We discovered that perovskite (Ba,La)SnO 3 can have excellent carrier mobility even though its band gap is large. The Hall mobility of Ba 0.98 La 0.02 SnO 3 crystals with the n-type carrier concentration of ∼8-10×10 19 cm -3 is found to be ∼103 cm 2 V -1 s -1 at room temperature, and the precise measurement of the band gap Δ of a BaSnO 3 crystal shows Δ=4.05 eV, which is significantly larger than those of other transparent conductive oxides. The high mobility with a wide band gap indicates that (Ba,La)SnO 3 is a promising candidate for transparent conductor applications and also epitaxial all-perovskite multilayer devices. a) Author to whom correspondence should be addressed. Electronic mail: sangc@physics.rutgers.edu 2 Transparent conducting oxides (TCOs), exhibiting the contraindicative properties of optical transparency in the visible region and high DC electrical conductivity, are widely utilized as optical window electrodes in photovoltaic devices, liquid crystal displays and solar energy conversion devices. [1][2][3] There have been significant attempts to find alternative TCO materials to replace indium tin oxide due to its soaring price, and new TCOs such as doped ZnO and SnO 2 have been, in fact, already utilized. On the other hand, most of TCOs that have been investigated so far are associated with band gaps significantly less than 4 eV, so they do not transmit ultraviolet (UV) light.For example, the band gaps of SrTiO 3 (STO), ZnO, In 2 O 3 , and SnO 2 are 3.25, 3.3, 2.9, and 3.6 eV, respectively. 4-7 Thus, the discovery of TCOs with band gaps > 3.6 eV is central to enhance the efficiency of, for example, solar energy harvesting.Furthermore, the epitaxial all-perovskite multilayer heterostructures based on STO have recently attracted much attention due to the multiplicity of advantageous physical properties of perovskites. These all-perovskite multilayer heterostructures have great potentials for innovative micro-and nanoelectronic devices. 8,9 However, the mobility of doped STO is low at room temperature (RT) (~11 cm 2 V -1 s -1 ), 10 and the instability of oxygen content in doped oxides such as oxygen-deficient STO is often a detrimental issue inducing fatigue and degradation. 11 Therefore, the critical matter of the development of all-perovskite multilayer devices is finding new perovskite materials exhibiting high carrier mobility near RT and good oxygen stability.Herein, we report that La-doped perovskite BaSnO 3 (BSO) exhibits high carrier mobility with a large band gap, and thus is a promising candidate for transparent conductor applications with possible use in epitaxial all-perovskite multilayer devices.Alkaline earth stannates, with the formula of ASnO 3 (A=Ca, Sr and Ba), are widely used in the electronic industry for their optimal dielectric and gas-sensing properties. 12-14 BSO has an ideal cubic perovskite structure, and is an insulator with a valence band derived from orbitals of π-symmetry (mainly of oxygen 2p-character) and a conduction band with dominant Sn 5s-character. 15 T...

Li(3)V(2)(PO(4))(3)/graphene nanocomposites have been firstly formed on reduced graphene sheets as cathode material for lithium batteries. The nanocomposites synthesized by the sol-gel process exhibit excellent high-rate and cycling stability performance, owing to the nanoparticles connected with a current collector through the conducting graphene network.

1D nanowires of all-inorganic lead halide perovskites represent a good architecture for the development of polarization-sensitive optoelectronic devices due to their high absorption efficient, emission yield, and dielectric constants. However, among as-fabricated perovskite nanowires with the lateral dimensions of hundreds nanometers so far, the optical anisotropy is hindered and rarely explored owing to the invalidating of electrostatic dielectric mismatch in the physical dimensions. Here, well-aligned CsPbBr and CsPbCl nanowires with thickness T down to 15 and 7 nm, respectively, are synthesized using a vapor phase van der Waals epitaxial method. Strong emission anisotropy with polarization ratio up to ≈0.78 is demonstrated in the nanowires with T < 40 nm due to the electrostatic dielectric confinement. With the increasing of thickness, the polarization ratio remarkably reduces monotonously to ≈0.17 until T ≈140 nm; and further oscillates in a small amplitude owing to the wave characteristic of light. These findings not only represent a demonstration of perovskite-based polarization-sensitive light sources, but also advance fundamental understanding of their polarization properties of perovskite nanowires.

Dislocations are mobile at low temperatures in surprisingly many ceramics but sintering minimizes their densities. Enabling local plasticity by engineering a high dislocation density is a way to combat short cracks and toughen ceramics.