Each month, the ISGS Newsletter features an interesting and striking micrograph (or series of micrographs) chosen from a recent issue of the Journal of Sol-Gel Science and Technology or from unpublished sources such as PhD theses, etc (with full attribution given). If you know of any interesting images that might be suitable, please contact the ISGS Newsletter Editor for inclusion. The micrographs can be optical, SEM, TEM, AFM, etc, and a brief description of the samples should be provided.
The first series is taken from the work of Ma, Liu, Du, Ge and Sun entitled “Pt nanoparticles anchored on bifunc-tional CuFe2O4 submicrospheres with improved catalytic properties for the reduction of [Fe(CN)6]3− by S2O32−” (JSST, (2022); https://doi.org/10.1007/s10971-022-05963-1). This work explores the synthesis of catalyti-cally active spherical CuFe2O4 cores with diameters of 200-300 nm, and the subsequent deposition of Pt nano-particles to form core-shell CuFe2O4@Pt nanocomposite catalysts. Their results demonstrate that the intrinsic catalytic properties of the CuFe2O4 cores with respect to the reduction of [Fe(CN)6]3- to [Fe(CN)6]4- are significantly enhanced by the homogeneous dispersion of Pt nanoparticles immobilised on the surface of the cores.
The second series of micrographs is from the work of Deepthi, Sebastian and Vidhya. This paper, entitled “Influence of GO content on ZnO: GO composite thin films for visible light driven photocatalytic degradation of model pollutants” (JSST, (2022); https://doi.org/10.1007/s10971-022-05976-w), investigates the effect of gra-phene oxide (GO) content on the photocatalytic activity of ZnO:GO films for the decomposition of organics such as methylene blue and phenol. The resulting spin-coated films have an intriguing ripple-structured morphology, which is modulated by varying the GO content from 0 to 20 % (Images b (0 %); c (5 %); d (10 %); and e (20 %). The nanostructure varied across multiple photocatalytic cycles (compare image (d) (10 % GO,0 cycles); and im-age (f) (10 % GO, 5 cycles), although only minor reductions in the corresponding photocatalytic activity were ob-served. The film containing 10 % GO was found to be more efficient than the undoped ZnO by 89 % and 74 % for the degradation of methylene blue and phenol, respectively.
The third series of images is from the work of Yang, Pan, Fang, Su and Cheng entitled “Fabrication of Ce doped CoIn2S4 microspheres as effi-cient photocatalyst for degradation of rhodamine B” (JSST, (2022) 104, 380- 386; https://doi.org/10.1007/s10971- 022-05945-3). This paper explores the fabrication and characterisation of striking flowerlike particles composed of nanosized sheets doped with vary-ing Ce content (image (a), CoIn2S2; images (b, c, d), Ce/CoIn2S2 with 5, 10 or 20 % Ce, respectively). Doping was found to enhance the photocatalytic activity of the nanomaterial, with the optimum performance obtained with 10 % doping.
The final series of images is from the work of Kazi, Tigote, Gaikwad, Kamble, Bhale, Shringare, Musrif and Inam-dar. This paper, entitled “Effect of embedding aluminium and yttrium on the magneto-optic properties of lantha-num spinel ferrite nanoparticles synthesised for photocatalytic degradation of methyl red” ((JSST, (2022) 104, 354-364; https://doi.org/10.1007/s10971-022-05848-3), describes the synthesis of a series of substituted ferrites with stoichiometry La1-xAlxYyFe2-yO4 and their photocatalytic activity for the decomposition of methyl red. The po-rous microstructure and crystallite size of the materials are modulated by the values of x and y, for x=y=0.25, 0.5 and 0.75 (Figures A, B, and C, respectively). The magnetic properties (magnetization, hysteresis and coercivity) are also controlled by the extent of doping. The highest photocatalytic activity for the degradation of methyl red was observed for x=y=0.75.