Polycrystalline samples of Cs1.17In0.81Cl3 were prepared by annealing a mixture of CsCl, InCl, and InCl3, stoichiometric for the targeted CsInCl3. Synchrotron powder X-ray diffraction refinement and chemical analysis by energy dispersive X-ray indicated that Cs1.17In0.81Cl3, a tetragonal distorted perovskite derivative (I4/m), is the thermodynamically stable product. The refined unit cell parameters and space group were confirmed by electron diffraction. In the tetragonal structure, In+ and In3+ are located in four different crystallographic sites, consistent with their corresponding bond lengths. In1, In2, and In3 are octahedrally coordinated, whereas In4 is at the center of a pentagonal bipyramid of Cl because of the noncooperative octahedral tilting of In4Cl6. The charged-ordered In+ and In3+ were also confirmed by X-ray absorption and Raman spectroscopy. Cs1.17In0.81Cl3 is the first example of an inorganic halide double perovskite derivative with charged-ordered In+ and In3+. Band structure and optical conductivity calculations were carried out with both generalized gradient approximation (GGA) and modified Becke–Johnson (mBJ) approach; the GGA calculations estimated the band gap and optical band gap to be 2.27 eV and 2.4 eV, respectively. The large and indirect band gap suggests that Cs1.17In0.81Cl3 is not a good candidate for photovoltaic application.

Layered Li-rich/Mn-rich NMC (LMR-NMC) is characterized by high initial specific capacities of more than 250 mAh/g, lower cost due to a lower Co content and higher thermal stability than LiCoO2....

In this work, the effects of Si‐doping in Cu2ZnSnS4 are examined computationally and experimentally. The density functional theory calculations show that an increasing concentration of Si (from x = 0 to x = 1) yields a band gap rise due to shifting of the conduction band minimum towards higher energy states in the Cu2Zn(Sn1−xSix)S4. CZTSiS thin film prepared by co‐sputtering process shows Cu2Zn(Sn1−xSix)S4 (Si‐rich) and Cu2ZnSnS4 (S‐rich) kesterite phases on the surface and in the bulk of the sample, respectively. A significant change in surface electronic properties is observed in CZTSiS thin film. Si‐doping in CZTS inverts the band bending at grain‐boundaries from downward to upward and the Fermi level of CZTSiS shifts upward. Further, the coating of the CdS and ZnO layer improves the photocurrent to ≈5.57 mA cm−2 at −0.41 VRHE in the CZTSiS/CdS/ZnO sample, which is 2.39 times higher than that of pure CZTS. The flat band potential increases from CZTS ≈0.43 VRHE to CZTSiS/CdS/ZnO ≈1.31 VRHE indicating the faster carrier separation process at the electrode–electrolyte interface in the latter sample. CdS/ZnO layers over CZTSiS significantly reduce the charge transfer resistance at the semiconductor–electrolyte interface.

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The progress of the topochemical reduction reaction that converts LaSrNiRuO 6 into LaSrNiRuO 4 depends on the synthesis conditions used to prepare the oxidized phase. Samples of LaSrNiRuO 6 that have been quenched from high temperature can be readily and rapidly converted into LaSrNiR-uO 4 . In contrast, samples that have been slow-cooled cannot be completely reduced. This reactivity difference is attributed to the differing microstructures of the quenched and slow-cooled samples, with the former having much smaller average crystalline domain sizes and larger lattice strains than the latter. A mechanism to explain this effect is presented, in which the greater "plasticity" of small crystalline domains helps lower the activation energy of the reduction reaction. In addition, we propose that the enhanced lattice strain in quenched samples also acts to destabilize the host phase, further enhancing reactivity. These observations suggest that the microstructure of a material can be used to "activate" topochemical reactions in the solid state, expanding the scope of phases that can be prepared by this type of reaction.