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[Display omitted] • Bilateral passivation strategy by PEACl doping and NPB post-treatment is proposed. • Construction of GHJ provides a favorable transport pathway for hole migration. • Achieving a PCE of 21.88% for PEACl-SnO 2 -NPB based PSCs with negligible hysteresis. • Improved moisture and thermal stability of PSCs by using synchronous regulation. Defects and inferior charge transport dynamics within devices are key issues that inhibit the improvements of photovoltaic performance and stability. Developing facile and feasible strategies for synchronous passivation of defects regarding charge transport layers (CTLs), perovskite films and their interfaces, and precise tuning of energy level structure, is a definite way to solve above problems. Herein, we develop a synergistic passivation strategy for perovskite films and bilateral interfaces to improve device performance. Firstly, an appropriate amount of phenylethylammonium chloride is adopted to modify SnO 2 electron transport layer (ETL). The complexation reaction between N atoms in –NH 2 and Sn4+ improve the agglomeration of SnO 2 nanoparticles and film quality of SnO 2 ETL. The presence of Cl− ions not only effectively fill oxygen vacancies within SnO 2 ETL, but also participate in regulating crystal growth dynamics of perovskite films, thus improving electron transport properties at interface. Subsequently, p-type conducting material N,N'-Bis-(1-naphthalenyl)-N,N'-bis-phenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) is introduced into anti-solvent chlorobenzene during the preparation of perovskite films to further regulate the crystal quality and achieve full-range defect passivation. Particularly, the introduction of NPB helps to construct a gradient heterojunction between upper perovskite film and SpiroOMeTAD hole transport layer, thus reducing the accumulation of hole carriers near interface and further suppressing current–voltage hysteresis behavior of devices. Additionally, the hydrophobicity of NPB and full range of defect passivation greatly enhance the humidity and thermal stability of devices. Finally, a high power conversion efficiency of 21.88% is obtained with suppressed hysteresis and enhanced long-term stability. This work highlights the role of full-range defect passivation on CTLs, perovskite absorption layers and interfacial charge transport properties, which provide a novel concept for constructing high-performance and stable perovskite devices. [ABSTRACT FROM AUTHOR]

• We developed a "hillocks"-like random-textured perovskite (HRT-perovskite) absorber. • Crystallization kinetics and formation mechanisms of CB-induced HRT-perovskite absorbers have been proposed. • Proper volume CB promoted the construction of porous MAI-PbI 2 -DMSO intermediate structure. • Efficient light trapping was achieved by employing CB-induced HRT-perovskite absorbers. Efficient planar heterojunction perovskite solar cells (PSCs) with high-quality absorbers are promising for flexible-, semitransparent-, and tandem- photovoltaic applications. However, compared to mesoporous PSCs, planar perovskite absorbers tend to suffer from additional optical losses due to insufficient light harvesting. Accordingly, the design and fabrication of high-quality textured perovskite absorbers are promising to improve device performance. We developed a "hillocks"-like random-textured perovskite (HRT-perovskite) absorber using a facile chlorobenzene (CB) anti-solvent assisted spin-coating approach. The crystallization kinetics and formation mechanisms of CB-induced HRT-perovskite absorbers have been systematically explored, allowing us to gain insights into the role of CB, i.e. an appropriate volume of CB promotes the formation of a porous MAI-PbI 2 -DMSO intermediate structure. We show that the porous nature of the intermediate film provides sufficient space for lattice reconstruction and structure expansion during crystal growth, thus effectively improving the film and surface/interface quality, and, ultimately, the optoelectronic properties of the perovskite absorber. Moreover, the HRT-perovskite absorber exhibits excellent light-trapping capability and carrier mobility, due to its optimized surface roughness and longitudinally ordered grain boundary distribution. As a result, we obtained efficiencies of up to 20.03% from planar heterojunction PSCs fabricated using ~400 nm thick HRT-perovskite absorbers. The process exhibits very high reproducibility with 20 individual devices fabricated in one batch, achieving an average power conversion efficiency (PCE) of 19.00%. Finally, the whole fabrication process was conducted below 150 ℃, which is appropriate for a wide range of applications, such as flexible- and tandem- photovoltaic devices. [ABSTRACT FROM AUTHOR]