Alan G. MacDiarmid NanoTech Institute, University of Texas at Dallas, Richardson, Texas 75083, USA.
Nano Lett. 2010 Mar 10;10(3):838-46. doi: 10.1021/nl903267n.
Low efficiencies and costly electrode materials have limited harvesting of thermal energy as electrical energy using thermo-electrochemical cells (or "thermocells"). We demonstrate thermocells, in practical configurations (from coin cells to cells that can be wrapped around exhaust pipes), that harvest low-grade thermal energy using relatively inexpensive carbon multiwalled nanotube (MWNT) electrodes. These electrodes provide high electrochemically accessible surface areas and fast redox-mediated electron transfer, which significantly enhances thermocell current generation capacity and overall efficiency. Thermocell efficiency is further improved by directly synthesizing MWNTs as vertical forests that reduce electrical and thermal resistance at electrode/substrate junctions. The efficiency of thermocells with MWNT electrodes is shown to be as high as 1.4% of Carnot efficiency, which is 3-fold higher than for previously demonstrated thermocells. With the cost of MWNTs decreasing, MWNT-based thermocells may become commercially viable for harvesting low-grade thermal energy.
低效率和昂贵的电极材料限制了利用热电化学电池（或“热电池”）将热能转化为电能。我们展示了实用配置（从硬币电池到可以缠绕在排气管上的电池）的热电池，这些热电池使用相对廉价的碳多壁纳米管（MWNT）电极来收集低品位热能。这些电极提供了高电化学可及表面积和快速氧化还原介导的电子转移，这显著提高了热电池电流产生能力和整体效率。通过直接将 MWNTs 合成为垂直森林，减少了电极/基底连接处的电阻和热阻，进一步提高了热电池的效率。MWNT 电极的热电池效率高达卡诺效率的 1.4%，比以前展示的热电池高出 3 倍。随着 MWNTs 成本的降低，基于 MWNTs 的热电池可能在商业上可行，用于收集低品位热能。
