  The alloy strategy through A- or X-site is a common method for experimental
preparation of high-performance and stable lead-based perovskite solar cells.
As one of the important candidates for lead-free and stable photovoltaic
absorber, the inorganic antiperovskite family has recently been reported to
exhibit excellent optoelectronic properties. However, the current reports on
the design of antiperovskite alloys are rare. In this work, we investigated the
previously overlooked electronic property (e.g., conduction band convergence),
static dielectric constant, and exciton binding energy in inorganic
antiperovskite nitrides by first-principles calculations. Then, we reveal a
linear relationship between tolerance factor and various physical quantities.
Guided by the established structure-composition-property relationship in six
antiperovskite nitrides X3NA (X2+ = Mg2+, Ca2+, Sr2+; A3- = P3-, As3-, Sb3-,
Bi3-), for the first time, we design a promising antiperovskite alloy
Mg3NAs0.5Bi0.5 with the quasi-direct band gap of 1.402 eV. Finally, we make a
comprehensive comparison between antiperovskite nitrides and conventional
halide perovskites for pointing out the future direction for device
applications.
