Sustainable Production of Molybdenum Carbide (MXene) from Fruit Wastes for Improved Solar Evaporation.

Freshwater production using solar-driven interfacial evaporation is regarded as a green and sustainable strategy. The biggest barrier to practical deployment of solar desalination, however, continues to be the lack of options for renewable materials. Herein, we present a facile two-step carbonization approach that is sustainable for developing innovative two-dimensional (2D) molybdenum carbide (Mo2 C) materials derived from carbonized fruit wastes. The resultant 2D Mo2 C photothermal layer has an efficient water evaporation rate of 1.52 kg m-2 h-1 with a photothermal conversion efficiency of 94 % under one sun irradiation, which is among the best reported values so far. The broad solar absorption band, high specific surface area (555.1 m2 g-1 ) with large micro- and meso porosity, of the Mo2 C photothermal layer are responsible for these outstanding results. The conversion of food wastes into valuable products, in this case MXene, can potentially inspire greener developments of advanced materials for solar water evaporator.

Membranes prepared from graphene-based nanomaterials for water purification: a mini-review.

Graphene-based nanomaterials (GBnMs) are currently regarded as a critical building block for the fabrication of membranes for water purification due to their advantageous properties such as easy surface modification of functional groups, adjustable interlayer pore channels for solvent transportation, robust mechanical properties, and superior photothermal capabilities. By combining graphene derivatives with other emerging materials, heteroatom doping and rational design of a three-dimensional network can enhance water transportation and evaporation rates through channels of GBnM laminates and such layered structures have been applied in various water purification technologies. Herein, this mini-review summarizes recent progress in the synthesis of GBnMs and their applications in water treatment technologies, specifically, nanofiltration (NF) and solar desalination (SD). Finally, personal perspectives on the challenges and future directions of this promising nanomaterial are also provided.