Water Splitting–Biosynthetic Hybrid System for CO₂ Conversion using Nickel Nanoparticles Embedded in N‐Doped Carbon Nanotubes

Abstract

CO reduction has drawn increasing attention owing to the concern of global warming. Water splitting-biosynthetic hybrid systems are novel and efficient approaches for CO conversion. Intimate coupling of electrocatalysts and biosynthesis requires the catalysts possess both high catalytic performance and excellent biocompatibility, which is a bottleneck of developing such catalysts. Here, a complex of Ni nanoparticles embedded in N-doped carbon nanotubes (Ni@N-C) is synthesized as a hydrogen evolution reaction electrocatalyst and is coupled with a hydrogen oxidizing autotroph, Cupriavidus necator H16, to convert CO to poly-β-hydroxybutyrate. In Ni@N-C, the Ni nanoparticles are encapsulated in N-C nanotubes, which prevents bacteria from direct contact with Ni and inhibits Ni leaching. As a result, Ni@N-C exhibits excellent biocompatibility and stability. This work demonstrates that electrocatalysts and biosynthesis can be intimately coupled through rational catalyst design.

Tailor-made metal-nitrogen-carbon bifunctional electrocatalysts for rechargeable Zn-air batteries via controllable MOF units

“…For the other Ni based catalysts, the XPS spectra of the Ni 2p (Figure S18a) all exhibit two main peaks at 853.3 ± 0.3 eV and 870.5 ± 0.3 eV without any obvious satellites, corresponding to the metallic dominant structure. Two weak peaks are assigned to NiN x (855.3 ± 0.3 eV) and NiO (856.8 ± 0.3 eV, oxidized in the air),respectively [77][78][79][80]. The similar results for Co based catalysts with different locations of peaks (for Co 0 , CoN x and CoO)16,[81][82][83] are shown in (Figure S18b), which indicates Co 0 as the dominant chemical states of Co.…”

Ultrathin tin monosulfide nanosheets with the exposed (001) plane for efficient electrocatalytic conversion of CO2 into formate

“…The electrochemical CO 2 reduction reaction (CO 2 RR) has been recognized as a promising strategy to convert problematic CO 2 into value-added feedstocks, thanks to the multiple advantages of the electrochemical route, including mild conditions (i.e., ambient pressure and room temperature), potential synergy with renewable energy, and product tunability. [1][2][3][4][5][6][7] However, the electrochemical CO 2 RR occurs at a potential close to that of the hydrogen evolution reaction (HER), inevitably leading to a rather low selectivity toward the CO 2 RR since the HER is thermodynamically more favorable in most electrocatalysts. Moreover, the development of advanced CO 2 RR electrocatalysts still faces issues of high overpotential, low efficiency, slow kinetics, and poor stability.…”

Enhancing Biosynthesis and Manipulating Flux in Whole Cells with Abiotic Catalysis

“…The development of new electrode materials provides another way of mitigating ROS toxicity. Wang and colleagues developed a polyoxometalate (POM) water splitting system that showed negligible production of hydrogen peroxide during water splitting, [30] while separate work showed that embedding nickel nanoparticles in n‐doped carbon nanotubes minimized Ni 2+ leaching and ROS generation [31] . A ROS‐resistant cobalt phosphorous (Co−P) alloy cathode combined with a self‐healing CoPi anode that scavenges leached cobalt ions simultaneously provides a solution to the problems of ROS generation and electrode leaching [32] .…”