Novel earth-abundant metal sulfate-containing high entropy sulfides, FeNiCo-CrXS 2 (where X = Mn, Cu, Zn, or Al), are synthesized via a two-step solvothermal method. It is shown that sulfate-containing FeNiCoCrMnS 2 exhibits superior oxygen evolution reaction (OER) activity with an exceptionally low overpotential of 199, 246, 285, and 308 mV at current densities of 10, 100, 500, and 1000 mA cm -2 , respectively, and surpassing its unary-, binary-, ternary-, and quaternary-metal counterparts. The electrocatalyst yields exceptional stability after 12 000 cycles and 55 h of durability even at a high current density of 500 mA cm -2 . Various in situ and ex situ analyses are used to investigate the self-reconstruction of the sulfides during the OER for the first time. The resulting metal (oxy)hydroxide is believed to be the true active center for OER. The remaining sulfate also contributes to the catalytic activity. Density function theory calculation is in good agreement with the experimental result. The extraordinary OER performance of the high entropy sulfide brings a great opportunity for desirable catalyst design for practical applications.

Titanium (Ti)-based implants are broadly applied in the medical field, but their related infections can lead to implant failure. Photo-irradiation of metal materials to generate antimicrobial agents, an alternative to antibiotics, is a promising method to reduce bacterial infection and antibiotic usage. It is therefore important to understand how bacterial pathogens respond to Ti surfaces. Here, Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus, the most prevalent pathogens linked to healthcare-associated infections, were used as model strains. Two different kinds of Ti surfaces respectively stored in dry condition and 0.9 % NaCl solution were applied. Upon UV irradiation and in the absence of bacteria, both tested surfaces exhibited similar bactericidal activity, even though the surfaces stored in 0.9 % NaCl solution generated a slightly higher level of reactive oxygen species (ROS). Interestingly, P. aeruginosa and S. aureus responded to the irradiated Ti surfaces differently regarding interaction time: the number of viable P. aeruginosa was reduced up to 90 % after 30 min interaction with the treated surfaces compared to the untreated ones, but this reduction is lessened to 69 %-81 % after 240 min. By contrast, UV treatment of surfaces did not impact the viability of S. aureus after 30 min interaction, however, led to more than 99 % reduction after 240 min incubation. These results provide first experimental evidence that Gram negative and positive bacterial species respond to ROS with different inactivation kinetics. This work also demonstrated that treatment with photo-irradiation in the absence of bacteria conferred Ti surfaces with efficient bactericidal activity.

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With increasing demand of sustainable energy, hydrogen as a recyclable and green energy resource draws a lot of attention. Optical spintronics combining the spin photoelectron thereby distinct itself as the...

A photomemory based on a ZTO/Au NP heterostructure is revealed. It exhibits a broad spectral response and great retention to visible light due to the charge transfer at the ZTO/Au NP interface and surface plasmon resonance (SPR) of Au NPs.