Present Status and Future Perspective of Antimony Chalcogenide (Sb2X3) Photovoltaics

Their unique quasi one-dimensional (Q1D) crystal structure and rapid power conversion efficiency (PCE) evolution evoke tremendous scientific and technological interest in antimony chalcogenide (Sb2X3, X = S, Se, or SxSe1–x) photovoltaics (PVs). Solution processability, strong photon harvesting, readily tunable optoelectronic properties, exceptional physicochemical stability, nontoxicity, and earth-abundance are their key features, endorsing Sb2X3 as next-generation PVs. Benign, self-healing grain boundaries and defect-tolerance add to their merits, empowering Sb2X3 films to act like pseudo-single crystals. These semiconductors are born for flexible PVs, as their Q1D crystal structures aid ultrahigh flexibility and bending tolerance. Sb2X3 solar cells are efficient in recycling indoor and ambient light; thus, they are promising as indoor PVs (IPVs). Sb2X3 PVs exhibit potential to simultaneously solve the stability and toxicity issues faced by lead halide perovskite PVs and the cost issues faced by mainstream silicon PVs. Presently, a record certified PCE of 10.7% has been demonstrated by Sb2X3 solar cells; thus, they are emerging as a promising low-cost alternative to the commercially available PV technologies. This review presents a unique perspective of the fundamentals, recent breakthroughs, challenges, and futuristic developments in this field, offering a fundamental guideline for the rational engineering, design, and fabrication of high-PCE Sb2X3 solar cells. This review highlights Sb2X3 based, large area, tandem, and flexible solar cells and explores the commercial viability of this technology from generic power production to niche markets.