High-performance light-driven heterogeneous CO2 catalysis with near-unity selectivity on metal phosphides

Akin to single-site homogeneous catalysis, a long sought-after goal is to achieve reaction site precision in heterogeneous catalysis for chemical control over patterns of activity, selectivity and stability. Herein, we report on metal phosphides as a class of material capable of realizing these attributes and unlock their potential in solar-driven CO2 hydrogenation. Selected as an archetype, Ni12P5 affords a structure based upon highly dispersed nickel nanoclusters integrated into a phosphorus lattice that harvest light intensely across the entire solar spectral range. Motivated by its panchromatic absorption and unique linearly bonded nickel-carbonyl-dominated reaction route, Ni12P5 is found to be a photothermal catalyst for the reverse water gas shift reaction, offering a CO production rate of 960 ± 12 mmol gcat−1 h−1, near 100% selectivity and long-term stability. Successful extension of this idea to Co2P analogs implies that metal phosphide materials are poised as a universal platform for high-rate and highly selective photothermal CO2 catalysis.

Unsaturated binuclear homoleptic nickel carbonyl anions Ni2(CO)n− (n = 4–6) featuring double three-center two-electron Ni–C–Ni bonds

The two nickel atoms in the Ni2(CO)n− (n = 4–6) complexes are joined by two bridging carbonyl ligands via the sharing three-center two-electron Ni–C–Ni bond in turn to achieve the (16,16), (16,18), and eventually the favored (18,18) configurations.

IMPACT OF WORKING CONDITIONS ON THE HEALTH OF WORKERS EMPLOYED IN NICKEL CARBONYL REFINING

A method of nickel carbonyl refining is known to be associated with an increased risk of acute and chronic nickel tetracarbonyl (TKN) intoxication. The purpose of the study was to examine the features of the influence of working conditions and, above all, TKN aerosols on the development of general and occupational pathology in nickel carbonyl production workers. In today’s nickel carbonyl refining TK is established to have a predominant influence on the development of chronic bronchopulmonary diseases, the most common of which are chronic bronchitis (11.5% of employees) and toxic pulmonary fibrosis (11.2% of employees). In the last 10 years there were no recorded cases of previously observed extra pulmonary diseases associated with toxic TKN effects (cardiomyopathy, hepatitis, encephalopathy). However, the employees engaged in nickel carbonyl refining continue to experience an increased risk of developing occupational diseases as compared to both electrolytic nickel production workers (RR = 2.13; CI 1.65-2.75), and auxiliary facilities workers (RR = 5.26; CI 3.17-8.21). Occupational diseases found in workers of all major specialties, reduced the duration of their active working life almost by 10 years. The conclusion is made about the need for an integrated approach to solve the problem of preservation of carbonyl production worker′s health which includes better working conditions, improved personal protective equipment from the effects of harmful factors, development of medical methods for early diagnosis and prevention of health disorders in this group of workers.