“…[5][6][7] As a result, the power-conversion efficiency (PCE) of the perovskite solar cells (PSC) has reached 25.2 %. [9,10] However, owing to a lack of deep-understanding of fabrication methods and the underlying mechanisms, a majority of perovskite thin films being reported are [001]-or randomly oriented ones, [11,12,22] leaving the perovskites oriented in [100] direction relatively less understood. [9,10] However, owing to a lack of deep-understanding of fabrication methods and the underlying mechanisms, a majority of perovskite thin films being reported are [001]-or randomly oriented ones, [11,12,22] leaving the perovskites oriented in [100] direction relatively less understood.…”