This paper is one of a series exploring simple approaches for the estimation of lattice energy of ionic materials, avoiding elaborate computation. The readily accessible, frequently reported, and easily measurable (requiring only small quantities of inorganic material) property of density, rho(m), is related, as a rectilinear function of the form (rho(m)/M(m))(1/3), to the lattice energy U(POT) of ionic materials, where M(m) is the chemical formula mass. Dependence on the cube root is particularly advantageous because this considerably lowers the effects of any experimental errors in the density measurement used. The relationship that is developed arises from the dependence (previously reported in Jenkins, H. D. B.; Roobottom, H. K.; Passmore, J.; Glasser, L. Inorg. Chem. 1999, 38, 3609) of lattice energy on the inverse cube root of the molar volume. These latest equations have the form U(POT)/kJ mol(-1) = gamma(rho(m)/M(m))(1/3) + delta, where for the simpler salts (i.e., U(POT)/kJ mol(-1) < 5000 kJ mol(-1)), gamma and delta are coefficients dependent upon the stoichiometry of the inorganic material, and for materials for which U(POT)/kJ mol(-1) > 5000, gamma/kJ mol(-1) cm = 10(-7) AI(2IN(A))(1/3) and delta/kJ mol(-1) = 0 where A is the general electrostatic conversion factor (A = 121.4 kJ mol(-1)), I is the ionic strength = 1/2 the sum of n(i)z(i)(2), and N(A) is Avogadro's constant.
The
role of interface contact between two oxides, CeO2 and
TiO2, for the photocatalytic elimination of toluene is
examined in a series of samples with variable quantities of ceria.
Samples having ceria contents in the 1 to 10 mol % range improve significantly,
exhibiting up to 3.5 times the activity of the bare nano-TiO2 catalyst. To interpret the photocatalytic behavior, this contribution
develops a novel spectro-kinetic approach where a joined analysis
of the kinetics of the reaction and the fate of charge charriers is
merged with the mathematical modeling of the light–catalyst
interaction at the photoreactor. This produces a self-consistent approach
that simultaneously validates the kinetic model and interprets the
activity on rigorous bases. The study is completed with a multitechnique
examination of the solids using X-ray diffraction and electron paramagnetic
resonance, UV–vis, and X-ray photoelectron spectroscopies as
well as high-resolution transmission electron microscopy. The results
provide quantitative evidence that the oxide–oxide contact
controls the photoactivity through the number of hole-related species
available at the surface of the composite materials and that this
number is in turn related to the stabilization of reduced Ce species
present at the Ce–Ti interface.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.