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Nowadays, hierarchically macro-/meso-/microporous 3D carbon materials have been paid more attention due to their imaginative application potential in specific electrochemistry. Here, we report a dual-template strategy using eutectic NaCl/ZnCl2 melt as airtight and swelling agent to obtain 3D mesoporous skeleton structured carbon from renewable lignin. The prepared lignin-derived biocarbon material (LN-3-1) has a high specific surface area (1289 m2 g−1), a large pore volume (2.80 cm3 g−1), and a well-connected and stable structure. LN-3-1 exhibits extremely high activity and stability in acidic medium for oxygen reduction reaction (ORR), superior to Pt/C catalyst and most non noble-metal catalysts reported in recent literatures. The prepared carbon material was used as a cathode catalyst to assemble a H2-O2 single fuel cell, and its excellent catalytic performance has been confirmed with the maximum power density of 779 mW cm−2, which is one of the highest power densities among non-metallic catalysts so far. Density functional theory (DFT) calculations indicate that the synergy of chlorine and nitrogen reconciles the intermediate adsorption energies, leading to an appropriate theoretical ORR onset potential. We develop a cost-effective and highly efficient method to prepare biocarbon catalyst for ORR in proton-exchange membrane fuel cells.

The reduction of CO2 emission is crucial for the mitigation of climate change. A considerable amount of industrial CO2 can be absorbed in the form of carbonates through high-temperature sorption processes. In this regard, the efficient conversion of carbonates to value-added products will provide an economically viable method for the sustainable usage of carbon compounds. Herein, we report a promising solution involving the use of a glycerol and ethanol mixture as a hydrogen donor in the dry reforming process with CaCO3 to produce syngas. A series of metal active components, including Ni, Fe, Co, Cu, Pt, Pd, Ru, and Rh, was used to promote this reaction. Ni showed comparable performance with that of Pd, but outperformed Co, Fe, Cu, Rh, Ru, and Pt. Approximately 100% conversion of glycerol and ethanol, ∼92% selectivity of synthesis gas (H2 and CO), and a H2/CO ratio of ∼1.2 were achieved over CaCO3 containing 10 wt% Ni (10Ni–CaCO3). Meanwhile, the CO2 concentration was less than 5 vol%, indicating that most of the CO2 captured by the carbonate can be transformed into chemicals; however, they cannot simply be emitted. The CO2 released from the decomposition of CaCO3 not only adjusted the ratio of H2 to CO but also eliminated cokes to guarantee the CO2 absorption–conversion cyclic stability in the absence of steam and at high temperatures.