The rapid development of organic electrochemical transistor (OECTs)‐based circuits brings new opportunities for next‐generation integrated bioelectronics. The all‐polymer bulk‐heterojunction (BHJ) offers an attractive, inexpensive alternative to achieve efficient ambipolar OECTs, and building blocks of logic circuits constructed from them, but have not been investigated to date. Here, the first all‐polymer BHJ‐based OECTs are reported, consisting of a blend of new p‐type ladder conjugated polymer and a state‐of‐the‐art n‐type ladder polymer. The whole ladder‐type polymer BHJ also proves that side chains are not necessary for good ion transport. Instead, the polymer nanostructures play a critical role in the ion penetration and transportation and thus in the device performance. It also provides a facile strategy and simplifies the fabrication process, forgoing the need to pattern multiple active layers. In addition, the development of complementary metal–oxide–semiconductor (CMOS)‐like OECTs allows the pursuit of advanced functional logic circuitry, including inverters and NAND gates, as well as for amplifying electrophysiology signals. This work opens a new approach to the design of new materials for OECTs and will contribute to the development of organic heterojunctions for ambipolar OECTs toward high‐performing logic circuits.

Defect management strategies are vital for enhancing the performance of perovskite-based optoelectronic devices, such as perovskite-based light-emitting diodes (PeLEDs). As additives can fucntion both as acrystallization modifier and/or defect passivator, a thorough study on the roles of additives is essential, especially for blue emissive Pe-LEDs, where the emission is strictly controlled by the n-domain distribution of the Ruddlesden−Popper (RP, L 2 A n−1 Pb n X 3n+1 , where L refers to a bulky cation, while A and X are monovalent cation, and halide anion, respectively) perovskite films. Of the various additives that are available, octyl phosphonic acid (OPA) is of immense interest because of its ability to bind with uncoordinated Pb 2+ ( notorious for nonradiative recombination) and therefore passivates them. Here, with the help of various spectroscopic techniques, such as X-ray photon-spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), and photoluminescence quantum yield (PLQY) measurements, we demonstrate the capability of OPA to bind and passivate unpaired Pb 2+ defect sites. Modification to crystallization promoting higher n-domain formation is also observed from steady-state and transient absorption (TA) measurements. With OPA treatment, both the PLQY and EQE of the corresponding PeLED showed improvements up to 53% and 3.7% at peak emission wavelength of 485 nm, respectively.

Recently it is discovered that molecular junctions can be pushed into theMarcus Inverted region of charge transport, but it is unclear which factors are important. This paper shows that the mechanism of charge transport across molecular wires can be switched between the normal and Marcus Inverted regions by fine-tuning the molecule-electrode coupling strength and the tunneling distance across oligophenylene ethynylene (OPE) wire terminated with ferrocene (Fc) abbreviated as S-OPE n Fc (n = 1-3). Coherent tunneling dominates the mechanism of charge transport in junctions with short molecules (n = 1), but for n = 2 or 3 redox reactions become important. By weakening the molecule-electrode interaction by interrupted conjugation, S-CH 2 -OPE n Fc, intramolecular orbital gating can occur pushing the junctions completely into the Marcus Inverted region. These results indicated that weak molecule-electrode coupling is important to push junctions into the Marcus Inverted Region.

Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) based organic electrochemical transistors (OECTs) have proven to be one of the most versatile platforms for various applications including bioelectronics, neuromorphic computing and soft robotics. The use...

Electrocatalytic water splitting has recently surfaced as a promising method by transforming them into hydrogen fuel. [2] The bottleneck in the development of electrochemical water splitting technology is the oxygen evolution reaction (OER), which is the half reaction at the anode. [3] OER has very sluggish kinetics because it is a four proton-electron transfer process. [4] It is also a vital half-reaction for rechargeable metal-air batteries. [5] Therefore, efficient electrocatalysts are required to overcome the high OER overpotential. Currently, both RuO 2 and IrO 2 are regarded as the state-of-theart electrocatalysts for OER. [6][7][8] However, both of them show poor dissolution resistance under high anodic potential. [9,10] Moreover, their high price and scarcity make it vital to develop cost-effective, highly active, and durable electrocatalysts for OER. [11] Nanomaterial electrocatalysts are generally more efficient than their bulk counterparts due to larger specific surface areas and higher mass activities. Therefore, electrocatalysts with smaller size are normally desired for improved electrocatalytic performance. [12] For example, reducing the size of Cu nanoparticles can significantly increase its catalytic activity because of the increased low-coordination sites acting as active sites. [13] Likewise, size-dependent electrocatalytic activity has also been observed for Au nanoparticles. [14] However, it is still challenging Developing low-cost and efficient oxygen evolution electrocatalysts is key to decarbonization. A facile, surfactant-free, and gram-level biomass-assisted fast heating and cooling synthesis method is reported for synthesizing a series of carbon-encapsulated dense and uniform FeNi nanoalloys with a single-phase face-centered-cubic solid-solution crystalline structure and an average particle size of sub-5 nm. This method also enables precise control of both size and composition. Electrochemical measurements show that among Fe x Ni (1−x) nanoalloys, Fe 0.5 Ni 0.5 has the best performance. Density functional theory calculations support the experimental findings and reveal that the optimally positioned d-band center of O-covered Fe 0.5 Ni 0.5 renders a half-filled antibonding state, resulting in moderate binding energies of key reaction intermediates. By increasing the total metal content from 25 to 60 wt%, the 60% Fe 0.5 Ni 0.5 /40% C shows an extraordinarily low overpotential of 219 mV at 10 mA cm −2 with a small Tafel slope of 23.2 mV dec −1 for the oxygen evolution reaction, which are much lower than most other FeNi-based electrocatalysts and even the state-of-the-art RuO 2 . It also shows robust durability in an alkaline environment for at least 50 h. The gram-level fast heating and cooling synthesis method is extendable to a wide range of binary, ternary, quaternary nanoalloys, as well as quinary and denary high-entropy-alloy nanoparticles.