A p‐p⁺ Homojunction‐Enhanced Hole Transfer in Inverted Planar Perovskite Solar Cells

Abstract

Perovskite solar cells (PSCs) have triggered a research trend in solar energy devices in view of their high power conversion efficiency and ease of fabrication. However, more delicate strategies are still required to suppress carrier recombination at charge transfer interfaces, which is the necessary path to high‐efficiency solar cells. Here, a p–p+ homojunction was constructed on basis of NiO film to enhance hole transfer in an inverted planar perovskite solar cell. The homojunction was generated by fabricating a NiO/Cu:NiO bilayer film. The density functional theory calculation demonstrated the charge density difference in the two layers, which could generate a space charge region and a band bending at the junction, and the result was further proved by energy level structure analysis of NiO and Cu:NiO films. The designed homojunction could accelerate the hole transfer and inhibit carrier recombination at the interface between hole transfer layer and perovskite layer. Finally, the inverted planar perovskite solar cell with p–p+ homojunction showed an efficiency of 18.30 % and a high fill factor of 0.81, which were much higher than the counterpart of the PSCs individually using NiO or Cu:NiO as hole transfer layer. This work developed a new structure of hole transport layer to enhance the performance of PSCs, and also provided new ideas for design of charge transfer films.

Stability of perovskite solar cells: issues and prospects

“…With a strong working stability and a PCE of 18.3%, the PSC with bilayer HTM maintained 80% or so after 350 hours. 22 Min et al recently fabricated PSCs with highest PCE of 25.8% using inter-layer modification which reduce the interface defects between the SnO 2 ETL and perovskite absorber layer. 23 The devices maintained almost 90% of their initial efficiency after 500 hours of continuous light exposure.…”

Large-scale preparation of CsPbBr3 perovskite quantum dot/EVA composite adhesive film by melting for crystal silicon solar cell

“…Recently, perovskite quantum dots (PQDs) [13][14][15][16] have become a research hotspot and have potential application prospects in photoelectric devices such as LED [17][18][19], transistor [20] and solar cell [21][22][23][24]. CsPbX 3 PQDs have the advantages of high quantum yield, high stability, low cost synthesis method and controllable high intensity luminescence [25][26][27][28], and have been successfully used as downshifting materials for CSSCs.…”

Dynamic covalent polymer engineering for stable and self-healing perovskite solar cells

“…In order to promote the commercialization of perovskite solar cells (PSCs), numerous research groups are committed to achieving devices with outstanding power conversion efficiency (PCE) and long-term stability. [1][2][3][4][5][6][7][8][9] Inverted (p-i-n) perovskite solar cells have become a hot research field due to their unique interface structure which brings better long-term stability. Recently the certified PCE of p-i-n PSC has reached 25.39% through the efforts of research communities.…”