Chemical synthesis of amino acids from renewable sources is an alternative route to the current processes based on fermentation. Here, we report visible-light-driven amination of biomass-derived α-hydroxyl acids and glucose into amino acids using NH3 at 50 °C. Ultrathin CdS nanosheets are identified as an efficient and stable catalyst, exhibiting an order of magnitude higher activity towards alanine production from lactic acid compared to commercial CdS as well as CdS nanoobjects bearing other morphologies. Its unique catalytic property is attributed mainly to the preferential formation of oxygen-centered radicals to promote α-hydroxyl acids conversion to α-keto acids, and partially to the poor H2 evolution which is an undesired side reaction. Encouragingly, a number of amino acids are prepared using the current protocol, and one-pot photocatalytic conversion of glucose to alanine is also achieved. This work offers an effective catalytic system for amino acid synthesis from biomass feedstocks under mild conditions.

Black phosphorus (BP), an emerging remarkable photocatalytic semiconductor, is arousing strong interests in this field of solar-driven CO2 reduction, but its stability and activity are still facing huge challenges. Here, an ambient-stable and effective 2D/2D heterostructure of BP/bismuth tungstate (Bi2WO6) with oxygen vacancy is innovatively designed for syngas production via photocatalytic CO2 reduction. This work, not only resolves the stability problem of BP nanosheets by anchoring ultrasmall platinum (Pt) nanoparticles (∼2 nm) but also greatly improves the charge transfer efficiency by constructing S-scheme 2D/2D heterostructure with coupled oxygen defects. As a result, the generation rates of carbon monoxide (CO) and hydrogen (H2) remarkably reach 20.5 and 16.8 μmol g–1 h–1, respectively, which are much higher than that of reported BP-based materials, and the accomplished CO/H2 ratios (1:1–2:1) are exactly the most desirable syngas for industrial applications. Thus, this work constructs an efficient and ambient-stable BP-based photocatalyst for syngas production by CO2 reduction at mild conditions.

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