The imprudent use of fossil fuels has resulted in high greenhouse gas (GHG) emissions, leading to climate change and global warming. Reduction in GHG emissions and energy insecurity imposed by the depleting fossil fuel reserves led to the search for alternative sustainable fuels. Hydrogen is a potential alternative energy carrier and is of particular interest because hydrogen combustion releases only water. Hydrogen is also an important industrial feedstock. As an alternative energy carrier, hydrogen can be used in fuel cells for power generation. Current hydrogen production mainly relies on fossil fuels and is usually energy and CO₂‐emission intensive, thus the use of fossil fuel‐derived hydrogen as a carbon‐free fuel source is fallacious. Biohydrogen production can be achieved via microbial methods, and the use of microalgae for hydrogen production is outstanding due to the carbon mitigating effects and the utilization of solar energy as an energy source by microalgae. This review provides comprehensive information on the mechanisms of hydrogen production by microalgae and the enzymes involved. The major challenges in the commercialization of microalgae‐based photobiological hydrogen production are critically analyzed and future research perspectives are discussed. Life cycle analysis and economic assessment of hydrogen production by microalgae are also presented.

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微藻生产生物氢的主要瓶颈和未来研究的前景

化石燃料的不当使用导致了高温室气体（GHG）排放，从而导致了气候变化和全球变暖。化石燃料储备的减少导致温室气体排放量的减少和能源不安全，导致人们寻求替代性可持续燃料。氢是潜在的替代能源载体，并且特别受关注，因为氢燃烧仅释放水。氢也是重要的工业原料。作为替代的能量载体，氢可用于燃料电池中以进行发电。当前的氢气生产主要依靠化石燃料，并且通常是能源和CO ₂由于排放量大，因此使用化石燃料衍生的氢作为无碳燃料来源是错误的。可以通过微生物方法实现生物氢的生产，由于碳的缓和作用以及利用太阳能作为微藻类的能源，因此将微藻类用于制氢非常出色。这篇综述提供了有关微藻和相关酶产生氢的机理的全面信息。对基于微藻的光生物制氢的商业化过程中的主要挑战进行了严格分析，并讨论了未来的研究前景。还介绍了微藻对氢气生产的生命周期分析和经济评估。