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Surface-capping agents—for example, amphiphilic surfactant molecules, water-soluble polymers, or polyelectrolytes—play a critical role during polymerization reactions for both the formation and stability of colloidal polymer particles. 

CO2 captured species with aqueous metal phosphates are converted to methane in an integrated hydrogenation process over a heterogeneous catalyst. 

Generating a sustainable fuel from sunlight plays an important role in meeting the energy demands of the modern age. Herein we report two-coordinate carbene-metal-amide (cMa, M = Cu(I) and Au(I)) complexes can be used as sensitizers to promote the light driven reduction of water to hydrogen. The cMa complexes studied here absorb visible photons (vis > 103 M-1cm-1), maintain long excited state lifetimes (~ 0.2-1 s) and perform stable photo-induced charge transfer to a target substrate with high photoreducing potential (E+/* up to 2.33 V vs. Fc+/0 based on a Rehm-Weller analysis). We pair these coinage metal complexes with a cobalt-glyoxime electrocatalyst to photocatalytically generate hydrogen and compare the performance of the copper- and gold-based cMa complexes. We also find that these two-coordinate complexes presented can perform photo-driven hydrogen production from water without the addition of the cobalt-glyoxime electrocatalyst. In this “catalyst free” system the cMa sensitizer partially decomposes to give metal nanoparticles that catalyze water reduction. This work identifies two-coordinate coinage metal complexes as promising abundant metal, solar fuels photosensitizers that offer exceptional tunability and photoredox properties. 

Abstract Cellulose is one of the main components of plant matter, which makes it a viable target for biomass conversion to fuels. The direct conversion of cellulose to methane utilizing nickel‐based catalysts often has challenges associated with it. Carbon agglomeration creating nickel‐carbon nanoparticles deactivating catalytic hydrogenation of cellulose has been well reported. Utilizing rare‐earth metals as promoters increases the conversion of cellulose to methane, albeit with deactivation of the catalyst in the form of nickel‐rare‐earth‐carbon nanoparticles. Adding an additional zinc metal promoter eliminates the carbon agglomeration and allows for increased methane yields. Herein, we report an 81 % methane yield from cellulose in 48 hours utilizing a Ni/Zn/Y/Al₂O₃catalyst at 225 °C and under 50 bar H₂pressure.