Photocatalytic heterogeneous organic transformation is considered as an efficient, clean atomic economy and low energy consumption strategy for organic synthesis. Conjugated polymers (CPs)-based ma...

Heterogeneous Photocatalytic Organic Transformation Reactions Using Conjugated Polymers-Based Materials

The photo-/electrocatalytic nitrogen reduction reaction (NRR) is an up and coming method for sustainable NH3 production; however, its practical application is impeded by poor Faradaic efficiency originating from the competing hydrogen evolution reaction (HER) and the inert N≡N triple bond activation. In this work, we put forth a method to boost NRR through construction of donor-acceptor couples of dual-metal sites. The synergistic effect of dual active sites can potentially break the metal-based activity benchmark toward efficient NRR. By systematically evaluating the stability, activity, and selectivity of 28 heteronuclear dual-atom catalysts (DACs) of M1M2/g-C3N4 candidates, FeMo/g-C3N4 is screened out as an effective electrocatalyst for NRR with a particularly low limiting potential of -0.23 V for NRR and a rather high potential of -0.79 V for HER. Meanwhile, TiMo/g-C3N4, NiMo/g-C3N4, and MoW/g-C3N4 with suitable band edge positions and visible light absorption can be applied to NRR as photocatalysts. The excellent catalytic activity is attributed to the tunable composition of metal dimers, which play an important role in modulating the binding strength of the target intermediates. This work may pave a new way for the rational design of heteronuclear DACs with high activity and stability for NRR, which may also apply to other reactions.

Highly Efficient Photo-/Electrocatalytic Reduction of Nitrogen into Ammonia by Dual-Metal Sites.

Recent developments in the use of metal oxides for photocatalytic degradation of pharmaceutical pollutants in water—a review

Among various kinds of photocatalytic semiconductors, graphitic carbon nitride (g-C3N4)-based photocatalysts have become the most attractive “celebrity” because of their stable chemical properties,...

Graphitic Carbon Nitride-Based Photocatalytic Materials: Preparation Strategy and Application

Alcohols (bioalcohols) is a class of chemicals that are used as a feedstock for the manufacturing of a large number of valuable intermediates in industrially important processes. Currently, sustainable technologies for selective conversion of alcohols utilize “green” oxidants, mainly, ambient air or oxygen. Due to the high affinity of oxygen towards silver, the latter serves as an active component of supported heterogeneous catalysts. In this review, we consider Ag-based catalysts that participate in gas- or liquid-phase oxidation of alcohols. Oxidation of methanol, ethanol, ethylene glycol, propylene glycol, glycerol, benzyl and allyl alcohols is mostly considered. A particular attention is paid to selective photooxidation of alcohols over Ag-based catalysts. We discuss the catalyst composition in terms of (1) the state of the active component, (2) the nature of the substrate, (3) support nature, and (4) the strength of the metal–support interactions.

Ag-Based Catalysts in Heterogeneous Selective Oxidation of Alcohols: A Review

In the present study, we report a novel nanocatalyst prepared by the modification of g-C3N4 nanosheets with a NiO/WO3 nanohybrid via a simple ultra-sonication method. A novel method was employed for the synthesis of the NiO/WO3 nanohybrid. The photocatalytic efficiency of the catalysts was explored in C–H activation and degradation of a product commonly found in pharmaceutical waste, namely metronidazole. The photocatalyst recorded a rapid and highly selective conversion of benzene to phenol under irradiation using a LED bulb. Degradation of metronidazole was carried out both in the presence of sunlight and LED light and monitored using UV-vis spectroscopy. It was observed that the degradation process was more efficient under solar light irradiation, where complete degradation was recorded in 90 minutes with a rate constant of 0.0165 min−1. The modified photocatalyst showed much higher efficiency when compared to the individual components of g-C3N4 and nanostructured NiO/WO3. The structural features of the photocatalyst were thoroughly investigated using powder XRD, SEM, TEM, XPS, UV-DRS, PL and BET analysis. This enhanced efficiency is attributed to a larger surface area, lower band gap and delayed recombination of photogenerated charge carriers at the heterojunction. The critical involvement of photoactive radicals in the degradation process was thoroughly investigated by trapping experiments using photoluminescence spectroscopy.

Fabrication of nanostructured NiO/WO3 with graphitic carbon nitride for visible light driven photocatalytic hydroxylation of benzene and metronidazole degradation

A Novel [Fe(acac)3] Interspersed g‐C3N4 Heterostructure for Environmentally Benign Visible‐Light‐Driven Oxidation of Alcohols

Mesoporous graphitic carbon nitride (g-C3N4) was modified with thermal grafting of Oryza sativa (rice) bran ash (OBA) and Triticum aestivum (wheat) bran ash (TBA). These novel catalysts were employed in transesterification reaction for upgrading triglycerides (TAG) of lipids into fatty acid methyl ester (FAME) with alcohol for biodiesel production at room temperature. The catalysts were systematically characterized with analytical techniques such as XRF, XRD, SEM, EDAS, TEM, TGA, XPS, BET and CO2-TPD. These basic green heterogeneous catalytic procedures exclude aqueous quenching, neutralization and saponification steps, tedious catalyst separation, and prevent corrosion in the reactor and engine. Introduction of otherwise decent transesterification catalysts OBA and TBA into graphitic carbon nitride nanosheets significantly enhances activity and reusability in the transesterification process. This increased activity of the nanostructured heterojunctions is attributed to the enhanced basicity, mesoporosity and surface area upon incorporation of OBA/TBA over graphitic carbon nitride nanosheets as confirmed by CO2-TPD and BET analysis. The obtained biodiesel samples were further characterized by 1H NMR and GC MS analysis. The biodiesel samples were tested for important physico-chemical properties to ensure their practical use.

Modified mesoporous graphitic carbon nitride: a novel high-performance heterogeneous base catalyst for transesterification reaction

Design of a Photoactive Bimetallic Cu‐Au@g‐C3N4 Catalyst for Visible Light Driven Hydroxylation of the Benzene Reaction through C–H Activation

Incorporation of nanosized ZnWO4 and Fe3O4 on graphitic carbon nitride to fabricate a novel, highly active magnetically recoverable catalyst in Claisen–Schmidt condensation

Meghali Devi

Papers

Fabrication of nanostructured NiO/WO3 with graphitic carbon nitride for visible light driven photocatalytic hydroxylation of benzene and metronidazole degradation

A Novel [Fe(acac)3] Interspersed g‐C3N4 Heterostructure for Environmentally Benign Visible‐Light‐Driven Oxidation of Alcohols

Modified mesoporous graphitic carbon nitride: a novel high-performance heterogeneous base catalyst for transesterification reaction

Design of a Photoactive Bimetallic Cu‐Au@g‐C3N4 Catalyst for Visible Light Driven Hydroxylation of the Benzene Reaction through C–H Activation

Incorporation of nanosized ZnWO4 and Fe3O4 on graphitic carbon nitride to fabricate a novel, highly active magnetically recoverable catalyst in Claisen–Schmidt condensation