Synthesis and electrical and optoelectronic properties of poly[(N‐benzyldiphenylamino)methane]

Abstract

Poly[(N‐benzyldiphenylamino)methane] was synthesized by the condensation polymerization of benzyldiphenylamine and formalin (30% HCOH in water) and examined for electrical and optoelectronic properties. Dark conductivity and photoconductivity of the polymer film were investigated by steady‐state measurements. Current‐voltage characteristics and intrinsic photoconduction of the polymer in the visible wavelength range were studied. A superlinear current increase is tentatively explained in the light of the Poole‐Frenkel effect. Dielectric constant and dielectric loss parameters of the polymer are independent of frequency (50 Hz–10 kHz) and temperature (273–323 K), respectively. The growth and decay rates of the photocurrent depend on the applied voltage, and the photocurrent varies directly with the light intensity. The activation energies for dark conductivity and photoconductivity are 1.16 eV and 1.05 eV, respectively, and the optical energy band gap as evaluated from absorption coefficient spectra is 2.86 eV.

Electron spin resonance and optical studies of poly(methylmethacrylate) doped with CuCl2

“…The second one has a valley behavior with minimum value at W = 7.5%. These changes were argued by Akhter et al20 as first order process (carrier generation and recombination); or they may be due to some modifications in the size of the amorphous domains or platelets.…”

“…For optical transitions caused by photons of energy h ν > E opt , the density of both conduction and valence extended electronics states is assumed to depend on the square root of the energy, as found in a Fremi free‐electron gas,18–20 leading to an absorption coefficient, α, which depends on the photon energy as where $ \sqrt{B} $ is a proportional constant also known Tauc's constant and E opt is defined as the energy band gap between the valence band and conduction band.…”

“…For optical transitions caused by photons of energy hm > E opt , the density of both conduction and valence extended electronics states is assumed to depend on the square root of the energy, as found in a Fremi free-electron gas, [18][19][20] leading to an absorption coefficient, a, which depends on the photon energy as…”