**1. Introduction**

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[29] A. Khan, S. Marupaduga, M. Alam, N. J. Ekins-Daukes, Appl. Phys. Lett. 85, 5218

[30] A. Khan, A. Freundlich J. Gou, A. Gapud, M. Imazumi, and M.Yamaguchi, "Self-an‐ nihilation of electron-irradiation-induced defects in InAsXP1-X/InP multiquantum-well

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solar cells," *Applied Physics Letters*, vol. 90, p. 233111, 2007.

Village, Waikoloa, Hawaii, May 7-12, 2006, p. 1763.

Appl. Phys. 89, 4263 (2001).

(2004).

222 Solar Cells - New Approaches and Reviews

The most of modern commercial optoelectronic devices such as Laser diodes, solar cells, lightemitting diodes (LEDs), and nonlinear optical devices are built on the basis of traditional inorganic semiconductors. However, a lot of progress has been made in producing devices based on organic electronic materials, in recent decades [1], but the current development prospects of organic materials are mostly limited in their scope to relatively low-performance areas. Low mobility of charge carriers in molecular materials, can be mentioned as one of import reason for this topic. Strong chemical interaction between organic molecules and metal electrodes can destroy the injection of charge carriers into the organic molecules [2].

A qualitatively different way of using organic electronic compounds can be *via* exploiting resonant interactions in organic-inorganic hybrid structures [3–5]. Within the same hybrid structure, one could combine high conductivity of the inorganic semiconductor component with the strong light-matter interaction of the organic component. However, this properties classified them as named organic-inorganic hybrid materials with large exciton binding energy (about several hundreds of meV) because of large dielectric confinement. These layered organic-inorganic perovskites with the general formula (RNH3)2MX4 (R= CnH2n+1; M= Pb or Sn; X= halogen), can be regarded as semiconductor/insulator multiple quantum well systems consisting of lead halide semiconductor layers sandwiched between organic ammonium insulator layers [6–10]. Lead halide is well known as typical ionic crystals with a large exciton binding energy (a few tens of meV) [11]. Further, the organic layer has a larger band gap and lower dielectric constant than those of the inorganic layer. Therefore, the exciton binding energy is considerably amplified due to the quantum and dielectric confinement effects [12]. As a result, stable excitons are observed even at room temperature. Thus, the appropriate properties of both the organic and the inorganic materials can exploited to overcome their

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limitations when used separately. The lead halide based organic-inorganic perovskites have potential applications in nonlinear optical devices [13,14] and novel luminescent devices [15,16]. Organometallic halide perovskites have recently emerged as a promising material for high-efficiency nanostructured devices [17]. Over the past several months, we have witnessed an unanticipated breakthrough and rapid progress in the field of developing photovoltaics, with the realization of highly efficient solar cells based on organometallic trihalide perovskite absorbers [18–21].

Simplified schematic representation of the crystal structure of the organic-inorganic hybrids as shown in Figure 1. The two-dimensional inorganic layers and an organic ammonium layer are stacked alternately. These layers is comprised of a two-dimensional sheet of [MX6 -4] octahedra which are connected at the four corners with halide ions on the plane.

**Figure 1.** Schematic structure of the organic-inorganic hybrid crystal

As shown in Figure 2, the six halogen ions X surrounded M2+, forming an octahedral [MX6 -4] cluster. The inorganic layer has thickness of a few atomic layers. The –NH3 <sup>+</sup> ends of the cations bind to the anion layers of [MX6 -4] in a specific orientation determined by hydrogen bonding with both equatorial and axial halide ions. A multi-layer structure is organized by neutralizing [MX6 -4] with alkylammonium ions [24].

Also Perovskites Material use as solar cell in last few years as show in Figure 3. The reasons for make them as one of best candidate for photovoltaics is explain below:


**Figure 2.** Schematic of the cluster structure of the organic-inorganic hybrid []

limitations when used separately. The lead halide based organic-inorganic perovskites have potential applications in nonlinear optical devices [13,14] and novel luminescent devices [15,16]. Organometallic halide perovskites have recently emerged as a promising material for high-efficiency nanostructured devices [17]. Over the past several months, we have witnessed an unanticipated breakthrough and rapid progress in the field of developing photovoltaics, with the realization of highly efficient solar cells based on organometallic trihalide perovskite

Simplified schematic representation of the crystal structure of the organic-inorganic hybrids as shown in Figure 1. The two-dimensional inorganic layers and an organic ammonium layer are stacked alternately. These layers is comprised of a two-dimensional sheet of [MX6

surrounded M2+, forming an octahedral [MX6


octahedra which are connected at the four corners with halide ions on the plane.

**Figure 1.** Schematic structure of the organic-inorganic hybrid crystal

cluster. The inorganic layer has thickness of a few atomic layers. The –NH3

for make them as one of best candidate for photovoltaics is explain below:

**5.** Stability for maintain more than 80% of its initial efficiency after 500 hours.

**6.** Lower manufacturing costs because of directly deposition from solution

**1.** Appropriate Material properties of high efficiency photovoltaics

with both equatorial and axial halide ions. A multi-layer structure is organized by neutralizing

Also Perovskites Material use as solar cell in last few years as show in Figure 3. The reasons

As shown in Figure 2, the six halogen ions X-


**2.** High coefficient of optical absorption

**3.** Excellent charge carrier transportation

**4.** Promising device parameters

bind to the anion layers of [MX6

[MX6



<sup>+</sup> ends of the cations

absorbers [18–21].

224 Solar Cells - New Approaches and Reviews

**Figure 3.** Best research cell efficiencies of all type of solar cells (NREL)
