Date of Award

May 2018

Degree Type


Degree Name

Doctor of Philosophy



First Advisor

Junhong Chen

Committee Members

Ilya V Avdeev, Benjamin C Church, Deyang Qu, Cheng Sun


2D nanomaterial, lead recycling, nanocarbon, solar cell, sustainability


To meet the rapidly growing demand for energy and reduce the use of dwindling fossil fuels, the efficient utilization of renewable energy is a constant pursuit globally. Because solar cells convert vastly available sunlight into electricity, developing high-performance and low-cost solar cells is a top strategy for future energy supply. Dye-sensitized solar cells (DSSCs) and perovskite solar cells (PSCs) are the most promising choices. In the meantime, highly concentrated sulfuric acids from retired lead-acid batteries become an environmental concern, and lead contamination in drinking water raises concerns in general public. This study addresses both above-mentioned problems by using two-dimensional (2D) nanomaterials and recycled lead for solar cell fabrication.

Firstly, 2D nanomaterials are used to improve the performance of solar cells as a counter electrode in DSSCs and a hole transport material (HTM) in PSCs. MoS2/graphene hybrids are hydrothermally prepared at different temperatures. A phase transition is observed from 150 to 210 °C, and the reaction temperature of 180 °C leads to the best performing 2D nanomaterial hybrids for electrochemical catalysis. Semi-transparent PSCs are explored in smart buildings to simultaneously adapt to indoor lighting conditions and convert part of sunlight into electricity. Furthermore, through crumbling graphene oxide with copper thiocyanate at 650 °C, a new HTM is prepared for PSCs with steady, high performance and a low cost.

Secondly, the recovery of lead contents from waste acid and contaminated water is studied by using nanocarbon materials. The lead removal in acid is evaluated through adsorption, filtration, and capacitive deionization (CDI). The removal rate is limited, but as-obtained lead wastes are then successfully reformed to produce perovskite precursors. A CDI process through sulfur-treated carbon materials is studied to selectively collect lead contaminants in water. Complete lead recovery and reformation for perovskite precursors is explored to obtain PSCs featuring a low cost and an overall positive environmental impact.

This study addresses a full life cycle of solar cell materials to meet sustainable requirements. Taking advantage of outstanding properties of 2D nanomaterials, results from the study will lead to next-generation solar cells featuring enhanced performance, a lower cost, and better environmental sustainability.

Available for download on Friday, May 24, 2019