Molecular Solar Thermal Power Generation

Abstract

Harvesting solar energy into electrical power can be an attractive way for the development of cleaner energy. However, traditional solar photovoltaic technologies operate strongly dependent on solar intermittency. Molecular solar thermal energy storage (MOST) is a new technology based on photoswitchable materials, which allow sunlight to be stored and released as chemical energy on-demand. We here characterized the photophysical properties of two MOST couples both in liquid and phase interconvertible neat film. Their suitable MOST properties let us combine them individually with a microelectromechanical ultrathin thermoelectric chip to use the stored solar energy for electrical power generation. The generator can produce a surface output power up to 1.2 mW·m<sup>-2</sup> for the liquid form and 0.6 mW·m<sup>-2</sup> for the neat film form. Our results demonstrated that such a molecular thermal power generation system has a high potential to store and transfer solar power into electricity, and is thus independent of geographical restrictions.

Storing energy with molecular photoisomers

“…Several NBD systems with push-pull substituents allow a higher number of cycles in solution (maximum degradation rate of 0.14% per cycle). [124][125][126] In addition, embedded oligo (phenylene ethynylene) arms end-capped with thioacetate groups NBD show excellent reversibility of up to 99.9995% in toluene. 127 However, neat samples degrade after just a few cycles.…”

“…Such integrated devices were able to continuously generate power densities of up to 1.3 W m À3 , showing that, on a small scale, opportunities exist for local solar energy storage and power production beyond traditional photovoltaic-electrochemical cell technologies. 126 The heat gradients achievable in current MOST systems are insufficient to drive a traditional heat engine system; however, the novel development of a MEMS-TEG chip has demonstrated the feasibility of continuously generating electrical power from these systems. We note that this concept has generated a new type of solar cell that is independent of time and geographical restrictions and dramatically extends the application range of MOST systems.…”

“…The heat released by the MOST solution is captured by a TEG chip for electric power generation 126 ;(D) Power generation using neat form of MOST-TEG. Charged neat form MOST material is coated on top of the TEG chip and a laser trigger is used to release heat for further power generation 126.…”

A Norbornadiene-Based Molecular System for the Storage of Solar–Thermal Energy in an Aqueous Solution: Study of the Heat-Release Process Triggered by a Co(II)-Complex

“…Yet, the insertion of substituents (especially bulky ones) can have deleterious effects on the energy storage density, as a consequence of increasing the molar mass of the MOST, and may not favor quantum yield [4]. Nevertheless, successful NBD/QC systems have been engineered and some test devices for solar energy capture and heat release have opened great expectations for future applications [21][22][23][24][25]. A schematic representation of a MOST-based plant for domestic use is shown in Figure 1b.…”