The development of nontoxic and stable all-inorganic perovskite nanocrystals (NCs) represents a major challenge to unlock widely practical applications in photoelectric fields.

Exploiting robust and durable electrocatalysts for water splitting remains a challenge due to its sluggish oxidative half reaction. Herein, we demonstrate a facile and novel strategy to prepare an amorphous N-doped cobalt borophosphate catalyst through the calcination of zeolite-type cobalt borophosphate precursor with NH3 molecule. The as-prepared material displays robust catalytic activity and high stability within 18 h for the oxygen evolution reaction (OER) in 1.0 M KOH, e.g., an overpotential of 276 mV at 10 mA cm–2 (η @ 10 mA cm–2) and a Tafel slope of 55.8 mV dec–1, which is comparable to that of the benchmark IrO2 electrocatalyst. Its excellent catalytic activity should be ascribed to the N-dopant which could accelerate the electron transfer by tuning the electronic structure of this borophosphate; moreover, this amorphous phase with zeolite-like porous structures could increase its active site density and improve the electron and mass transport as well as facilitating gas release. Our study not only discovers a high-efficiency OER electrocatalyst but also provides a facile and practical pathway to develop promising electrocatalysts for water splitting.

Antioxidative activities were found in the culture supernatant of Bacillus licheniformis OPL-007 using shrimp head waste (SHW) as the sole carbon and nitrogen source. After optimizing fermentation conditions, some bio-active substances were determined from the broth. The contents of total phenols, polysaccharides, reducing sugars, free amino acids, and organic acids were 888.80, 402.74, 85.88, 2,061.79, and 5,426.74 mg/l, respectively. Moreover, the fermentation liquid was found rich in eight essential amino acids and non-protein amino acids. The antioxidant activity of the culture supernatant, in terms of the scavenging activity of DPPH radicals, reducing power, and metal chelating ability, was monitored, and the fermentation liquid showed a strong antioxidant capacity. The results indicate that bio-deproteinization of SHW by B. licheniformis OPL-007 can increase its antioxidant activity, and SHW has the potential application in the production of functional foods.

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