Perovskite solar cells (PSCs) are one of the promising photovoltaic technologies for solar electricity generation. NiOx is an inorganic p‐type semiconductor widely used to address the stability issue of PSCs. Although high efficiency is obtained for the devices employing NiOx as the hole transport layer, the fabrication methods have yet to be demonstrated for industrially relevant manufacturing of large‐area and high‐performance devices. Here, it is shown that these requirements can be satisfied by using the magnetron sputtering, which is well established in the industry. The limitations of low fill factor and short‐circuit current commonly observed in sputtered NiOx‐derived PSCs can be overcome through magnesium doping and low oxygen partial pressure deposition. The fabricated PSCs show a high power conversion efficiency of up to 18.5%, along with negligible hysteresis, improved ambient stability, and high reproducibility. In addition, good uniformity is also demonstrated over an area of 100 cm2. The simple and well‐established approach constitutes a reliable and scale method paving the way for the commercialization of PSCs.

A single device with a variety of capabilities is highly attractive for the increasing demands of complex and multifunctional optoelectronics. A hybrid heterojunction formed between CsPbBr 3 halide perovskite and chalcogenide quantum dots is demonstrated. The heterojunction served as an asymmetric active layer allows not only charge separation/exciton dissociation in a benign process, but also carrier injection/recombination with the suppression of bulk and interfacial nonradiative recombination. An individual device incorporating such a heterojunction is therefore implemented with an integration of proof-of-concept functions, including a voltage controllable multicolor light-emitting diode, an exceptionally high photovoltage energy-harvesting device, and an ultrafast photosensitive detector. The figures of merit of the light-emitting diode remarkably surpass those of the corresponding singleactive-layer device, particularly in terms of its bright electroluminescence and superior long-term stability. The asymmetric active layer concept provides a feasible route to design efficient multifunctional and monofunctional devices in the future.

Electroluminescent devices based on metal halide perovskites have attracted extensive attention owing to their high external quantum efficiency, excellent color purity, and inexpensive solution process. So far, extensive efforts have been made to improve the efficiency of the monochromatic perovskite light‐emitting diodes (LEDs). However, multicolor perovskite‐based LEDs are seldom studied. Here, an individual device capable of multicolor emission in response to the passage of external electric bias is demonstrated. With the rational design of the energy band alignment and control of the carrier transport property, color‐tunable electroluminescent devices based on inorganic halide perovskite and chalcogenide quantum‐dots are fabricated with a wide color tuning range, high color reversibility, and ultrafast color switching. The mechanism of chromaticity tuning is investigated and is explained by the shift of the exciton recombination zone with the driving voltage. The presented work will impact scientific communities by encouraging the manufacture of cost‐effective, high‐resolution, and full‐color displays and human‐centric lighting.