Study of charge transport in P3HT:SiNW-based photovoltaic devices

Abstract

Hybrid devices based on silicon nanowires (SiNWs) dispersed in a conjugated polymer poly(3-hexylthiophene) P3HT thin films have been realized. The carrier transport mechanism in inorganic/organic hybrid nancocomposites consisting of SiNW dispersed in P3HT layer was investigated by using I -V characteristics and impedance spectroscopy measurements. The conduction mechanism in these hybrid nanocomposites has been identified to be thermionic emission at the interfaces. The electrical parameters of the structure have been investigated by modelization of the I -V characteristics using an electrical equivalent circuit and have been extracted for the different SiNW volume ratios. The barrier height, the series resistance and the shunt resistance values of the diodes have been calculated as about 0.9 eV, several k and several M , respectively. The diode behaves as non-ideal one because of the series resistance and the Donor/Acceptor interface layer. The impedance spectroscopy study, in the frequency range 100 Hz-100 kHz, shows a typical behavior of disordered materials and indicative of a hopping transport in the investigated temperature

Investigation of structural, optical and electrical properties of a new cobalt phthalocyanine thin films with potential applications in perchlorate sensor

“…Organic materials have recently attracted a great interest as semi conducting materials [1,2] and have been successfully incorporated into solar cells [3] and chemical sensors [4]. Metallo-phthalocyanines and their polymers gained importance because of their unique photoconducting and semiconducting properties [5].…”

A Theoretical Study on the Operation Principle of Hybrid Solar Cells

“…P3HT is a wide band gap polymer and is the most popular and studied donor material used in organic photovoltaics [25,26] and SiNWs ensure large donor-acceptor intefacial area with continous interpenetrating pathways for better charge transport to the electrodes [27]. The input parameters for calculations are as follows: axs = 4.35 nm and axt = 0.32 nm, Z = 77 for Iridium, ε = 7, μx = 1.99 × 10 −26 kg, = 0.06 eV, = 0.76 eV [4], Rda = 0.05 nm, Rf = 8 nm, τ = 2230 ps [28], L = 0.11 nm, Rd = 1 nm [29] = −3.03 eV, = −4.00 eV [30]. Using the above design and parameters, the various rates are calculated as shown in Table 1.…”

“…[30], where the choice is based on the following experimental conditions: The HOMO of P3HT should be positioned above the valence band (VB) of SiNW to inject holes into the hole transport layer and hence into the anode and at the same time it should also accept holes generated by light absorption in the SiNW. The LUMO of P3HT should be located above the CB of SiNW so that electron collection can occur efficiently at the silicon interface and electrons generated in the nanowires can be collected at the cathode [30].…”

Performance Enhancement of Bulk Heterojunction Hybrid Solar Cell Using Macroporous Silicon

“…The diode factor as calculated from the ln(J)-V characteristic (Figure 9) of macro-PSi fabricated by 15 min etching was found to be 4.36. This very high value of diode ideality factor (4.36) indicates strong recombination at the heterojunction interface resulting from the barrier inhomogeneity, series resistance, image force lowering, existence of interfacial layers, recombination effect of charge-carrier drift and diffusion or tunneling currents through the barrier or a combination of these effects [30].…”