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The copolymerization of carbonyl sulfide (COS) with epoxides has been developed to be a facile method to synthesize well-defined sulfur-containing polymers. This work describes the steric effect of tertiary amines on the copolymerization of COS with propylene oxide (PO) via a zwitterionic approach, using triethyl borane (TEB) accompanied by various tertiary amines. N,N-Dimethylcyclohexylamine accompanied by TEB (1/1) showed an exceedingly high turnover frequency of up to 69 800 h−1 and a copolymer selectivity of up to >99% for organocatalytic COS/PO copolymerization at 60 °C under solvent-free conditions. The obtained poly(propylene monothiocarbonate)s (PPMTC)s have fully alternating sequences, regioregularity of >99% tail-to-head (T–H) content, and high-number average molecular weights of up to 221.8 kg mol−1 and narrow dispersities (1.1–1.3) within 1 min. We disclosed that tertiary amines (pKa values range from 8.19 to 10.80) with less steric hindrance exhibited higher catalytic activity for COS/PO copolymerization.

Cubic MnSe2 microcubes are introduced into sulfur cathodes to prevent the shuttle effect of lithium polysulfide through binding with polysulfide via the strong interaction between Se and S, thus alleviate the shuttle effect significantly. Improved cycle performance and rate capability are achieved. This work offers a new strategy to develop high-performance lithium–sulfur batteries.

Constructing a befitting structure for efficient charge separation and transport is highly required for photocatalytic water splitting reactions to generate hydrogen (H2). Herein, we successfully integrated a defective TiO2/MoP heterojunction with highly conductive carbon cloth (CC), for constructing a panel reactor with charge transfer channels to boost H2 evolution. As expected, the behavior of photogenerated charge carriers is effectively steered, resulting in high-efficiency charge migration and separation, and consequently improving photocatalytic activity. The optimal TiO2/MoP/CC exhibits a H2 generation rate of 14.7 μmol h−1 cm−2, up to 19 times higher than that of TiO2/CC. Our work can open up ways to optimize the photocatalytic performance by developing novel non-powder-based photocatalyst systems with good stability and recyclability.

Studies of transition metal dichalcogenides (TMDs) can be traced back to the 1970s but they have been abandoned for a while due to the fire hazard of lithium metal batteries. Herein, a new layered material, CrSSe, is reported, whose intercalative capacity can achieve 190 mA h g−1 with charges all compensated by anionic S and Se. Fascinating performances of half-cells are also presented, with a capacity retention rate of 81.5% upon 1000 cycles at 20C and a high output of 101.7 mA h g−1 even at 200C. In addition, an ideal way to build a type of full battery without lithium anodes for CrSSe is also displayed; a Li3N film was synthesized on the electrode surface as a lithium source. Overall, the discovery of CrSSe enriches the chemistry of TMDs and the application in full batteries opens up opportunities for enabling lithium-free cathodes to be widely utilized in practical applications.

Designing an architecture with the ability to temporarily capture one kind of charge carrier has a critical role to play in enhancing the performance of photocatalytic reactions. Here, we report that SrTiO3 nanofibers that have been treated with a brief method of H2 calcination in an H2/N2 atmosphere (denoted as STO-NH) form oxygen vacancies (OVs) and achieve significant improvement in performance in photocatalytic H2 production without the presence of cocatalysts. These OVs can trap photogenerated electrons, which inhibits the recombination of electrons and holes in both the surface and the bulk, thus improving the photocatalytic decomposition of water. Moreover, the concentration of surface OVs in STO-NH presents volcanic characteristics: the increase with rise in hydrogenation temperature, with a consequent increase in catalytic activity, indicates well-controlled formation of OVs. The existence and concentration of the OVs in STO-NH photocatalysts are investigated qualitatively through electron paramagnetic resonance, high-resolution transmission electron microscope and photoluminescence emission spectra. A reasonable photocatalytic mechanism is proposed that we expect to be able to provide significant guidance for future study.

A cation-disordered Li-excess cathode material on the binary system xLi3NbO4–(1 − x)LiCrO2 (x = 0.43) has been successfully prepared by mechanical milling, and delivers a high reversible capacity of ∼362 mA h g−1, which originates from a highly reversible Cr3+/Cr6+ three-electron redox reaction with electrochemically inactive niobium ions.

Si/C composites are considered as the most promising anode materials for next-generation lithium-ion batteries (LIBs) due to their high specific capacity and low cost. However, the commercialized Si/C composites cannot maintain a Si content over 10 wt% for sustaining an acceptable cycle life. To achieve long-term cycle stability for Si/C composites with high Si content is still very challenging. Here, we report a rationally designed double-morphology Si/graphene (DMSiG) composite with a high Si content of 78 wt%, and prove its feasibility as a high performance anode material for LIBs. DMSiG composes of Si quantum-dot decorated graphene and mesoporous Si spheres with a complementary hierarchical structure. The graphene framework enhances the electronic conductivity, alleviates the aggregation of mesoporous Si spheres and provides space and flexibility to buffer the volume change during cycling. Mesoporous Si spheres contribute to a large reversible capacity and support the hierarchical architecture of DMSiG. The Si quantum-dots help to build firm connections between graphene and mesoporous Si spheres to avoid their separation during cycling. Coupling these features together, the DMSiG anode delivers a high reversible capacity of 1318 mA h g-1 at a current density of 500 mA g-1 and 684 mA h g-1 at 2000 mA g-1.