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The electrochemical CO2 reduction reaction (CO2RR) to produce CO and H2 (syngas) is a promising method for clean energy, but challenges remain, such as controlling the CO/H2 ratios required for the syngas yield. Herein, hydrophobic exfoliated MoS2 (H‐E‐MoS2) nanosheets are fabricated from bulk MoS2 by a cost‐effective ball‐milling method, followed by decoration with fluorosilane (FAS). H‐E‐MoS2 is a cost‐effective electrocatalyst capable of directly reducing CO2 and H2O for tuneable syngas production with a wide range of CO/H2 ratios (from 1:2 to 4:1). In addition, H‐E‐MoS2 shows a high current density, 61 mA cm−2 at −1.1 V, and the highest CO FE of 81.2% at −0.9 V, which are higher than those of unmodified MoS2. According to density functional theory calculations, FAS decoration on the surface of MoS2 electrode can change the electronic properties of the edge Mo atom, which facilitates the rate‐limiting CO‐desorption step, thus promoting CO2RR. Moreover, the hydrophobic surface of H‐E‐MoS2 depressed the H2 evolution reaction and created abundant three‐phase contact points that provided sufficient CO2. The hydrophobization of the electrode may provide an effective strategy for easily tuning the CO/H2 ratio of syngas in a large range for the direct electroreduction CO2 to syngas with an optimized CO/H2 ratio.

3D macroporous hierarchical Ag-G-NCF can efficiently convert CO2 to ethanol with a low overpotential, high faradaic efficiency and high selectivity.

and poly(3,4-ethylenedioxythiophene) (PEDOT). The highly conjugated polymer chains can be reversibly assigned electrochemical properties by a doping/dedoping process. [9][10][11] By regulating and controlling the level of doping, their conductivities can be tuned in a wide range, from 10 −10 to 10 4 S cm, spanning the entire range from insulators to semiconductors, to conductors. [12,13] Additionally, these conducting polymers retain the advantages of traditional polymers, such as low cost, convenient preparation, good affinity to many other materials, and high flexibility and durability. Recently, great efforts have been made to exploit the applications of conducting polymers as electrocatalysts for fuel cells and as electrode materials for supercapacitors. Considering the rapidly booming efforts undertaken in this cutting-edge research area, it is necessary to highlight the new discoveries and achievements in the past several years. Here, we introduce the latest advances in conducting-polymer-based materials for fuel cells and supercapacitors, and focus on the strategies employed to improve their electrocatalytic and electrochemical performance. Conducting-Polymer-Based Catalysts for Fuel CellsFuel cells are promising green energy-conversion devices that convert chemical energy of various fuels directly into electric energy under electrochemical redox reactions. This technology provides intriguing applications in portable energy sources [14,15] and has attracted increasing attention in recent years. [16][17][18][19] Such energy-conversion systems require highly efficient electrocatalysts to trigger the oxygen reduction reaction (ORR) that occurs at the fuel cell's cathode. Platinum/ carbon (Pt/C) composite is demonstrated to be the most efficient catalyst used for fuel cells. [20][21][22] However, high price, scarcity, poor utilization efficiency, and easy carbon monoxide poisoning greatly limit its commercial applications. [23] Therefore, development of low-cost, stable, and efficient electrocatalysts for ORR is a major challenge in the field of fuel cells. [24][25][26][27][28] Owing to their highly tunable conductivity, good electrocatalytic activity, and satisfactory electrochemical stability, conducting polymers are considered to be promising electrocatalyst materials for the ORR. [29] Initially, conducting-polymer-based electrodes were fabricated through direct casting of neutral To alleviate the current energy crisis and environmental pollution, sustainable and ecofriendly energy conversion and storage systems are urgently needed. Due to their high conductivity, promising catalytic activity, and excellent electrochemical properties, conducting polymers have been attracting intense attention for use in electrochemical energy conversion and storage. Here, the latest advances regarding the utilization of conducting polymers for fuel cells and supercapacitors are introduced. The strategies employed to improve the electrocatalytic and electrochemical performances of conducting-polymerbased materials are prese...

The electrochemical CO2 reduction to desired chemical feedstocks is of importance, yet it is still challenging to obtain high production selectivity with low overpotential at a current density surpassing the industry benchmark of 100 mA cm−2. Herein, we constructed a low‐cost Zn single‐atom anchored on curved N‐doped carbon nanofibers (Zn SAs/N−C) by a facile noncovalent self‐assembly approach. At a low overpotential of only 330 mV, the Zn SAs/N−C exhibited simultaneously both a high current density up to 121.5 mA cm−2 and a CO FE of 94.7 %, superior to the previous reports. Experiments and DFT calculations revealed that the Zn atoms in Zn−N4 acted as the active sites, while adjacent pyridine‐N coupled with Zn−N4 could synergistically decrease the free energy barrier for intermediate *COOH formation. Importantly, the curvature of catalyst induced Zn 3d electrons that were bound to the Zn−N bonds to return to Zn atom, thereby leading to an increase in electron density of Zn and accelerating CO2 electroreduction to CO.