Electrosprayed Polymer-Hybridized Multidoped ZnO Mesoscopic Nanocrystals Yield Highly Efficient and Stable Perovskite Solar Cells

Abstract

Solid-state perovskite solar cells have been expeditiously developed since the past few years. However, there are a number of open questions and issues related to the perovskite devices, such as their long-term ambient stability and hysteresis in current density–voltage curves. We developed highly efficient and hysteresis-less perovskite devices by changing the frequently used TiO 2 mesoscopic layer with polymer-hybridized multidoped ZnO nanocrystals in a common n–i–p structure for the first time. The gradual adjustment of ZnO conduction band position using single- and multidopant atoms will likely enhance the power conversion efficiency (PCE) from 8.26 to 13.54%, with PCE max = 15.09%. The highest PCE avg of 13.54% was demonstrated by 2 atom % boron and 6 atom % fluorine co-doped (B, F:ZnO) nanolayers (using optimized film thickness of 160 nm) owing to their highest conductivity, carrier concentration, optical transmittance, and band-gap energy compared to other doped films. We also successfully apply a fine polyethylenimine thin layer on the doped ZnO nanolayers, causing the reduction in work function and overall demonstrating the enhancement in PCE from ∼10.86% up to 16.20%. A polymer-mixed electron-transporting layer demonstrates the remarkable PCE max of 20.74% by decreasing the trap sites in the oxide layer that probably reduces the chances of carrier interfacial recombination originated from traps and thus improves the device performance. Particularly, we produce these electron-rich multidoped ZnO nanolayers via electrospray technique, which is highly suitable for the future development of perovskite solar cells.

Overcoming Zinc Oxide Interface Instability with a Methylammonium‐Free Perovskite for High‐Performance Solar Cells

“…Recent efforts have increased PCE for ZnO‐based PSC to over 20% by addressing these stability concerns by “passivating” the surface with magnesium oxide, ethanolamine, polyethylenimine, and ZnS . Despite these improvements however, the reactions of methylammonium cations at ZnO interfaces have remained unresolved, limiting the long‐term stability of ZnO–perovskite solar cells.…”

Reutilizing Methane Reforming Spent Catalysts as Efficient Overall Water-Splitting Electrocatalysts

“… 2 , 3 Hydrogen is pacing up to lead the global race of energy requirement, with an increasing current demand of 70 Mt of H 2 /year. 4 − 6 Currently, emission-intensive processes predominantly used for hydrogen production are methane reforming (i.e., produces 7 kg CO 2 /kg H 2 ) and coal gasification (i.e., produces 18–20 kg CO 2 /kg H 2 ), which results in wasting a large amount of catalyst due to the growth of carbon over the catalyst surface. 7 − 11 In 2009, it was reported that about 150 000–170 000 tons of catalyst from hydroprocessing was deactivated or spent annually, with about an annual increase of 5%, which is predicted to be now in the range of 232 500–263 500 t/year.…”

Recent advances in fiber-shaped and planar-shaped textile solar cells

“…Hence, many research efforts have been invested on improving the performance, efficiency and stability of different types of emerging photovoltaics (PVs) such as dye sensitized, [1][2][3][4][5][6][7][8][9][10] organic, [11][12][13][14][15][16][17][18][19][20][21][22] and perovskite PVs. [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42] While conventional silicon solar cells are heavy, fragile, and rigid, flexible solar cells represent a good alternative to the silicon counterparts, because of not only their flexibility, but also their lightweight, which enable their integration in portable electronic applications. Recently, scientists have carried out significant research and development efforts in order to improve the performance and the stability of flexible solar cells.…”