Manipulating the adhesion of electroless plated Cu film on liquid polymer crystal substrate for advanced microelectronic manufacturing.

The evolution from subtractive to modified semi-additive (mSAP) and semi-additive (SAP) processes has heightened the importance of electroless plated (ELP) copper (Cu) peel strength in the printed circuit board industry. This study introduces a wet process for depositing Cu on liquid crystal polymer (LCP) using advanced electroless plating, incorporating a polyethylenimine (PEI) surfactant, a homemade nano-sized palladium (Pd) activator, and a micro-sculpturing treatment. By adjusting PEI immersion time and substrate roughness in the sub-micrometer domain, the peel strength of the ELP Cu film ranges from under 10 gf/cm to over 600 gf/cm.

Complementary Operando Electrochemical Quartz Crystal Microbalance and UV/Vis Spectroscopic Studies: Acetate Effects on Zinc-Manganese Batteries.

Zinc-ion batteries, in which zinc ions and protons do intercalation and de-intercalation during battery cycling with various proposed mechanisms under debate, have been studied. Recently, electrolytic zinc-manganese batteries, exhibiting the pure dissolution-deposition behavior with a large charge capacity, have been accomplished through using electrolytes with Lewis acid. However, the complicated chemical environment and mixed products hinder the investigation though it is crucial to understand the detailed mechanism.

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.

Choline chloride-based deep eutectic solvents as effective electrolytes for dye-sensitized solar cells.

Electrolytes for dye-sensitized solar cells remain a challenge for large-scale production and commercialization, hindering the wide application of solar cells. We have developed two new electrolyte-based deep eutectic solvents using a mixture of choline chloride with urea and with ethylene glycol for dye-sensitized solar cells. The prominent features of the two deep eutectic solvent electrolytes are simple preparation for large-scale production with inexpensive, available, and nontoxic starting materials and biodegradability.

Structural Engineering of Organic D-A-π-A Dyes Incorporated with a Dibutyl-Fluorene Moiety for High-Performance Dye-Sensitized Solar Cells.

Structural engineering of the light-harvesting dyes employed in DSSCs (dye-sensitized solar cells) with a systematic choice of the electron-donating and -accepting groups as well as the π-bridge allows the (photo)physical properties of dyes to match the criteria needed for improving the DSSC efficiency. Herein, we report an effective approach of molecular engineering of DSSC sensitizers, aiming to gain insights on the configurational impact of the fluorenyl unit on the optoelectronic properties and photovoltaic performance of DSSCs. Five new organic dyes (, , , , and ) with a D-A-π-A framework integrated with a fluorenyl moiety were designed and synthesized for DSSCs.

Double Fence Porphyrins that are Compatible with Cobalt(II/III) Electrolyte for High-Efficiency Dye-Sensitized Solar Cells.

A series of new double fence porphyrin dyes bJS1-bJS3, with eight long alkoxyl chains attached to four β-phenyl groups, have been designed and synthesized. The single fence meso-substituted counterparts mJS1-mJS3 were also prepared as reference dyes. Dyes bJS1-bJS3 and mJS1-mJS3 exhibit power conversion efficiencies of 8.

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.

Electrochemical activation of polymer chains mediated with radical transfer reactions.

This work demonstrates a general and effective approach to activate inert polymer chains for further reactions through electrochemically driven radical generation and radical transfer reactions. The generated radical-containing polymer chains show capacity for further polymer reactions and preparation of polymer hybrids.

-Butylpyridine Coordination with [Cu(dmp)] Redox Couple and Its Connection to the Stability of the Dye-Sensitized Solar Cell.

Cu(I)/(II) complex redox couples in dye-sensitized solar cell (DSSC) are of particular interest because of their low reorganization energy between Cu(I) and Cu(II), which minimizes the potential loss during sensitizer regeneration, thus allowing the open-circuit voltage of the device to go over 1.0 V. However, Cu(I)/(II)-based redox couples are reported to coordinate with 4--butylpyridine (TBP), which is a standard additive in the electrolyte, and this is believed to account for the poor durability of a Cu(I)/(II)-based DSSCs.

Photomask-Free, Direct Selective Electroless Deposition on Glass by Controlling Surface Hydrophilicity.

This paper reports a new approach to realize direct selective electroless deposition (ELD) without the requirement of photolithography. This method involves sequential silane-compound modifications in which the first modification creates a hydrophobic surface on the TiO-coated glass using a fluorine-rich alkoxysilane compound, followed by a laser ablation to create the pattern. Then, the entire substrate is immersed into an aqueous solution containing amino-silane equipped Pd nanoparticles for the second modification.

Synthesis and Characterization of Novel β-Bis( N, N-diarylamino)-Substituted Porphyrin for Dye-Sensitized Solar Cells under 1 sun and Dim Light Conditions.

In this work, we have synthesized a novel porphyrin dye named SK7, which contains two N, N-diarylamino moieties at two β-positions as electron-donating units and one carboxy phenylethynyl moiety at the meso-position as an electron-withdrawing, anchoring group. This novel dye was tested for the application in dye-sensitized solar cells. The light-harvesting behavior of SK7 and YD2 was investigated using UV-vis absorption and density functional calculation.

Solvent-Dependent Adhesion Strength of Electroless Deposited Ni-P Layer on an Amino-Terminated Silane Compound-Modified Si Wafer.

Amino-terminated silane compound modification was wet-processed on a silicon wafer using four different solvents to investigate the property of the self-assembled monolayer (SAM) and its influence on the adhesion of electroless deposited nickel-phosphorus (Ni-P) films. Analyzed by various tools including dynamic light scattering, the atomic force microscope, X-ray photoelectron spectroscopy, inductively coupled plasma with mass spectroscopy, a proper link between the processing solvent and SAM quality is established. It is found that at least the chemical compatibility, the polarity, and the acidity of solvents can affect the final morphology of the resultant SAM.

Environmentally and Mechanically Stable Selenium 1D/2D Hybrid Structures for Broad-Range Photoresponse from Ultraviolet to Infrared Wavelengths.

Selenium (Se) is one of the potential candidates as photodetector because of its outstanding properties such as high photoconductivity (∼8 × 10 S cm), piezoelectricity, thermoelectricity, and nonlinear optical responses. Solution phase synthesis becomes an efficient way to produce Se, but a contamination issue that could deteriorate the electric characteristic of Se should be taken into account. In this work, a facile, controllable approach of synthesizing Se nanowires (NWs)/films via a plasma-assisted growth process was demonstrated at the low substrate temperature of 100 °C.

Structurally Simple and Easily Accessible Perylenes for Dye-Sensitized Solar Cells Applicable to Both 1 Sun and Dim-Light Environments.

The need for low-cost and highly efficient dyes for dye-sensitized solar cells under both the sunlight and dim light environments is growing. We have devised GJ-series push-pull organic dyes which require only four synthesis steps. These dyes feature a linear molecular structure of donor-perylene-ethynylene-arylcarboxylic acid, where donor represents N,N-diarylamino group and arylcarboxylic groups represent benzoic, thienocarboxylic, 2-cyano-3-phenylacrylic, 2-cyano-3-thienoacrylic, and 4-benzo[c][1,2,5]thiadiazol-4-yl-benzoic groups.

Manipulating the adhesion of electroless nickel-phosphorus film on silicon wafers by silane compound modification and rapid thermal annealing.

In this study, the effect of 3-2-(2-aminoethylamino) ethylamino propyl trimethoxysilane (ETAS) modification and post rapid thermal annealing (RTA) treatment on the adhesion of electroless plated nickel-phosphorus (ELP Ni-P) film on polyvinyl alcohol-capped palladium nanoclusters (PVA-Pd) catalyzed silicon wafers is systematically investigated. Characterized by pull-off adhesion, atomic force microscopy, X-ray spectroscopy and water contact angle, a time-dependent, three-staged ETAS grafting mechanism including islandish grafting, a self-assembly monolayer (SAM) and multi-layer grafting is proposed and this mechanism is well correlated to the pull-off adhesion of ELP Ni-P film. In the absence of RTA, the highest ELP Ni-P film adhesion occurs when ETAS modification approaches SAM, where insufficient or multi-layer ETAS grafting fails to provide satisfactory results.

Spiro-Phenylpyrazole/Fluorene as Hole-Transporting Material for Perovskite Solar Cells.

Spiro-OMeTAD with symmetric spiro-bifluorene unit has dominated the investigation of hole-transporting material (HTM) for efficient perovskite solar cells (PSCs) despite of its low intrinsic hole conductivity and instability. In this study, we designed and synthesized three asymmetric spiro-phenylpyrazole/fluorene base HTMs, namely: WY-1, WY-2 and WY-3. They exhibit excellent electrochemical properties and hole conductivities.

Performance Characterization of Dye-Sensitized Photovoltaics under Indoor Lighting.

Indoor utilization of emerging photovoltaics is promising; however, efficiency characterization under room lighting is challenging. We report the first round-robin interlaboratory study of performance measurement for dye-sensitized photovoltaics (cells and mini-modules) and one silicon solar cell under a fluorescent dim light. Among 15 research groups, the relative deviation in power conversion efficiency (PCE) of the samples reaches an unprecedented 152%.

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.

Electrodeposited Ultrathin TiO2 Blocking Layers for Efficient Perovskite Solar Cells.

In this study, the electrodeposition (ED) of ultrathin, compact TiO2 blocking layers (BLs) on fluorine-doped tin oxide (FTO) glass for perovskite solar cells (PSCs) is evaluated. This bottom-up method allows for controlling the morphology and thickness of TiO2 films by simply manipulating deposition conditions. Compared with BLs produced using the spin-coating (SC) method, BLs produced using ED exhibit satisfactory surface coverage, even with a film thickness of 29 nm.

Efficient perovskite solar cells fabricated using an aqueous lead nitrate precursor.

A novel, aqueous precursor system (Pb(NO3)2 + water) is developed to replace conventional (PbI2 + DMF) for fabricating methylammonium lead iodide (MAPbI3) perovskite solar cells (PSCs). When the morphology and surface coverage of the Pb(NO3)2 film was controlled during coating, a power conversion efficiency of 12.58% under standard conditions (AM1.

Ruthenium and osmium complexes that bear functional azolate chelates for dye-sensitized solar cells.

The preparation of sensitizers for dye-sensitized solar cells (DSSCs) represents an active area of research for both sustainability and renewable energy. Both Ru(II) and Os(II) metal sensitizers offer unique photophysical and electrochemical properties that arise from the intrinsic electronic properties, that is, the higher propensity to form the lower-energy metal-to-ligand charge-transfer (MLCT) transition, and their capability to support chelates with multiple carboxy groups, which serve as a bridge to the metal oxide and enable efficient injection of the photoelectron. Here we present an overview of the synthesis and testing of these metal sensitizers that bear functional azolate chelates (both pyrazolate and triazolate), which are capable of modifying the metal sensitizers in a systematic and beneficial manner.

A significant improvement in the electrocatalytic stability of N-doped graphene nanosheets used as a counter electrode for [Co(bpy)3](3+/2+) based porphyrin-sensitized solar cells.

A significant improvement in efficiency is achieved for porphyrin (YD2-o-C8) based dye-sensitized solar cells, coupled with [Co(bpy)3](3+/2+) mediator electrolyte. However, the poison of the counter electrode (CE) by the [Co(bpy)3](3+/2+) mediator remains a significant barrier to producing a reliable high-performance device. In this paper, nitrogen-doped graphene nanosheets (NG) are produced using a low-cost solution-based process and are used as the CE for [Co(bpy)3](3+/2+) based porphyrin-sensitized solar cells.

Eugenic metal-free sensitizers with double anchors for high performance dye-sensitized solar cells.

A series of new phenothiazine-based dyes (HL5-HL7) with double acceptors/anchors have been synthesized and used as the sensitizers for highly efficient dye-sensitized solar cells (DSSCs). Among them, the HL7-based cell exhibits the best efficiency of 8.32% exceeding the N719-based cell (7.

Layered double hydroxides as an effective additive in polymer gelled electrolyte based dye-sensitized solar cells.

Layered double hydroxides (LDH), a class of anionic clay materials, were developed as an effective additive for polymer gelled electrolytes for use in dye-sensitized solar cells (DSSC). Carbonate and chloride intercalated Zn-Al LDHs, ZnAl-CO3 LDH, and ZnAl-Cl LDH were prepared with coprecipitation methods. The addition of the two LDHs significantly improved, in terms of power conversion efficiency (PCE), over the plain poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) gelled electrolyte and competed favorably with the liquid electrolyte based DSSCs, 8.

High electrocatalytic and wettable nitrogen-doped microwave-exfoliated graphene nanosheets as counter electrode for dye-sensitized solar cells.

In this paper, high electrocatalytic and wettable nitrogen-doped microwave-exfoliated graphene (N-MEG) nanosheets are used as Pt-free counter electrode (CE) for dye-sensitized solar cells (DSSCs). A low cost solution-based process is developed by using cyanamide (NH2 CN) at room temperature and normal pressure. The pyrrolic and pyridinic N atoms are doped into the carbon conjugated lattice to enhance electrocatalytic activity.