Weiting Yu,Zhe Yang,Rendan Zhu,Mengzhi Lu,Tingjiang Lu,Yan Yu,Shuang Song
The photo-assisted electrochemical CO 2 reduction reaction (CO 2 RR) toward CO stands as a highly promising pathway for addressing environmental challenges and produces valuable chemicals. In this study, a novel pl-Si/Ag/Pc electrode was developed with the surface enveloped by an amorphous phthalocyanine overlayer. The pl-Si/Ag/Pc electrode has gained recognition as a catalyst of exceptional quality, displaying superior activity, selectivity toward CO, and stability. A synergistic mechanism has been revealed from experimental results that Ag served as active centers for CO 2 RR, Pc facilitated CO 2 adsorption and suppressed the competing HER reaction. Functionalizing the surface of electrode with Pc enhanced the CO selectivity (FE CO at 90.8 % under −1.5 V vs RHE) during the CO 2 RR process and reduced the cost in following product separation procedures. This study presents an uncomplicated yet effective approach for formulating durable and discerning electrocatalysts dedicated to the utilization of CO 2 .
Aqueous lithium-ion batteries (ALIBs) are attracting intense attention because of the intrinsic nonflammable nature of the aqueous electrolytes. However, its own narrow electrochemical window has led to numerous problems such as dissolution of electrode materials, hydrogen evolution at the anode, and poor cycling stability. Here, we report an “overcrowded electrolyte” using 1,4-dioxane as an additive, which has lone pairs of electrons on the oxygen atom to disrupt the original water-hydrogen bonding network by forming intermolecular hydrogen bonds, thereby inhibiting the hydrogen evolution reaction (HER) and decreasing the water activity. Furthermore, a layer of crystalline Li2CO3 is coated onto the surface of the TiNb2O7 anode material by supercritical fluid CO2 technology. The dense hydrophobic Li2CO3 coating layer can serve as a physical protection, which effectively blocks the direct contact between electrolyte and electrode. Under the synergistic effect of those two aspects, HER is greatly suppressed and the interface stability is enhanced. As a result, LiMn2O4/TiNb2O7 full cells exhibit a high initial coulomb efficiency of 95% with a capacity retention rate of 92% over 500 cycles under 1 C rate. This work provides a fundamental understanding of the interfacial chemistry of ALIBs and makes an important step forward in the development of high-performance and low-cost ALIBs for practical applications.
Lei Shi,Shuping Zhang,Liren Yang,Yinhai Su,Yuanquan Xiong
As a more reliable form of energy storage than lead-acid battery, lead–carbon battery plays a key role in the field of electric vehicles and energy storage systems, but it still faces some problems in the application process. To prolong the cycle life of lead–carbon batteries under high rate partial state of charge (HRPSoC) duty and focus on solving the problem of hydrogen evolution reaction (HER) of batteries, a facile strategy using phosphoric acid as activator for preparing P-doped biomass-derived mesoporous carbon was proposed. Compared with commercial activated carbon (AC) and carbon material obtained under other preparation conditions, the P-RHMC-2 using material ratio with 1:2 as well as activated at 550 ℃ has the highest mesoporous rate and excellent P-doping effect. In the electrochemical test, P-RHMC-2 inhibits HER dramatically and improves the cycle life of lead–carbon battery significantly under HRPSoC duty when it applied to the negative electrode of the batteries.