03098nas a2200277   4500008004100000022001400041245012600055210006900181260000900250300001200259490000600271520215500277653001902432653001902451653001902470653001402489653001202503100002302515700002102538700002902559700002902588700002402617700001902641700003002660856013002690       2023                        eng d  a2574-096200aFacile one-pot synthesis of Cu x O/TiO2 photocatalysts by regulating Cu oxidation state for efficient solar H2 production0 aFacile onepot synthesis of Cu x OTiO2 photocatalysts by regulati  cDEC   a104-1160 v73 a<p>
	Development of highly efficient CuxO/TiO2 photocatalysts by regulating the oxidation state of Cu exclusively in either single or mixed oxidation state(s) is desirable but difficult to achieve without employing any external reagents. The present work describes a one-pot synthesis strategy to obtain CuxO/TiO2 photocatalysts with Cu in +1 and/or +2 by using a suitable combination of ethylene diamine tetra acetic acid (EDTA) and ethylene diamine, carefully varying the Cu content, and heat treatment process. CuxO/TiO2 nanocomposite catalysts were characterized thoroughly by physicochemical methods. Textural analysis indicates a high dispersion of CuxO on porous TiO2 with p-n heterojunctions between them in CuxO/TiO2 catalysts. UV-visible spectral analysis suggests the presence of CuxO on TiO2 with significantly extended absorption from the UV to the visible region. X-ray photoelectron spectroscopy (XPS) analysis indicates a strong synergetic interaction between TiO2 and CuxO due to the comparable CB potential and p-n heterojunction at the interface among them. Photoelectrochemical studies demonstrate excellent charge-carrier separation efficiency, low charge-transfer resistance, and high double-layer capacitance with Cu2O/TiO2 photocatalysts. Photocatalytic efficacy of a CuxO/TiO2 nanocomposite in thin-film form has been demonstrated for solar hydrogen generation in sunlight. The incorporation of Cu+ in TiO2 largely improves the H-2 production, and all of the CuxO/TiO2 nanocomposites in thin-film form exhibited higher efficiency compared to their particulate/suspension counterpart. Among the composite catalysts, TiCu-1 in thin-film form, with Cu exclusively in +1 oxidation state, exhibited a high hydrogen production rate of 7.06 mmol/hg, which is 6 times higher than its suspension counterpart; also catalysts containing mixed Cu-oxidation states exhibited about 60-70% activity as that of TiCu-1. The superior performance of Cu2O/TiO2 nanocomposites in thin-film form was due to their enhanced light harvesting ability, high mass transfer rate, and easy accessibility of the reactant species to the active sites.</p>
10aheterojunction10aPhotocatalysis10aSolar hydrogen10athin film10atitania1 aRajendran, Sivaraj1 aMani, Sunesh, S.1 aNivedhitha, Thazhath, R.1 aAsoka, Anantha, Krishnan1 aArun, Pushkaran, S.1 aMathew, Thomas1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/facile-one-pot-synthesis-cu-x-otio2-photocatalysts-regulating-cu-oxidation-state-efficient02691nas a2200241   4500008004100000022001400041245015900055210006900214260000800283300001200291490000800303520180200311653003002113653001902143653001902162653003402181653001402215653001202229100002902241700003002270700002202300856012702322       2025                        eng d  a0360-319900aMultiphasic heterojunctions: a strategic approach to enhance the charge transfer dynamics of titania for superior solar photocatalytic hydrogen production0 aMultiphasic heterojunctions a strategic approach to enhance the   cMAR  a133-1460 v1133 a<p>
	Multiphasic titania has been prepared to study the role of multiple heterojunctions on the charge transfer dynamics and resultant photocatalytic hydrogen production. Through an acid regulated hydrothermal method, four materials with following phase compositions were prepared viz. single phase anatase and rutile, biphasic anatase-rutile and triphasic anatase-brookite-rutile. The phase compositions of the materials were confirmed through XRD and HRTEM studies. The biphasic and triphasic materials were found to be highly nanoparticulate in nature while forming numerous and diverse heterojunctions. In the triphasic material, various binary and ternary heterojunctions were observed. These heterojunctions performed in harmony to ensure efficient charge transport as shown by the low charge transfer resistance and high electron lifetime. This subsequently ensured a high reduction capability and photocurrent response. This all culminated into the triphasic material outperforming all other materials in solar photocatalytic hydrogen production. The H2 yield from the triphasic material was 81% and 40% higher than the pristine anatase and the biphasic material respectively. Additionally, by using the triphasic material in thin film form, a 4-fold increase in the hydrogen yield with a high apparent quantum efficiency of 8.2 % was achieved over the particulate form. The superior charge transport and photocurrent response due to the greater varied heterojunction formation in the anatase-rutile-brookite material as opposed to that in the biphasic material led to this superior performance. Thus, multiple heterojunctions, in this case, a triphasic heterojunction of anatase, rutile and brookite phases opens up a new avenue of research for efficient green hydrogen production.</p>
10aGreen hydrogen production10aheterojunction10aPhotocatalysis10aPhotoelectrochemical analysis10athin film10atitania1 aNingthoukhongjam, Pujita1 aGopinath, Chinnakonda, S.1 aNair, Ranjith, G.  uhttps://library.ncl.res.in/content/multiphasic-heterojunctions-strategic-approach-enhance-charge-transfer-dynamics-titania