Metal-organic frameworks built from [Fe 3 (μ 3-O)(COO) 6 ] clusters and fumaric acid ligand, the so-called MIL-88 A(Fe) is a wellknown environment-friendly promising material for many applications. In this paper, three different morphologies of MIL-88 A(Fe) such as rod, diamond and spindle have been synthesized separately by reacting FeCl 3 * 6H 2 O and fumaric acid in 1 : 1 metal-ligand stoichiometric ratio using two different solvents such as water and DMF via hydrothermal method. The morphology of the products and their particle sizes were obtained using SEM and three distinct morphologies viz., rod, diamond and spindle were clearly distinguished by TEM. All the three samples were characterized by FT-IR, PXRD, UVDRS, PL, XPS and BET, and the effect of the morphologies of MIL-88 A (Fe) on the photocatalytic degradation of Rhodamine B (RhB) was studied under sunlight. The addition of an H 2 O 2 electron acceptor can markedly enhance the photocatalytic Rhodamine B degradation of MIL-88 A(Fe). Among these three, rod-shaped morphology of MIL-88 A(Fe) shows the higher photocatalytic effect for the degradation of Rhodamine B under sunlight due to its lower band gap, high surface area, and lower electronhole recombination rate which enable them the transfer of electrons for the photocatalytic degradation. We found that 98% degradation of RhB in 50 min has taken place by using r-MIL-88 A(Fe) as the catalyst under sunlight.

We have demonstrated the photocatalytic efficiency of the Ag/AgCl@MIL-88A(Fe) composite for the degradation of organic dyes and p-nitrophenol in water.

Reduced graphene oxide supporting plasmonic photocatalyst (Ag) on ZnO has been synthesized via a facile two-step microwave synthesis using RGO/ZnO and AgNO. First step involves fabrication of RGO/ZnO via microwave irradiation. The nanocomposites were characterized by X-ray diffraction analysis, transmission electron microscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. Ag/RGO/ZnO shows enhanced photoactivity under visible light for the degradation of Rhodamine B. Enhanced charge separation and migration have been assigned using UV-vis diffuse reflectance spectra, photoluminescence spectra, electrochemical impedance spectra, and TCSPC analysis. The improved photoactivity of Ag/RGO/ZnO can be ascribed to the prolonged lifetime of photogenerated electron-hole pairs and effective interfacial hybridization between RGO and Ag with ZnO nanoparticles. Ag nanoparticles can absorb visible light via surface plasmon resonance to enhance photocatalytic activity.

2D/1D heterojunction α-Fe2O3/C3N4 photocatalysts containing α-Fe2O3 microrods and polymeric carbon nitride flakes are synthesised through the calcination of Fe-based metal-organic frameworks and boost the visible light photocatalytic degradation of rhodamine B.

Solar photocatalytic technology based on semiconducting materials has gained the attention of the scientific community to solve the energy crisis and environmental remediation. Zeolitic imidazolate frameworks (ZIFs) are a subfamily of metal–organic frameworks (MOFs) with the isomorphic topologies of zeolites and coordinative compositions of MOFs. Owing to high specific surface areas, tunable channels and high thermal stabilities, zeolitic imidazolate frameworks (ZIFs) have been used in catalytic applications. In this paper, ZIF-8 was used as a matrix to synthesize 0D/2D heterojunction photocatalysts, viz., ZnO/C3N4-x% (x = 2.5, 5 and 10), for the photocatalytic degradation study of rhodamine B (RhB). The synthesized composite materials were characterized using FTIR, PXRD, UVDRS, PL, TEM, and BET analyses. TEM images showed the nearby contacts between ZnO and C3N4 in the hybrid and the uniform distribution of ZnO on the surface of the C3N4 nanosheet, thus increasing the development of 0D/2D heterojunction. The hybrid system ZnO/C3N4-5% (ZCN-5) showed good photocatalytic activity for the degradation of RhB under sunlight. A possible mechanism for the improved photocatalytic activity of the ZnO/C3N4 composite is also suggested. This exploratory study demonstrates the effective separation and migration of photo-induced electron–hole pairs between the 2D C3N4 sheet and 0D ZnO for the improved performance of heterojunction photocatalysts.