Elucidation of the unsymmetrical effect on the piezoelectric and semiconducting properties of Cd-doped 1D-ZnO nanorods

Abstract

The unsymmetrical effect of piezoelectric and semiconducting properties of Cd-doped 1D-ZnO NRs is presented.

Regulation of Charge Carrier Dynamics in ZnO Microarchitecture‐Based UV/Visible Photodetector via Photonic‐Strain Induced Effects

“…The Raman peak located at 108 cm −1 is assigned to E 2 (low) phonon mode. The additional Raman peaks located at about 342, 391, 446, and 589 cm −1 are assigned to E 2H – E 2L , A 1 transverse optical (TO), E 2 (high), and E 1 longitudinally optical (LO) secondary multiphoton scattering modes, respectively . Generally, E 1 (LO) represents the defect sites containing zinc interstitial (Zn i ) and oxygen vacancy (V O ) in ZnO.…”

“…Figure a shows the I–V characteristics of the ZnO MW in the dark and under illumination at different light intensities of 6, 11, and 17 mW cm −2 . The photocurrent response ( I Ph ) increased from 1.64 µA (dark current, I D ) to 9.04 µA (6 mW cm −2 ), 12.67 µA (11 mW cm −2 ), and further to 13.83 µA (17 mW cm −2 ) at an applied biasing voltage of ±8 V. The working of PD depends on the mechanism where the sensing material (ZnO) generates charge carriers (e − and h + ) upon adsorbing the incident photon energy (hv) . The photogenerated charge carriers tunnel through the Schottky barrier (SB) contacts formed at M–S interfaces contributing to the photocurrent ( I Ph ) of the device.…”

“…The time response parameters (τ R , τ D ) were calculated by estimating the exponential rise to 63% (≈1 − e −1 ) of I Ph and exponential decay to 37% (≈e −1 ) of I Ph. Also, Figure e illustrates the switching behavior of ZnO F‐MW‐based PD with a rise time (τ R ) of ≈4 s and decay time (τ D ) of ≈5 s. Besides, the characteristics parameter of PDs was calculated such as responsivity ( R 405 nm ), photoconductive gain ( G ), detectivity ( D *) and are summarized in Table 1 . The as‐fabricated ZnO microarchitecture‐based PD exhibits comparable performance to that of earlier reports as shown in Table S1 in the Supporting Information.…”

“…Latterly, the photocurrent responsivity, gain factor, and broadband wavelengths of ZnO PDs were improved drastically by various ways such as: (i) growth of novel pure nanostructures of ZnO (3D branched type, comb, and crown capped), (ii) foreign elements doping into ZnO nanostructures, and (iii) core–shell type organic/inorganic hybrid structures, respectively. Till now, sodium (Na), gallium (Ga), cadmium (Cd), lithium (Li), cobalt (Co), and gold (Au) elements were substituted into ZnO to improve the photonic properties. Similarly, many organic polymers along with ZnO structure were investigated such as poly(3,4‐ethyleneioxythiophene):polystyrenesulfonate, poly(3hexylthiophene) (P3HT), polyaniline, and poly[2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylenevinylene] to enhance the photosensitivity.…”

Quantitative characterization of the long-term charge storage of a ZnO-based nanorod array film through persistent photoconductance

“…The peaks at 1044.66 eV and 1021.57 eV corresponding to the Zn-2p 3/2 and 2p 1/2 core levels indicate the presence of Zn 2+ . [22][23][24] An attempt to separate the O 1s spectra into several subspectral components was made (shown in the ESI †), centred at 529.97 AE 0.04 eV (Oa), 530.4 AE 0.3 eV (Ob), 531.37 AE 0.3 eV (Oc), and 532.30 AE 0.25 eV (Oe), respectively. The low binding energy components located at Oa and Ob are attributed to the O 2À ions on the lattices surrounded by copper atoms and zinc atoms with a full supplement of nearest-neighbour O 2À ions separately; Oc is assigned to the O 2À ions in the oxygen decient regions of ZnO and CuO; the Oe peak of the O 1s spectrum is related to the absorption of a specic species, such as adsorbed O 2 or adsorbed H 2 O, -CO 3 .…”