甲醇燃料电池的催化性能比较外文翻译资料-毕设翻译网

英文原文：

Fuel Cells and Their Prospects

A fuel cell is an electrochemical conversion device. It produces electricity from fuel (on the anode side) and an oxidant (on the cathode side), which react in the presence of an electrolyte. The reactants flow into the cell, and the reaction products flow out of it, while the electrolyte remains within it. Fuel cells can operate virtually continuously as long as the necessary flows are maintained.

Fuel cells are different from electrochemical cell batteries in that they consume reactant from an external source, which must be replenished--a thermodynamically open system. By contrast batteries store electrical energy chemically and hence represent a thermodynamically closed system.

Many combinations of fuel and oxidant are possible. A hydrogen cell uses hydrogen as fuel and oxygen (usually from air) as oxidant. Other fuels include hydrocarbons and alcohols. Other oxidants include chlorine and chlorine dioxide.

Fuel cell design

A fuel cell works by catalysis, separating the component electrons and protons of the reactant fuel, and forcing the electrons to travel though a circuit, hence converting them to electrical power. The catalyst typically comprises a platinum group metal or alloy. Another catalytic process takes the electrons back in, combining them with the protons and oxidant to form waste products (typically simple compounds like water and carbon dioxide).

A typical fuel cell produces a voltage from 0.6 V to 0.7 V at full rated load. Voltage decreases as current increases, due to several factors:

Activation loss
Ohmic loss (voltage drop due to resistance of the cell components and interconnects)
Mass transport loss (depletion of reactants at catalyst sites under high loads, causing rapid loss of voltage)

To deliver the desired amount of energy, the fuel cells can be combined in series and parallel circuits, where series yield higher voltage, and parallel allows a stronger current to be drawn. Such a design is called a fuel cell stack. Further, the cell surface area can be increased, to allow stronger current from each cell.

Proton exchange fuel cells

In the archetypal hydrogen–oxygen proton exchange membrane fuel cell (PEMFC) design, a proton-conducting polymer membrane, (the electrolyte), separates the anode and cathode sides. This was called a 'solid polymer electrolyte fuel cell' (SPEFC) in the early 1970s, before the proton exchange mechanism was well-understood. (Notice that 'polymer electrolyte membrane' and 'proton exchange mechanism' result in the same acronym.)

On the anode side, hydrogen diffuses to the anode catalyst where it later dissociates into protons and electrons. These protons often react with oxidants causing them to become what is commonly referred to as multi-facilitated proton membranes (MFPM). The protons are conducted through the membrane to the cathode, but the electrons are forced to travel in an external circuit (supplying power) because the membrane is electrically insulating. On the cathode catalyst, oxygen molecules react with the electrons (which have traveled through the external circuit) and protons to form water — in this example, the only waste product, either 参考译文：

燃料电池是一种电化学转换装置。它产生的电流来自于燃料（阳极侧）和氧化剂（阴极侧）在电解液作用下的化学反应。反应物（燃料）源源不断地流入电池，而反应产品（也就是电能）则从电池中流出，同时电解液依然保留在电池内部。只要保持必要的燃料供给,燃料电池几乎可以持续不断地产生电能。

有许多种燃料和氧化剂的组合都是可行的。氢燃料电池使用氢作为燃料，而用氧气（通常来自于空气）作为氧化剂。其它燃料包括碳氢化合物和醇类。其它氧化剂包括氯和二氧化氯。

燃料电池是通过催化作用进行工作的，催化剂通常包括铂族金属或合金。在催化作用下将反应燃料的组成部分电子和质子分离，并迫使电子沿回路移动，从而将其转化为电流。另一种催化过程需要将电子与质子和氧化剂相结合，形成废物产品（通常是简单的化合物，像水和二氧化碳）。

（催化剂）活性的损失