Ultrathin Perovskite Monocrystals Boost the Solar Cell Performance

Abstract

Grains and grain boundaries play key roles in determining halide perovskite‐based optoelectronic device performance. Halide perovskite monocrystalline solids with large grains, smaller grain boundaries, and uniform surface morphology improve charge transfer and collection, suppress recombination loss, and thus are highly favorable for developing efficient solar cells. To date, strategies of synthesizing high‐quality thin monocrystals (TMCs) for solar cell applications are still limited. Here, by combining the antisolvent vapor‐assisted crystallization and space‐confinement strategies, high‐quality millimeter sized TMCs of methylammonium lead iodide (MAPbI3) perovskites with controlled thickness from tens of nanometers to several micrometers have been fabricated. The solar cells based on these MAPbI3 TMCs show power conversion efficiency (PCE) of 20.1% which is significantly improved compared to their polycrystalline counterparts (PCE) of 17.3%. The MAPbI3 TMCs show large grain size, uniform surface morphology, high hole mobility (up to 142 cm2 V−1 s−1), as well as low trap (defect) densities. These properties suggest that TMCs can effectively suppress the radiative and nonradiative recombination loss, thus provide a promising way for maximizing the efficiency of perovskite solar cells.

Autonomous Reconstitution of Fractured Hybrid Perovskite Single Crystals

“…By using optimized fabrication methods, HOIP crystals can now be manufactured with excellent bulk optoelectronic features, low density of defects, extended absorption windows, low charge-trap density, high charge carrier mobility, long carrier diffusion length, and long carrier lifetimes. [9][10][11][12][13][14][15][16] While successfully employed as high-energy radiation and visible-light detectors, single crystals have not been applied as a viable substitute to polycrystalline HOIPs in other key optoelectronic applications, such as LEDs and photovoltaics yet, [17][18][19] and the lack of mechanical robustness and compliance required for prolonged operation is usually cited as one of their greatest impediments. [19] Indeed, the pronounced brittleness, fragility, and proneness to wear of HOIP crystals currently hamper their implementation into devices.…”

Numerical investigation of graphene and 2D‐MoS 2 facilitated perovskite/silicon “p‐i‐n” structure for solar cell application

“…MAPbI 3 Direct bandgap = 1.5-1.57 eV [16][17][18][19] Diffusion length = 175 μm 20 A high-quality film with low trap density (≈10 10 -10 11 cm À3 ) 21 MAPbI 3Àx Cl x Direct bandgap = 1.5-1.6 eV 22 Diffusion length more than 1 μm 10 Better surface coverage and high-quality film with negligible photocurrent hysteresis 10 Charge carrier mobility is 10-33 cm 2 V À1 s À1 . 9,23 MASnI 3 Direct bandgap = 1.23-1.3 eV [24][25][26] Diffusion length = 500 nm 27 Controllable and pinhole-free uniform film 28 FASnI 3 Direct bandgap = 1.41 eV.…”

Monocrystalline Methylammonium Lead Halide Perovskite Materials for Photovoltaics

“…[28] AVC: MAPI thin films synthesized by combining the AVC and space confined methods were recently obtained for the first time by using trichloroethane (TCE) as antisolvent. [84] The film thickness could be controlled down to 300 nm by adjusting the loading weight of the one of the substrate (Figure 5d) which allowed the thin film to be integrated in a solar cell. However the synthesis was carried out at a temperature of 70 °C, arguably exposing the crystal structure to defects, while attempts to grow crystal at RT has remained so far unsuccessful.…”