Microfluidic Schottky-junction photovoltaics with superior efficiency stimulated by plasmonic nanoparticles and streaming potential

Abstract

Microfluidic-photovoltaic energy harvester with superior efficiency coupling the features of Schottky-junction and streaming potential.

Microdroplet photofuel cells to harvest high-density energy and dye degradation

“…In such a scenario, the m-DropFCs with Au NPs showed enhancement due to the higher ionic conductivity, better charge-transfer rates due to the presence of charge mediators, and occurrence of faster chemical kinetics at the electrode interface due to the enhanced plasmonics. 8,45,56 However, the plot also shows that the m-DropFCs with Fuel 3I registered a sustained charge density of about 1.7 mA cm À2 , which was higher than that of Fuel 2I even aer a long period of time. The ratios of J values aer 0 s and 1500 s were $0.3 (Fuel 2I) and $0.5 (Fuel 3I), which indicated the slower degradation of the Au/CdS NP system.…”

“…It may be noted here that for the system containing additional additives in the electrolyte, j oc is the difference between the chemical potential (m) of the electrolyte and the potential of the conduction band of the photo-sensitive electrode (e.g. ZnPC in the present setup), j oc ¼ E C À m. 8,64 The external irradiation might cause intense localized electric eld to develop on Au NPs, which effectively could reduce m to, m 0 ¼ m À qV, where q represents the charge of the particle and V, the potential developed due to the eld around the excited particle. 8,64 Subsequently, an enhancement in j oc could be expected in a m- DropFC loaded with Au NPs under a prolonged light exposure, as shown in plot (b).…”

“…Concisely, the study showcases the versatility of a droplet 8 or digital 57 microfluidic device loaded with the efficacies of nanoscience for efficient energy harvesting from electrochemical and solar resources as well as performing environmental remediation. 55,56,58 …”

“…The inventions of state-of-the-art thermoelectric, triboelectric, piezo-acoustic, electrokinetic, or Marangoni energy harvesters are directed towards this end. [3][4][5][6][7][8][9] Interestingly, the traditional renewable 10 or non-renewable 11 energy-harvesting technologies have also been undergoing a paradigm shi from the regime of macroscopic to the very large scale integration (e.g. VLSI) of micro or nanoscopic prototypes for enhanced efficiency, higher throughput, and escalated power density.…”

“…In a sense, the droplet-based device is found to be an exception to most of the previous attempts, where lm-based approaches were preferred. 5,8 While the usage of the microdroplet architecture helps in gaining advantages from the connement effects due to miniaturization, the photo-activity of the droplet helps in improving the open circuit voltage (j oc ) and current density (J) of the m-DropFC. 16 The photo-activity 44,45 inside m-DropFCs has been facilitated by the localized surface plasmon resonance (LSPR) 45 of the suspended gold nanoparticles (Au NPs) under light sources.…”