Toward Clean and Economic Production of Highly Efficient Perovskite Solar Module Using a Cost-Effective and Low Toxic Aqueous Lead-Nitrate Precursor

Toxic substance usage remains one of the major concerns that must be addressed toward the commercialization of perovskite photovoltaics. Herein, we report a highly efficient perovskite solar module (>13%) fabricated via a wet process that uses a unique aqueous Pb(NO3)2 precursor, eliminating the use of toxic organic solvents during perovskite film preparation. In addition, we demonstrate a unique pattern in a monolithically interconnected module structure to check the uniformity of perovskite film and the quality of laser scribing. Finally, we highlight that this aqueous Pb(NO3)2 precursor protocol could achieve an enormous cost reduction over conventional PbI2 organic solutions whether in the laboratory research stage or at mass production scale, strengthening the core competitiveness of perovskite solar cells in the Darwinian ocean of photovoltaic technologies

One-Pot Electrodeposition of Compact Layer and Mesoporous Scaffold for Perovskite Solar Cells

In this study, we report a facile method to sequentially electrodeposit a TiO₂ compact layer and a mesoporous scaffold from a single solution. This bilayer TiO₂ structure offers good controllability on the thickness and morphology by simply adjusting the depositing parameters. Currently, perovskite solar cell containing an electrodeposited TiO₂ bilayer exhibits similar power conversion efficiency when compared with the one using double spin-coating techniques, showing great potential to replace conventional tedious TiO₂ film fabrication

Crystal Growth and Dissolution of Methylammonium Lead Iodide Perovskite in Sequential Deposition: Correlation between Morphology Evolution and Photovoltaic Performance

Crystal morphology and structure are important for improving the organic–inorganic lead halide perovskite semiconductor property in optoelectronic, electronic, and photovoltaic devices. In particular, crystal growth and dissolution are two major phenomena in determining the morphology of methylammonium lead iodide perovskite in the sequential deposition method for fabricating a perovskite solar cell. In this report, the effect of immersion time in the second step, i.e., methlyammonium iodide immersion in the morphological, structural, optical, and photovoltaic evolution, is extensively investigated. Supported by experimental evidence, a five-staged, time-dependent evolution of the morphology of methylammonium lead iodide perovskite crystals is established and is well connected to the photovoltaic performance. This result is beneficial for engineering optimal time for methylammonium iodide immersion and converging the solar cell performance in the sequential deposition route. Meanwhile, our result suggests that large, well-faceted methylammonium lead iodide perovskite single crystal may be incubated by solution process. This offers a low cost route for synthesizing perovskite single crystal

Nucleus Near-Infrared (nNIR) Irradiation of Single A549 Cells Induces DNA Damage and Activates EGFR Leading to Mitochondrial Fission

There has been great interest in identifying the biological substrate for light-cell interaction and their relations to cancer treatment. In this study, a near-infrared (NIR) laser is focused into the nucleus (nNIR) or cytoplasm (cNIR) of a single living cell by a high numerical aperture condenser to dissect the novel role of cell nucleus in mediating NIR effects on mitochondrial dynamics of A549 non-small cell lung cancer cells. Our analysis showed that nNIR, but not cNIR, triggered mitochondrial fission in 10 min. In contrast, the fission/fusion balance of mitochondria directly exposed to cNIR does not change. While the same phenomenon is also triggered by single molecular interactions between epidermal growth factor (EGF) and its receptor EGFR, pharmacological studies with cetuximab, PD153035, and caffeine suggest EGF signaling crosstalk to DNA damaging response to mediate rapid mitochondrial fission as a result of nNIR irradiation. These results suggest that nuclear DNA integrity is a novel biological target for cellular response to NIR

Crown Ether Modulation Enables over 23% Efficient Formamidinium-Based Perovskite Solar Cells

The use of molecular modulators to reduce the defect density at the surface and grain boundaries of perovskite materials has been demonstrated to be an effective approach to enhance the photovoltaic performance and device stability of perovskite solar cells. Herein, we employ crown ethers to modulate perovskite films, affording passivation of undercoordinated surface defects. This interaction has been elucidated by solid-state nuclear magnetic resonance and density functional theory calculations. The crown ether hosts induce the formation of host-guest complexes on the surface of the perovskite films, which reduces the concentration of surface electronic defects and suppresses nonradiative recombination by 40%, while minimizing moisture permeation. As a result, we achieved substantially improved photovoltaic performance with power conversion efficiencies exceeding 23%, accompanied by enhanced stability under ambient and operational conditions. This work opens a new avenue to improve the performance and stability of perovskite-based optoelectronic devices through supramolecular chemistry

OligonucleotidesAssembled Au Nanorod-Assisted Cancer Photothermal Ablation and Combination Chemotherapy with Targeted Dual-Drug Delivery of Doxorubicin and Cisplatin Prodrug

External stimuli responsive dual drugs carrier was synthesized with Au nanorods (NRs) as the platform. On Au NRs, single stranded DNAs were assembled using 5′ thiol end. Following this, complementary DNA (cDNA) strands were hybridized. This hybridized double stranded DNA facilitated doxorubicin (Dox) intercalation into the duplexes. The cDNA designed with the 5′ amine functional group assisted to tether platinum [Pt­(IV)] prodrugs by establishing amide bond with the acid group at the axial ligand. The other axial acid group in Pt­(IV) prodrugs was conjugated with the folic acid (FA) to target folate receptors overexpressed in the cancer cells. This targeting vehicle provided remote-controlled delivery of this high toxic cargo cocktail at the tumor site, ensuring extra specificity that can avoid acute toxicity, where release of Dox and Pt­(IV) was achieved upon NIR 808 nm diode laser irradiation. The dehybridization set the Dox free to bind the cell nucleus and cellular reductants reduced Pt­(IV) to yield toxic Pt­(II), becoming an active drug. The in vitro and in vivo studies revealed that this external stimulus responsive combination drug delivery was significantly effective

A universal co-solvent dilution strategy enables facile and cost-effective fabrication of perovskite photovoltaics

Cost management and toxic waste generation are two key issues that must be addressed before the commercialization of perovskite optoelectronic devices. We report a groundbreaking strategy for eco-friendly and cost-effective fabrication of highly efficient perovskite solar cells. This strategy involves the usage of a high volatility co-solvent, which dilutes perovskite precursors to a lower concentration (<0.5 M) while retaining similar film quality and device performance as a high concentration (>1.4 M) solution. More than 70% of toxic waste and material cost can be reduced. Mechanistic insights reveal ultra-rapid evaporation of the co-solvent together with beneficial alteration of the precursor colloidal chemistry upon dilution with co-solvent, which in-situ studies and theoretical simulations confirm. The co-solvent tuned precursor colloidal properties also contribute to the enhancement of the stability of precursor solution, which extends its processing window thus minimizing the waste. This strategy is universally successful across different perovskite compositions, and scales from small devices to large-scale modules using industrial spin-coating, potentially easing the lab-to-fab translation of perovskite technologies

Self‐Aligned Contact Doping for Performance Enhancement of Low‐Leakage Carbon Nanotube Field Effect Transistors

Abstract Carbon nanotube (CNT) field effect transistors (CNFETs) show promise for the next generation VLSI systems due to their excellent scalability, energy efficiency, and speed. However, high leakage current is a drawback of large diameter CNTs (diameter (DCNT) ≥ 1.4 nm) due to the small electronic band gap (EG) ≤ 0.6 eV and effective mass. This work investigates the on‐current and off‐current tradeoff for two populations of semiconducting‐enriched CNT with DCNT ≈ 1.0 nm displaying a simultaneous 50x improvement in minimun current (IMIN) with 2.5x degradation in contact resistance compared to DCNT ≈ 1.4 nm using a Pd side‐bonded contact. A method to enhance the performance of low‐leakage CNFETs is demonstrated using sub‐monolayer self‐aligned contact doping with 0.8 nm of MoOX, which delivers a 57% reduction in contact resistance to DCNT ≈ 1.0 nm. Robustness is verified after annealing at 200 °C for 30 min and monitoring stability across 6 months post‐fabrication with no change in electrical behaviors

Multimodal host-guest complexation for efficient and stable perovskite photovoltaics

Formamidinium lead iodide perovskites are promising light-harvesting materials, yet stabilizing them under operating conditions without compromising optimal optoelectronic properties remains challenging. We report a multimodal host-guest complexation strategy to overcome this challenge using a crown ether, dibenzo-21-crown-7, which acts as a vehicle that assembles at the interface and delivers Cs+ ions into the interior while modulating the material. This provides a local gradient of doping at the nanoscale that assists in photoinduced charge separation while passivating surface and bulk defects, stabilizing the perovskite phase through a synergistic effect of the host, guest, and host-guest complex. The resulting solar cells show power conversion efficiencies exceeding 24% and enhanced operational stability, maintaining over 95% of their performance without encapsulation for 500h under continuous operation. Moreover, the host contributes to binding lead ions, reducing their environmental impact. This supramolecular strategy illustrates the broad implications of host-guest chemistry in photovoltaics. It remains a challenge to achieve a balance between performance and stability, as well as addressing the environmental impact of perovskite solar cells. Here, the authors propose a multimodal host-guest complexation strategy enabling these shortcomings to be addressed simultaneously