Solar Photothermal Electrodes for Highly Efficient Microbial Energy Harvesting at Low Ambient Temperatures

Abstract

Temperature is an important parameter for the performance of bioelectrochemical systems (BESs). Energy‐intensive bulk water heating has been usually employed to maintain a desired temperature for the BESs. This study concerns a proof‐of‐concept of a light‐to‐heat photothermal electrode for solar heating of a local electroactive biofilm in a BES for efficient microbial energy harvesting at low temperatures as a replacement for bulk water heating approaches. The photothermal electrode was prepared by coating Ti3C2Tx MXene sunlight absorber onto carbon felt. The as‐prepared photothermal electrode could efficiently raise the local temperature of the bioelectrode to approximately 30 °C from low bulk water temperatures (i.e., 10, 15, and 20 °C) under simulated sunlight illumination. As a result, highly efficient microbial energy could be harvested from the low‐temperature BES equipped with a photothermal electrode without bulk water heating. This study represents a new avenue for the design and fabrication of electrodes for temperature‐sensitive electrochemical and biological systems.

Insights into the Photothermal Conversion of 2D MXene Nanomaterials: Synthesis, Mechanism, and Applications

“…[ 66 ] Currently, most MFCs are operated at controlled temperature of ≈30 °C that is optimal for the cell growth of typical exoelectrogens, where an incubator or temperature‐control device are required to heat the water to maintain the temperature. Wang et al [ 67 ] presented a solar photothermal electrode embedded with Ti 3 C 2 MXene for highly efficient microbial energy harvesting at low ambient temperatures without bulk water heating. The light‐to‐heat conversion property of Ti 3 C 2 MXene enabled the temperature of carbon felt (CF)/MXene electrode immersed in cold water to increase from 20.3 to 32.3 °C under 1 Sun irradiation, where a clear high‐temperature zone around the electrode was observed ( Figure a,b).…”

Two-dimensional MXene enabled carbon quantum dots@Ag with enhanced catalytic activity towards the reduction of p-nitrophenol

“…2c), which are the characteristic diffraction peaks of the XRD of CQD@Ag or MXene. 32 It is obvious that diffraction peaks (111), ( 200), (220), and (311) in CQD@Ag/MXene attest the crystal faces of Ag, [39][40][41] indicating the formation of crystalline Ag on the surface of CQDs.…”

“…CQDs and MXene were prepared according to our previous work. 32,33 Briefly, CQDs was prepared by a one-step hydrothermal method (180 °C, 12 h) of cuttlefish ink powder and MXene was produced by HF-etching (60 °C, 24 h) of Ti 3 AlC 2 .…”

Preparation Strategies and Applications of MXene‐Polymer Composites: A Review

“…MXene has been demonstrated to have unique and appealing photothermal properties, [31,33,139] which shows almost complete absorbance for visible and near-infrared light due to the localized surface plasmon resonance effect. [40,54,140] Owing to the good photothermal conversion performances, MXene-polymer composites can be widely used in solar water desalination, [32] solar photothermal electrodes, [141] biomedical applications, [142] smart hydrogels, [143] and light-driven actuators. [144] The MXene-polymer based interfacial solar steam generation systems have been developed to absorb solar energy and heat seawater to form and collect steam at the air/water interface.…”