Due to the higher photon energy under indoor photovoltaic conditions, using perovskite materials with wider bandgaps has become a consensus. However, updating perovskite absorbers requires additional adaptations involving at least two layers of transport materials and two interfaces, increasing the development complexity. This study acknowledges that the buried interface is the primary location for the generation of photoinduced carriers, and achieving efficient carrier separation and transport at this interface will solve most of the open circuit voltage (V-OC) loss issues encountered in transitioning from solar photovoltaics to indoor photovoltaics. Therefore, a class of bipolar pseudohalide ammonium salts is proposed for use as bridging agents for the buried interface to effectively resolve the issues of lattice misalignment and insufficient carrier driving force at the buried interface when broadening the perovskite bandgap, thereby reducing V-OC loss in indoor photovoltaics. The optimized device exhibits an excellent photoelectric conversion efficiency (PCE) of 41.04%, with a record-high V-OC of 1.08 V. It also demonstrates impressive long-term operational stability with a T-80 lifetime of 1000 h. Substituting various non-buried interface transport materials and different categories of wide-bandgap perovskite absorbers does not alter the effectiveness, proving its universality.

Modern electronics face formidable challenges in energy efficiency and durability. Owing to their safety, lightweight design, and simplicity, indoor photovoltaics (IPVs) have garnered substantial attention among various sustainable power sources. Remarkable progress is made in IPVs, achieving power conversion efficiencies (PCEs) ranging from 3.6% using silicon materials in 2011 to an impressive 42.43% using current perovskite materials. Although numerous summaries exist, most reviews of IPVs have narrowly focused on single active materials and lack a systematic overview across different material categories starting from fundamental design principles. This comprehensive review addresses this knowledge gap by introducing IPVs fabricated based on silicon, dye, III-V, organic, and perovskite materials, compares the PCEs of these devices for indoor applications, and provides an overview of the advantages and disadvantages associated with the different materials. For the most promising materials, optimization and modification schemes are presented for perovskite-based IPVs. The standardized testing of IPVs and urgent challenges encountered in their development are emphasized. This review offers valuable guidance for material selection and device design for future IPVs to facilitate PCE improvement and challenge resolution in the field of IPVs. Modern electronics encounter challenges in energy efficiency and durability. Indoor photovoltaics (IPVs) have emerged as a sustainable power source. This review provides the advantages and disadvantages of IPVs based on silicon, dye, III-V, organic, and perovskite materials. Furthermore, the optimization schemes for perovskite-based IPVs and standardized testing of IPVs are also discussed.image

Perovskite solar cells (PSCs) have achieved remarkable progress in the past decade and become the most powerful challenger of traditional silicon photovoltaics. Among the many designs, bifacial PSCs have received widespread attention these days due to their ability to fully utilize environmental reflection and scattering light to enhance energy yield. They also can provide better aesthetic design for building-integrated photovoltaics (BIPVs). However, the potential of bifacial PSCs is not limited to these traditional applications. Importantly, such architecture also serves as a universal component for multi-junction cells and photon engineering, which are both critical for further efficiency improvement. In this review, the requirements of different functional layers under various applications are described in detail, starting from the structure of bifacial PSCs. The application developments are introduced, including albedo utilization, semitransparent PSCs (ST-PSCs), TSCs. The present issues (such as stability, large area, recombination of carriers at the back electrode and toxicity etc.) and the extra challenges of bifacial PSCs are highlighted. It is hoped that this review can provide new ideas for the future development and further improve the competitiveness of PSCs.

Single crystal is the most advantageous of the crystalline states of halide perovskites. It displays better optical and electrical capabilities than polycrystalline films and microcrystals due to their inherent structural advantages, such as free grain boundaries, long-range ordered structure, and high orientation. Single-crystal perovskite materials can theoretically enable optoelectronic devices with higher performance and stronger stability. In this review, the intrinsic physical properties of perovskite single crystals are analyzed. The most recent advances in single-crystal optoelectronic devices are reviewed, and the design principles of the devices under different application conditions are revealed. It provides potential solutions for remaining challenges, and it is expected to accelerate the development of perovskite based optoelectronic devices.

Perovskite solar cells offer great potential as a sustainable power source for distributed electronic devices that operate indoors. However, the impact of advanced lighting technology, especially the widely used pulse width modulation (PWM) technology, on perovskite photovoltaics has been ignored. Herein, for the first time in photovoltaics, we find that the light impact emitted by the PWM lighting system caused dynamic strain in perovskite thin films, induced phase separation, and accelerated the generation of metallic lead (Pb0) defects, leading to irreversible degradation of the cell performance after 27 h (T80). To address this issue, formamidinium triiodide (FAI3) is chosen to treat the surface of the perovskite and release residual stress, resulting in reduced lattice deformation during dynamic strain processes. Meanwhile, it suppresses harmful Pb0 defects and reduces Voc loss at low light intensity. The champion device achieves impressive power conversion efficiency (PCE) of 35.14% and retains 99.5% of the initial PCE after continuous strobe light soaking for 2160 h.