γ total . This theoretical framework reveals that structural customization with different acceptor units plays a significant role in obtaining attractive NLO materials for optoelectronic applications., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)