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Herein, ultra-low amount Pt is uniformly deposited on the surface of CoFe nanoparticles (NPs) embedded nitrogen-doped carbon nanotubes which are grown directionally on the surface of carbon fiber cloth (Pt–CoFe@NCNT/CFC) using the direct current plasma magnetron sputtering (DC-PMS) technique. The designed electrode exhibits excellent trifunctional catalytic activities towards oxygen reduction reaction (ORR) (in 0.1 M KOH, E 1/2 = 0.807 V; in 0.5 M H 2 SO 4 , E 1/2 = 0.723 V), hydrogen evolution reaction (HER) (in 1 M KOH, η 10 = 17 mV and η 100 = 93 mV; in 0.5 M H 2 SO 4 , η 10 = 42 mV and η 100 = 100.5 mV) and methanol oxidation reaction (MOR) (in 0.5 M H 2 SO 4 + 0.5 M CH 3 OH, peak current density reaches 115 mA mg−1 Pt @1.116 V). It is verified that the DC-PMS technique can greatly improve the utilization efficiency of Pt, so as to reduce the dosage of Pt, and shows better catalytic performance and excellent stability than the commercial Pt/C catalysts. The rich hierarchical heterostructures of the designed electrode can provide more non-noble metal active sites, so as to enhance the catalytic activity and further cut down the consumption of noble metals. Impressively, Pt–CoFe@NCNT/CFC electrode assembled direct methanol fuel cell achieved a remarkable maximum power density of 73.41 mW cm−2 and shows excellent stability. Pt nanoclusters are deposited on the surface of CoFe metal embedded nitrogen-doped carbon nanotubes by DC plasma magnetron sputtering technology, and the designed electrode exhibits excellent trifunctional catalytic activities towards ORR/MOR/HER. [Display omitted] • Pt is uniformly deposited on the surface of CoFe@NCNT/CFC using DC-PMS technique. • Abundant non-noble metal active sites are beneficial to reduce the consumption of Pt. • It provides abundant rivet points for the efficient deposition of Pt. • It shows stable and efficient ORR/MOR/HER multi-functional catalytic performance. • The assembled DMFC exhibits good performance and excellent stability. [ABSTRACT FROM AUTHOR]

A facile hydrothermal and freeze‐drying approach was employed to prepare N, B co‐doped graphene gel (N/BGR). Positively charged [BMIm][BF4] ionic liquid as N/B source and negatively charged graphene oxide (GO) as graphene precursor are capable of combining and self‐assembly by electrostatic force. The high doped concentrations of N and B elements are 8.16 at% and 6.31 at% (total 14.47 at%). The N/BGR was fabricated as electrode material in the three‐electrode system. The as‐prepared N/BGR‐2 electrode could achieve a specific capacitance of 133.6 F/g at 0.5 A/g. The N/BGR electrode presented enhanced capacitance performance. Compared with the specific capacitance of pure GR at the same current density of 0.5 A/g, the specific capacitances of N/BGR‐2 and N/BGR‐1 have increased by 68.5 % and 49.4 %. The enhanced capacitance of N and B co‐doped graphene could be attributed to the promotion of rapid electron migration and charge transfer and production of redox active sites that provide pseudocapacitance. In addition, N/BGR‐2 electrode exhibits good cycling durability with the capacity retention of 93.2 %% after 1500 cycles at a high current density of 10 A/g. Those provide a high co‐doped content fabrication strategy for high‐performance supercapacitors carbon‐based electrode materials. [ABSTRACT FROM AUTHOR]

Visible (VIS) and near-infrared (NIR) mechanoluminescence (ML) materials have been developed rapidly for use in energy conversion, biological applications and mechanical sensing. The realization of visible and NIR ML in single host materials meets the dual requirements of visualization and anti-interference for high-precision mechanical sensing. In this work, Mn2+ single-doped magnesium aluminate spinel MgAl2O4 with excellent ML performance was studied in detail. Bright, visible green and NIR ML were achieved under mechanical stimulation, and the ratio between visible and NIR ML intensity can be regulated by manipulating the doping concentration of Mn2+. The generation of ML without additional pre-irradiation proved that the self-powered ML phenomenon was independent of trap. The functional relationship between mechanical parameters and ML intensity indicated that the doped spinel can be used for visualization, anti-interference and non-contact mechanical sensing. In addition, the NIR ML of MgAl2O4:Mn2+, centered at 835 nm, is located in the first NIR window (NIR-I, 650–950 nm), which effectively penetrates living tissue such as skin, fat, and lean meat, respectively, showing that it has potential applications in in vivo optical imaging. [ABSTRACT FROM AUTHOR]

Herein, a bimetallic sulfide Fe0.4Co0.6S2@NC nanobox was prepared via a simple two-step synthetic route. The N-doped carbon coated hollow nanobox was derived from a Prussian blue analogue (PBA) and applied for an SIB anode. As expected, it exhibits a high capacity (486.6 mA h g−1 at 0.1 A g−1) and displays an excellent cycling stability (230 mA h g−1 at 10 A g−1 after 900 cycles). [ABSTRACT FROM AUTHOR]

In contrast to the conventional MX2 with mirror symmetry, Janus MXY (M = Mo, W; X = S, Se; Y= S, Se; X≠Y) breaks the mirror symmetry along the direction perpendicular to the two-dimensional material plane, reducing the overall symmetry. The electronegativity differences between X and Y produce an intrinsic electric dipole and cause a built-in electric field, resulting in strong spin-orbit coupling (SOC). Using first-principles density functional theory (DFT) calculations, we investigated the spin-orbit coupling induced by changing the doping ratio x on the surface of the monolayer (S x Se 1- x)MSe. The band structures of the monolayer (S x Se 1- x)MSe with different S/Se ratios were investigated with and without SOC. In addition to Zeeman-type spin splitting and valley polarisation at the K point, Rashba-type spin splitting around the point Γ was observed. Moreover, Rashba parameters α R of monolayer (S x Se 1- x)MSe can be tuned by changing the doping ratio x of the surface. [ABSTRACT FROM AUTHOR]