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The mimicking of both homosynaptic and heterosynaptic plasticity using a high-performance synaptic device is important for developing human-brain-like neuromorphic computing systems to overcome the ever-increasing challenges caused by the conventional von Neumann architecture. However, the commonly used synaptic devices (e.g., memristors and transistors) require an extra modulate terminal to mimic heterosynaptic plasticity, and their capability of synaptic plasticity simulation is limited by the low weight adjustability. In this study, a WSe2 -based memtransistor for mimicking both homosynaptic and heterosynaptic plasticity is fabricated. By applying spikes on either the drain or gate terminal, the memtransistor can mimic common homosynaptic plasticity, including spiking rate dependent plasticity, paired pulse facilitation/depression, synaptic potentiation/depression, and filtering. Benefitting from the multi-terminal input and high adjustability, the resistance state number and linearity of the memtransistor can be improved by optimizing the conditions of the two inputs. Moreover, the device can successfully mimic heterosynaptic plasticity without introducing an extra terminal and can simultaneously offer versatile reconfigurability of excitatory and inhibitory plasticity. These highly adjustable and reconfigurable characteristics offer memtransistors more freedom of choice for tuning synaptic weight, optimizing circuit design, and building artificial neuromorphic computing systems.

A dinuclear ruthenium complex [RuII(NCNHCO)(pic)2]22+ (2) was firstly prepared and characterized spectroscopically and electrochemically. Instead of the conventional ligand exchange, complex 2 dissociates in-situ to afford two single-site Ru aqua complexes, [RuII(OH2)(NCNHCO)(pic)2]+, which mediates water oxidation through proton-coupled electron transfer events. In electrokinetic studies, complex 2 demonstrated a TOF of 150.3 s-1 comparable to those state-of-the-art catalysts at neutral conditions. TONs of 2173 and 217 were attained in chemical and photochemical water oxidation when 2 was used as a catalyst, exhibiting good stability. Notably, a TOF of 1.3 s-1 was achieved at CAN-driven water oxidation, which outper-formed most of the reported single-site Ru complexes, indicating that complex 2 is one of most active water oxidation catalysts (WOCs) to date. The unique coordination configuration and outstanding catalytic perfor-mance of complex 2 might shed light on the design of novel molecular WOCs.

A series of high-quality M2(BDC)2(DABCO) metal-organic frameworks (abbreviated as M-DABCO; M=Zn, Co, Ni, Cu; BDC=1,4-benzene dicarboxylate; DABCO=1,4-diazabicyclo[2.2.2]octane), were synthesized by using a solvothermal (SV) method, and their catalytic activity for the cycloaddition of CO2 to epoxides in the absence of a co-catalyst or solvent was demonstrated. Of these metal-organic frameworks (MOFs), Zn-DABCO exhibited very high activity and nearly complete selectivity under moderate reaction conditions. The other members of this MOF series (Co-DABCO, Ni-DABCO, and Cu-DABCO) displayed lower activity in the given sequence. Samples of Zn-DABCO, Co-DABCO, and Ni-DABCO were recycled at least three times without a noticeable loss in catalytic activity. The reaction mechanism can be attributed to structural defects along with the acid-base bifunctional characteristics of these MOFs. Moreover, we illustrate that the synthetic method of M-DABCO influences the yield of the reaction. In addition to the SV method, Zn-DABCO was synthesized by using spray drying due to its industrial attractiveness. It was found that the synthesis procedure clearly influenced the crystal growth and thus the physicochemical properties, such as surface area, pore volume, and gas adsorption, which in turn affected the catalytic performance. The results clarified that although different synthetic methods can produce isostructural MOFs, the application of MOFs, especially as catalysts, strongly depends on the crystal morphology and textural properties and, therefore, on the synthesis method.

Biomethane is one of the biofuel sources produced from biogas which is an important source of renewable energy. Since it is an alternative and clean energy source, its implementation as fuel source applying established energy infrastructure is an attractive opportunity. However, biogas as a source of biomethane contains undesirable compounds, e.g., H2S, NH3, siloxanes, water, etc. and needs to be decontaminated before usage. Biogas cleaning technologies are presented from a material point of view along with their property modifications. A brief discussion of materials applied in technologies with a particular emphasis on biogas cleaning is followed by the alternative properties and possibilities of liquid and solid adsorbents as well as chemical reactions used for biogas cleaning to produce biomethane suitable as fuel source to replace or reduce fossil fuel consumption.

Phototunable biomaterial-based resistive memory devices and understanding of their underlying switching mechanisms may pave a way toward new paradigm of smart and green electronics. Here, resistive switching behavior of photonic biomemory based on a novel structure of metal anode/carbon dots (CDs)-silk protein/indium tin oxide is systematically investigated, with Al, Au, and Ag anodes as case studies. The charge trapping/detrapping and metal filaments formation/rupture are observed by in situ Kelvin probe force microscopy investigations and scanning electron microscopy and energy-dispersive spectroscopy microanalysis, which demonstrates that the resistive switching behavior of Al, Au anode-based device are related to the space-charge-limited-conduction, while electrochemical metallization is the main mechanism for resistive transitions of Ag anode-based devices. Incorporation of CDs with light-adjustable charge trapping capacity is found to be responsible for phototunable resistive switching properties of CDs-based resistive random access memory by performing the ultraviolet light illumination studies on as-fabricated devices. The synergistic effect of photovoltaics and photogating can effectively enhance the internal electrical field to reduce the switching voltage. This demonstration provides a practical route for next-generation biocompatible electronics.