Correct

睡眠 vs 睡觉

/ shuìmián vs shuìjiào /
Strokes

Definition

睡眠 is a Noun, and 睡觉 is a Verb-object phrase, which means [sleep].

Example

睡眠 is a Noun and is more literary; 睡觉 is a Verb-object phrase that is very colloquial.
1) In examples ① ② 睡眠 is used; if 睡觉 is used instead in example ②, it is no longer a noun but a phrase;

2) In examples ③ and ④, only 睡觉 can be used, not 睡眠.
1
Rén
měitiān
每天
yīnggāi
应该
bǎozhèng
保证
xiǎoshí
小时
de
chōng
充足
shuìmián
睡眠
  

Everyone should sleep at least eight hours a day.

2
Chī
hóngzǎo
红枣
yǒu
有利于
shuìmián
睡眠
  

Red dates are good to your sleep.

3
zuìjìn
最近
shuìjiào
睡觉
zǒng
shuì
不大
hǎo
  

He has been unable to have a good sleep recently.

4
Zuótiān
昨天
lèi
le
  
,
li
夜里
shuì
le
jiào
  
,
jīntiān
今天
de
jiào
比较
wǎn
  

I got up late today for I had a long sleep due to yesterday's weariness.

Related

睡眠睡觉