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Developing hole-transport materials (HTMs) with high hole mobility is critical for constructing efficient perovskite solar cells (PSCs). We present a design strategy for improving hole mobility and PSC performance using a stable zinc complex-based HTM BPZ23. Compared to its non-metal counterpart (BP21), the BPZ23 demonstrated a 59.42% increase in hole mobility, resulting in a good perovskite layer with reduced trap-assisted recombination. As a result, the power conversion efficiency of the fabricated inverted PSC using BPZ23 is up to 19.75%, which is one of the highest reported for any transition metal complex-based HTM employed in inverted PSC. This research demonstrates a simple and efficient method for increasing hole mobility in HTMs and improving the photovoltaic performance of PSCs. [ABSTRACT FROM AUTHOR]

The present study describes the design of a simple teaching module for each student to fabricate a dye-sensitized solar cell (DSSC) that could power a small fan motor. The significance of this laboratory exercise is to stimulate students' motivation by visualizing the light being converted into electricity, which is then switched over to kinetic energy, and to inspire them to understand the mechanistic working principles of solar cells and gain the concepts of sustainable green energy. The developed DSSC teaching module could easily power a small fan motor under the light of a halogen lamp, a conventional light bulb, or a compact fluorescent lamp. In addition, the fabrication process allowed replacing the expensive massive pressing machine by using electric irons that are readily available in daily life and made this module cost-effective and easy to assemble by school students. The field studies reveal that both junior and senior high school students were able to complete the module in 2.5 h class session and more than 80% of students successfully constructed the DSSCs to harvest the light to propel their fan motors.

Hole mobility is critical to the power conversion efficiencies of perovskite solar cells (PSCs). Organic small‐molecule hole‐transporting materials (HTMs) have attracted considerable interest in PSCs due to their structural flexibility and operational durability, but they suffer from modest hole mobility. On the other hand, inorganic HTMs with good hole mobility are inflexible in structural variation and exhibit unsatisfactory cell efficiency. In this study, a ligand BT28 and its zinc‐based coordination complex BTZ30 were synthesized, characterized, and investigated as HTMs for PSC applications. The mixed‐halide perovskites can be grown uniformly with large crystalline grains on both HTMs, which exhibit similar optical and electrochemical properties. However, it was discovered that the BTZ30‐based solar cell exhibited an open‐circuit voltage of 1.0817 V and a high short‐circuit current density of 23.1392 mA cm−2 with a champion power conversion efficiency of close to 20 %. The performance difference between the two HTMs can be attributed to the difference in their hole mobilities, which is 63.31 % higher for BTZ30 than BT28. The comparison of non‐metal and metal HTMs revealed the importance of considering hybrid structures to overcome some shortcomings associated with organic and inorganic HTMs and achieve high‐performance PSCs. [ABSTRACT FROM AUTHOR]

The hole‐transporting material (HTM) in perovskite solar cells (PSCs) provides an ideal interface with the perovskite layer for hole collection while influencing the perovskite crystalline structure and morphology. This article presents SIM and DIM, two new dopant‐free imidazolium‐based HTMs with charged units accompanied by counter ions that show the potential to function as ionic HTMs and ionic liquid additives and help improve the efficiency and stability of inverted PSCs. DIM‐based PSCs demonstrates exceptional performance with a high‐power conversion efficiency of 19.15%, attributed to improved passivation of perovskite interface defects. Furthermore, these new imidazolium salt‐based HTMs can be manufactured economically, making them a viable option for mass production and PSC commercialization. [ABSTRACT FROM AUTHOR]

Due to the excellent thermal property of Na superionic conductors (NASICON), research has focused on studying crystal structure parameters under high temperature conditions. In this study, different ratios of anion groups were regulated to induce vacancy defects on the Eu-doped phosphate phosphor Na2.87Sc2(PO4)y:0.13Eu2+, y = 2.6–3.0. When the amount of the anion group increased, a structural transformation was induced from γ to β-phase. Using the X-ray absorption near edge structure (XANES) technique, this phenomenon was found to be caused by Eu3+ and Eu2+ coexisting due to the amount of anion group. It is rare to observe this situation with 2D X-ray fluorescence (XRF) technology, with direct evidence of the shielding effect provided by XRF mapping. We speculate that the oxidation reaction creates trivalent europium due to the lack of the –PO4 anion group to protect the divalent europium (Eu2+) and we explain the luminescence mechanism by a charge compensation model. Thermal stability was maintained at 90% from room temperature to 150 °C. The pathway of the reduction mechanism and the location of the ground level from Eu2+ (β-phase) to Eu3+ (γ-phase) are evidenced by high-pressure spectroscopy. Finally, this study proposes a generic path for the anion group phosphor research. [ABSTRACT FROM AUTHOR]