Direct carbon solid oxide fuel cells powered by rice husk biochar

Abstract

The inefficient application of fossil energy is one of the fundamental factors leading to global warming. Bioenergy is a renewable energy and also a carbonneutral energy, with advantages of extensive sources, diverse products, and environmental friendliness. Direct carbon solid oxide fuel cell (DC-SOFC) is a novel high-efficient bioenergy technology, which is able to directly convert the chemical energy of biochar into power. A biochar derived from rice husk is applied to power an electrolyte-supported DC-SOFC. The maximum power density of the cell with pure rice husk biochar is 135 mW cm À2 at 850 C, which enhances to 214 mW cm À2 after using a Boudouard reaction catalyst.The microstructures, components and thermochemical parameters of the biochar are characterized and analyzed. The results show that the microstructure of the rice husk biochar is rough and porous. Na, K, Mg, Al, and other elements are found to present in the biochar. The physicochemical properties of the biochar and the enhanced electrical output of the DC-SOFCs are demonstrated and discussed in detail. K E Y W O R D S biochar, Boudouard reaction, direct carbon fuel cell, Fe catalyst, rice husk 1 | INTRODUCTION Climate change characterized by global warming is one of the most significant environmental and development challenges that human society has faced since the Second World War. 1 On September 22, 2020, President Xi Jinping announced that China would strive to reach the peak of carbon dioxide emissions by 2030 and achieve carbon neutrality by 2060. This goal is challenging for China. The realization of carbon neutrality requires large-scale emission reductions in the energy, industry, construction and transportation sectors. Biomass energy is a special

Biochar from Lignocellulosic Biomass: The Importance of Physicochemical Characterization and Multi-Criteria Decision Analysis for Its Applications

“…Some applications for biochar as solid fuel are shown in Table 5, where it is possible to identify the correlation between biochar preparation conditions and HHV. In other fuels-related applications, biochar as an electrode has been studied in the composition of solid oxide fuel cells with exciting results [124,125]. One such is using the composition of anodes for lithium-ion batteries, where extensive surface area, porosity and ion storage capabilities are desired [126].…”

Carbon derived from treated rice husk as fuel for direct carbon fuel cells

“…11 Recently, RH carbon (RHC) has been used in DCFCs, and the performance has been further improved from 135 to 214 mW cm À2 at 800 C by loading the catalyst of Fe ions to catalyze the Boudouard reaction. 12 RH comprises mainly carbon skeleton with cellulose, hemicellulose, and lignin. Besides the main carbon component, RH contains 18 AE 2 wt% ash content, a few metal ions, and 90% silicon accounting.…”

“…It is also suggested in a recent report that using RH to produce one megajoule of energy has dramatically reduced the impact of global warming, which is only one‐34th of using coal 11 . Recently, RH carbon (RHC) has been used in DCFCs, and the performance has been further improved from 135 to 214 mW cm −2 at 800°C by loading the catalyst of Fe ions to catalyze the Boudouard reaction 12 . RH comprises mainly carbon skeleton with cellulose, hemicellulose, and lignin.…”