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Carbon monoxide (CO) is shown to enhance the sensitivity of cancer cells to generate reactive oxygen species such as singlet oxygen ( 1 O 2 ) from chemotherapeutics and reduce the drug resistance. Herein, we introduced two Mn-based photoactivated CO releasing molecules conjugated with an emissive BODIPY (BDP) moiety with a general formula of Mn(CO) 3 (bpy-R-BDP)Br (R = H or I), labeled as Mn-bpy-H-BDP and Mn-bpy-I-BDP. While both complexes release CO with visible light, Mn-bpy-I-BDP releases CO and produces 1 O 2 from a single molecule. In addition to 1 O 2 generation, iodination of BDP red shifts the absorption of Mn-bpy-I-BDP further into the visible region and significantly increases the dark stability of the complex. Cyclic voltammetry and density functional theory (DFT) calculations suggest a Mn-based highest occupied molecular orbital (HOMO) and a BDP-based lowest unoccupied molecular orbital (LUMO) in these complexes. However, time-dependent DFT calculations suggest that the HOMO − 2(π BDP ) → LUMO(π BDP * ) is the main optical transition upon excitation with visible light in both complexes. The presence of a phosphorescence peak from the triplet excited state of bpy-I-BDP in both the free ligand and its Mn complex at 77 K was used as additional evidence for 1 O 2 production. We also probed formation of photo-intermediates and products during photolysis with Fourier-transform infrared, 1 H NMR, emission, and absorption experiments and DFT calculations.

Bi 2 WO 6 nanoplates were synthesized by a simple one-step hydrothermal method using oleic acid (OA) as a green and cheap capping agent. The X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) were used to characterize the products. The interaction between the precursor product and oleic acid was studied by Fourier Transform Infrared (FT-IR). In addition, the catalytic activity of prepared Bi 2 WO 6 for the oxidation of thiols to disulfides as an important reaction in both biological and chemical processes was investigated. It was found to be an efficient catalyst for the selective oxidation of thiols to the corresponding disulfides, without over-oxidation, at room temperature.

To design an efficient electrocatalyst for CO 2 reduction, a comprehensive understanding of the catalytic architecture and the reaction mechanism is required. Herein, we synthesized and analyzed a series of fac-[Re(bpy-X) (CO) 3 Cl] (abbreviated as Re I (bpy-X); bpy-X = 4,4′-disubstituted-2,2′bipyridine; X = t Bu, CH 3 , mesityl, H, phenyl, and methyl ester) catalysts for electrocatalytic CO 2 reduction with and without adding the cocatalyst [Zn(cyclam)] 2+ (cyclam = 1,4,6,11tetraazacyclotetradecane). Both computational and experimental results show that in the experiments bearing the [Zn(cyclam)] 2+ cocatalyst, the Re(I) catalysts require less energy input to reduce the CO 2 , indicating that the CO 2 -to-CO conversion occurs at a lower overpotential. Interestingly, in the Re(I) electrocatalyst bearing a strong electron-withdrawing group (methyl ester), [Zn(cyclam)] 2+ does not improve the CO 2 reduction activity. These results emphasize the importance of how the electronic distribution throughout the molecular architecture can enhance or suppress the nucleophilicity of Re I (bpy-X) electrocatalysts, even in the presence of a cocatalyst.