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The BCN-heterocyclic B–N chain compounds, the sodium and potassium salts of 3and 4anions (Na3, Na4, and K4), were synthesized by reactions of ethane 1,2-diamineborane (BH3NH2CH2CH2NH2BH3, 1) and propane 1,2-diamineborane (BH3NH2CH2CH2CH2NH2BH3, 2) with MH (M = Na and K). Then, the neutral B–N chain compounds 5and 6were prepared with dehydrogenation of [NH4]3and [NH4]4, formed by metathesis reactions of Na3and Na4with NH4Cl or NH4SCN, respectively. Compounds 7and 8, analog 5, were also prepared using pyridine and 4-methoxypyridine instead of NH3in 5. These synthesized compounds were characterized spectroscopically, and the singe-crystal structures of the Na3·18-crown-6 and K4·18-crown-6 adducts were determined. Furthermore, the reactions of Na3and Na4with cationic B–N chain compounds, [NH3BH2NH3]Cl and [NH3BH2NH2BH2NH3]Cl, could not form longer BCN-heterocyclic B–N chain. The solubility of metal hydrides, the ability for proton abstracting, the basicity of Lewis bases, and the chelate effect may influence these reactions even though the reaction mechanism is not fully understood.

Recent research has attracted considerable attention toward N-heterocyclic carbene-coordinated boranes (NHC-borane) and their B-substituted derivatives because of their unique characteristics. In the present work, we focused on the syntheses, structures, and reactivities of such types of amine complexes, [NHC·BH2NH3]X ((NHC = IPr (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and IMe (1,3-dimethylimidazol-2-ylidene); X = Cl, I, OTf). We have developed a synthetic method to access NHC·BH2NH2through the reaction of NaH with [IPr·BH2NH3]I, which was synthesized by the reaction of IPr·BH2I with NH3. As a Lewis base, NHC·BH2NH2could further react with HCl or HOTf to produce the corresponding salts of [IPr·BH2NH3]+. IPr·BH2NH2BH2X (X = Cl, I) were synthesized by the reaction of HCl/I2with IPr·BH2NH2BH3and then converted to [IPr·BH2NH2BH2·IPr]X (X = Cl, I) by reacting with IPr. The IMe-coordinated boranes reacted quite similarly. The preliminary results revealed that the introduction of the NHC molecule has a considerable impact on the solubility and reactivities of aminoboranes.

Polyhedral boranes are a class of well-known boron molecular clusters with unique physical and chemical properties, and great efforts have been made in the past decades to find more effective synthetic methods. However, the established synthetic methods suffer from low efficiency and low selectivity because the mechanism of the B–H bond condensation reaction, critical for the synthesis of the polyhedral boranes, is not well understood. Here we report highly selective and efficient synthetic methods of the salts of the tetradecahydridoundecaborate (1–) (B11H14−) and dodecahydrido-dodecaborates (2–) (B12H122−) anions by employing commercially available and inexpensive starting materials. Both theoretical and experimental investigations are carried out to elucidate the reaction mechanisms. We have found that the nature of the B–H bond condensation is the dihydrogen bonding interaction in which the positively charged hydrogens (bridged hydrogens) play a crucial role. The current study has not only led to more effective and selective synthetic methods for B11H14−and B12H122−but also unveiled the nature of the B–H bond condensation and the general formation mechanisms of polyhedral boranes. This finding will facilitate the development of more effective synthetic methods for polyhedral boranes and spur their wide application.

The design, synthesis, and applications of new boranes are eternal topics in boron chemistry. A new bis(borane)alkanethiolate salt, K[BH3S(CH3)BH3], was synthesized in high yield by the reaction of K with (CH3)2S·BH3at room temperature. The formation mechanism was elucidated based on experimental and theoretical studies. The single-crystal structure of the K[BH3S(CH3)BH3]·18-crown-6 adduct was determined in which the B–S–B bonding information of K[BH3S(CH3)BH3] was illustrated for the first time. Using K[BH3S(CH3)BH3] as a starting material, KB3H8was successfully synthesized.

All-solid-state potassium batteries are promising candidates in the fields of large-scale energy storage owing to their intrinsic safety, stability, and cost-effectiveness. However, a suitable solid-state electrolyte with high ionic conductivity and favorable interfacial stability is a major challenge for the design and development of these batteries. Herein, we report the synthesis of new KB3H8·nNH3B3H7(n= 0.5 and 1) complexes to develop suitable solid-state K-ion conductors for batteries. Both the complexes undergo a reversible phase transition below the thermal decomposition temperature. The optimal KB3H8·NH3B3H7delivers a solid-state K-ion conductivity of 1.3 × 10–4S cm–1at 55 °C with an activation energy of 0.44 eV after a transition from a monoclinic to an orthorhombic phase, which is the highest value of K borohydrides reported to date and places KB3H8·NH3B3H7among the leading solid-state K-ion conductors. Moreover, KB3H8·NH3B3H7reveals a K-ion transference number of nearly 0.93, an electrochemical stability window of 1.2 to 3.5 V vs K+/K, a good capability of K dendrite suppression, and a remarkable stability against the K metal anode due to the formation of the stable interface. These performances make KB3H8·NH3B3H7a promising electrolyte for all-solid-state potassium batteries.

The High-energy Fragment Separator (HFRS), which is currently under construction, is a leading international radioactive beam device. Multiple sets of position-sensitive twin time projection chamber (TPC) detectors are distributed on HFRS for particle identification and beam monitoring. The twin TPCs’ readout electronics system operates in a trigger-less mode due to its high counting rate, leading to a challenge of handling large amounts of data. To address this problem, we introduced an event-building algorithm. This algorithm employs a hierarchical processing strategy to compress data during transmission and aggregation. In addition, it reconstructs twin TPCs’ events online and stores only the reconstructed particle information, which significantly reduces the burden on data transmission and storage resources. Simulation studies demonstrated that the algorithm accurately matches twin TPCs’ events and reduces more than 98% of the data volume at a counting rate of 500 kHz/channel.

Improved methods for the synthesis of KB3H8, NH3B3H7, and N-alkyl analogues of NH3B3H7have been developed based on previous works. KB3H8was synthesized by the reaction of metallic potassium (K) with borane dimethyl sulfide ((CH3)2S·BH3) with high yield and atom-economy. In the preparation of NH3B3H7and its N-alkyl analogues, KB3H8served as a starting material and was converted to THF·B3H7first through reactions with HCl diethyl ether solution or oxidation agent CoCl2. Then, the formed THF·B3H7in situ reacted with the corresponding ammonia or amines to form the amine borane final products. This work paves an alternative way for preparing organic–inorganic hybrid materials containing B, N, and C atoms.

The reactions of sodium amidoborane (NaNH2BH3) with NiBr2have been investigated, and the results showed that black precipitate 1including the NiBNHxcomposites could be obtained. From the aqueous solution of the precipitate 1, the hydrolysis product Ni–B (2) was isolated and characterized. Both the in situ formed precipitate 1and the hydrolysis product 2can catalyze the formation of Na[BH3(NH2BH2)2H]. CoCl2showed comparable performance with NiBr2. Based on these results, a facile method for the synthesis of Na[BH3(NH2BH2)2H] has been developed. This work provides insights into studying experimental methods for the synthesis of long B/N chain complexes and developing boron and nitrogen chemistry.

A digital regulator architecture implemented in FPGA is described which is used in the accelerator power supply. To save the delay time, the device is based on combinational circuit and special data format. The multiplier uses the partial products generated by modified Booth algorithm, Carry look-ahead adder and Wallace tree. The regulator is written in Verilog, and is synthesized into FPGA. The synthesis results shows that the proposed regulator can run 200MHZ clock rate in FPGA EP3C25F256 and the whole feedback time is as short as 3 clock periods.