01936nas a2200193   4500008004100000022001400041245013200055210006900187260011000256300001400366490000600380520111600386100001801502700002001520700002001540700002401560700002901584856012901613       2011                        eng d  a1754-569200aShape preserving chemical transformation of ZnO mesostructures into anatase TiO2 mesostructures for optoelectronic applications0 aShape preserving chemical transformation of ZnO mesostructures i  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAUG  a2835-28390 v43 a<p>In this work we report on the synthesis of various ZnO mesostructures (rods, spheres, flakes and flower-like morphologies) by hydrothermal and co-precipitation methods and their remarkable and complete transformation into anatase TiO2 mesostructures with nominally similar shapes using controlled low temperature TiCl4 treatment. Various techniques are used to demonstrate the phase purity and morphology details. Based on the careful examination of the transformation of ZnO rods into TiO2 tubes we suggest a mechanism which embodies initial formation of a thin TiO2 shell on the ZnO surface by ion exchange (Ti4+-Zn2+) followed by Zn diffusion through the shell and its oxidation on the surface. We used these converted TiO2 mesostructures for light harvesting in Dye Sensitized Solar Cells (DSSCs) to enhance the conversion efficiency. It is shown that DSSCs made using a doctor bladed film of TiO2 nanoparticles with an overlayer of TiCl4 treated ZnO flowers yield a solar cell efficiency of 6.9% which is considerably higher than that with only TiO2 nanoparticle film (5.4%) of comparable thickness.</p>1 aMuduli, Subas1 aGame, Onkar, S.1 aDhas, Vivek, V.1 aYengantiwar, Ashish1 aOgale, Satishchandra, B.  uhttps://library.ncl.res.in/content/shape-preserving-chemical-transformation-zno-mesostructures-anatase-tio2-mesostructures-001555nas a2200229   4500008004100000022001400041245007200055210006700127260011000194300001400304490000600318520071600324100002001040700002101060700002001081700002401101700002401125700002001149700002401169700002901193856010301222       2011                        eng d  a2040-336400aStrong photo-response in a flip-chip nanowire p-Cu2O/n-ZnO junction0 aStrong photoresponse in a flipchip nanowire pCu2OnZnO junction  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcOCT  a4706-47120 v33 a<p>Cu2O nanoneedles are synthesized on a copper substrate by a simple anodization and reducing ambient annealing protocol. ZnO nanorods are grown on ITO coated glass by a low temperature chemical route. The electronic and photo-response properties of the p-Cu2O/n-ZnO flip-chip heterojunction are then studied and analyzed. We show that the I-V characteristic is rectifying and the junction exhibits a good photoresponse (similar to 120% under 1 V reverse bias) under AM 1.5 (1 Sun) illumination. This nano-heterojunction photo-response is far stronger as compared to that of a pulsed laser deposited thin film p-Cu2O/n-ZnO heterojunction, which can be attributed to higher junction area in the former case.</p>1 aDeo, Meenal, S.1 aMujawar, Sarfraj1 aGame, Onkar, S.1 aYengantiwar, Ashish1 aBanpurkar, Arun, G.1 aKulkarni, Sneha1 aJog, Jyoti, Prakash1 aOgale, Satishchandra, B.  uhttps://library.ncl.res.in/content/strong-photo-response-flip-chip-nanowire-p-cu2on-zno-junction-0