The simple-structural and volatile solid additive 1,4-dibromobenzene (DBrB) can outperform organic solar cells (OSCs) fabricated with 1,4-diiodobenzene and 1,4-dichlorobenzene in terms of power conversion efficiency (PCE). A remarkable PCE of 17.0% has been achieved in a binary OSC based on DBrB-optimized photoactive materials processed from non-halogenated solvents, which is mainly attributed to the formation of a three-dimensional interpenetrating network and the orderly arrangement of the photoactive materials by improving the intermolecular interaction. This optimized morphology enables efficient charge transfer/transport as well as suppressed charge recombination, resulting in the simultaneous increase in all photovoltaic parameters. More importantly, we demonstrate that non-halogenated solvent-processed DBrB enabled PM6:Y6-HU OSCs with an impressive PCE of 18.6%, which is the highest efficiency yet reported for binary OSCs. This study suggests that the novel DBrB volatile solid additive is an effective approach to optimizing the morphology and thereby improves the photovoltaic performance of OSCs.
Herein, we synthesized Cr3+/Ln3+ (Er3+, Tm3+)-codoped rare earth-based Cs2NaScCl6 double perovskite, and the near-infrared emission of Ln3+ can be excited by visible light through the energy transfer (ET) from Cr3+ to Ln3+. Moreover, there are two independent emission bands, which stems from 4T2 → 4A2 transition of Cr3+ (970 nm) and f-f transition of Ln3+ (1542 nm for Er3+ and 1220 nm for Tm3+), respectively. Particularly, both compounds have ultra-high photoluminescence quantum yield (PLQY) of 60% for 10%Cr3+/6%Er3+-codoped Cs2NaScCl6 (Er3+ emission: ~26%) and 68% for 10%Cr3+/4.5%Tm3+-codoped Cs2NaScCl6 (Tm3+ emission: ~56%), which can be attributed to the ultra-high ET efficiency from Cr3+ to Ln3+ and the similar ionic activity of Sc3+ and Ln3+ allowing more dopants enter the host lattice. Considering the excellent stability of the samples, we demonstrated Cr3+/Tm3+-codoped Cs2NaScCl6 in the applications of near-infrared imaging and night vision. Finally, we reported 10%Cr3+/4.5%Tm3+/9%Er3+-tridoped Cs2NaScCl6 and further applied it for optical thermometry.
The practical implementation of aqueous Zn-ion batteries (ZIBs) for large-scale energy storage is impeded by the challenges of water-induced parasitic reactions and uncontrolled dendrite growth. Herein, we propose a strategy to regulate both anions and cations of electrolyte solvation structures to address above challenges, by introducing an electrolyte additive of 3-hydroxy-4-(trimethylammonio)butyrate (HTMAB) into ZnSO4 electrolyte. Consequently, the deposition of Zn is significantly improved leading to a highly reversible Zn anode with paralleled texture. The Zn/Zn cells with ZnSO4/HTMAB exhibit outstanding cycling performance, showcasing a lifespan exceeding 7500 h and an exceptionally high accumulative capacity of 16.47 Ah cm−2. Zn/NaV3O8·1.5H2O full cell displays a specific capacity of ~130 mAh g−1 at 5 A g−1 maintaining a capacity retention of 93% after 2000 cycles. This work highlights the regulation on both cations and anions of electrolyte solvation structures in optimizing interfacial stability during Zn plating/stripping for high performance ZIBs.
Anion exchange is an effective strategy to regulate the composition and optoelectronic properties of perovskite quantum dots (PQDs). Though promising, it is more desirable to synthesize PQDs to avoid the decrease of photoluminescence quantum yield (PLQY). Herein, we developed a ligand mediated anion exchange approach, in which the phase transition from CsPbBr3 QDs to CsPbI3 QDs was observed with the introduction of N-Acetyl-L-cysteine (NAC) and 1,3-dimethylimidazolium iodide (DMII) aqueous solution in CsPbBr3 QDs solution. NAC is expected to create more halogen vacancies in CsPbBr3 QDs, which provides sufficient adsorption sites for I− ions, resulting in accelerating the anion exchange rate in the process of DMII incorporation. Benefiting from the synergistic ligand mediated anion exchange, high PLQY of 97% and remarkable stability of CsPbI3 QDs are obtained. Furthermore, a white light-emitting diode (WLED) with a lumen efficiency (LE) of 116.82 lm/W is constructed, showing remarkable stability under continuous operation.
Perovskite solar cells offer a promising future for next-generation photovoltaics owing to numerous advantages such as high efficiency and ease of processing. However, two significant challenges, air stability, and manufacturing costs, hamper their commercialization. This study proposes a solution to these issues by introducing a floating catalyst-based carbon nanotube (CNT) electrode into all-inorganic perovskite solar cells for the first time. The use of CNT eliminates the need for metal electrodes, which are primarily responsible for high fabrication costs and device instability. The nanohybrid film formed by combining hydrophobic CNT with polymeric hole-transporting materials acted as an efficient charge collector and provided moisture protection. Remarkably, the metal-electrode-free CNT-based all-inorganic perovskite solar cells demonstrated outstanding stability, maintaining their efficiency for over 4000 h without encapsulation in air. These cells achieved a retention efficiency of 13.8%, which is notable for all-inorganic perovskites, and they also exhibit high transparency in both the visible and infrared regions. The obtained efficiency was the highest for semi-transparent all-inorganic perovskite solar cells. Building on this, a four-terminal tandem device using a low-band perovskite solar cell achieved a power conversion efficiency of 21.1%. These CNT electrodes set new benchmarks for the potential of perovskite solar cells with groundbreaking device stability and tandem applicability, demonstrating a step toward industrial applications.