154056 nm) EDX and TEM images were obtained using a HR-TEM (Fei

154056 nm). EDX and TEM images were obtained using a HR-TEM (Fei Technai G2 F20 S Twin microscope) operated at 300 keV. Results and discussion TEM images of PANI-powdered GaSe samples are presented in Figure 1. Expanded images (Figure 1a,b) demonstrate

the presence (simultaneously with ultralarge microcrystals) of two types of nano-objects: thin stripes (up to few nanometers in height and up to 100 nm in length) and discs with rather broad diameter distribution (see Figure 1f). Beside the majority of particles are located inside 5 to 15 nm size region (mean size was estimated as 9.2 nm with 5.2 nm value of standard deviation), there are also several Selleck CHIR98014 ultrasmall (less than 5 nm) and ultralarge (>20

nm) objects. The stripes and discs underwent atomic resolution on HR-TEM (Figure 1c,d,e), which magnifies boxed areas on Figure 1a,b. As shown by HRTEM (Figure 1c,d), the heights of such stripes consist of GaSe elementary sandwiches, packed along с crystallographic axis. It should be noted that there is an essential broadening of lattice plane spacing in this direction, yielding 0.833 nm (this value does not vary for many nanocrystals from different sample areas). Comparing with the same value for bulk GaSe material (0.796 nm for (0002) planes spacing), the c lattice parameter increased by about 4.4%. Some of the nanocrystals are so well resolved in order to obtain even fringes from higher (0004) planes with the same value of increasing c lattice parameter. Lenvatinib The elementary tetralayers of GaSe structure along (11–20) direction Fenbendazole are somehow bended by selleck products mechanical stresses, applied normally to above-mentioned direction on the whole particles (Figure 1c,d), but we did not observe any extended defects or

elementary tetralayer fractures. The number of such monolayer (ML) per particles could vary from 10 to 20 (5 to 10 lattice parameters). The smaller particles (1 to 2 ML) during the interaction with electron beam, collinear to edges in plate-like particle geometry, simply do not effectively scatter electrons to make them visible by TEM, but were detected by optical measurements earlier [18] and as thin lattice resolved discs on Figure 1a,e. That is easily proved by comparing contrast of 10 and 15 to 17 ML particles in corresponding TEM images. The nature of disc-like particles is elucidated through analyzing Figure 1e. They are the same particles in Figure 1c,d, but their face plane oriented normally to the electron beam. We can also observe lattice fringed on one well oriented plane in respect to the electron beam. This time, the lattice spacing yields 0.969 nm, coinciding exactly with triple value of (10–10) lattice plane.

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